Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.

Older Male Sparrows Not Threatened by Younger Males

Older male white-crowned sparrows don't see younger male sparrows as much of a threat. When vying for mates or squabbling over territory, older males don't often bother challenging their younger rivals because they pose little credible competition. Instead, they only pick a fight with other older males that could pose a significant threat to their superiority.

It turns out, the way these birds figure out each others' seniority is based on their songs as well as their plumage. Male white-crowned sparrows use song for multiple purposes including attracting a mate and claiming their territory. Since young male white-crowned sparrows sing differently than older males, song can be used to distinguish age.

After mapping the territories of 16 male white-crowned sparrows, the research team was able to observe how males of different ages responded to songs made by intruders.

They found that older birds did nto react as strongly when they heard the song of a younger bird in their territory.

Photo © Douglas Nelson / Ohio State University

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Communities and Ecosystems

Nature is a mosaic of complex interactions and relationships between animals, plants, and their environment. Individual organisms belong to populations, species, communities, and ecosystems. Energy flows from one organism to another and it is through these relationships that populations influence each other and the environment. Find out more about community and ecosystems.

Falcons

Falcons are a group of birds of prey that includes 37 species. Falcons fall into several general groups including the kestrels, the hobbies and their relatives, the peregrine falcon and its relatives and the hierofalcons. The fossil record for falcons is not as complete as other birds of prey.

European Badgers

The European badger is a mammal native to Europe noted for the extensive tunnels it builds. These tunnels, also known as sets or dens, are as much as six feet deep and can measure some 1000 feet in length with many chambers and openings that create a complex underground network.

Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.

The Movement Patterns of Leatherback Turtles

Leatherback turtles in the Eastern Pacific Ocean spend more energy searching for prey than the leatherback turtles that inhabit the North Atlantic ocean. A team of scientists led by Helen Bailey of the University of Maryland Center for Environmental Science discovered that turtles in the Atlantic traveled at different speeds. When foraging, the Atlantic turtles traveled at low speeds but when in transit from one foraging ground to the next they travelled at higher speeds.

In contrast, leatherback turtles of the Eastern Pacific Ocean travelled at just one speed and spent most of their time searching for good foraging areas. This means that turtles that inhabit the Atlantic may be able to recover from population declines more easily than those that live in the Pacific.

Brittle Stars and Basket Stars Echinoderms with Inflexible Arms

Like sea stars, brittle stars and basket stars have (in most species) five arms (which in some species are highly branched). But the arms of brittle stars and basket stars differ from those of star fish in that their central disk is easily distinguished from their arms (in starfish, the arms blend with the central disk such that it is difficult to see exactly where the two meet).

Brittle stars are so named because their arms can only move side to side and not up and down. If their arm is forced either up or down, it breaks. The lateral arm movements used by brittle stars and basket stars enables them to crawl across the substrate or cling to surfaces. There are about 2000 species of brittle stars and basket stars and they exhibit a range of feeding methods from filter feeding to scavenging to predation.

Large Herbivores Increase Forest Diversity

Rhinoceroses and elephants play a critical role in keeping the tropical forests of Southeast Asia healthy. These large herbivores help to disperse seeds and in doing so bolster forest regeneration and the maintenance of boidiversity.

The forests of Southeast Asia are rich in species number. They are also structurally dense which means dispersal of seeds can be tricky. The tightly packed forest dampens winds so wind dispersal is not often successful. Also, seeds that do make it to the ground often perish in the thick darkness shed by the dense canopy.

The most successful means of seed dispersal in such forests is to rely on seed transport by animals. Animals eat the fruit of the tropical vegetation and seeds are dispersed after the animal wanders away and either regurgitates the seeds or defecates them. Herbivores such as elephants and rhinoceroses not only eat more, they also wander further distances and can eat larger fruits and seeds. This means under normal conditions, these animals play a significant role in seed dispersal.

But habitat loss, poaching and killing of animals due to conflicts with humans, has taken a significant toll on the populations of rhinoceroses and elephants in Southeast Asia. Populations of Asian elephants, Javan rhinoceroses and Sumatran rhinoceroses have suffered dramatic declines and some species are on the brink of extinction. Such declines mean that the diversity and robustness of the very tropical forests in which elephants and rhinoceroses live are in grave danger.

Photo © Dicky Singh / iStockphoto.