By natural selection, the nature of the species gradually changes to become adapted to the niche. If a species becomes very well adapted to its environment, and if the environment does not change, species can exist for a very long time before they become extinct. An excellent example of an animal evolving to fill a niche is seen in the evolution of horses. Many fossils of different kinds of horses have been discovered, and paleontologists think that the earliest ancestor of the modern horse lived in North America more than 50 million years ago.
This animal was a small padded-foot forest animal about the size of a dog. If you saw one next to a modern horse, you might not even think the two were related! As time passed, the climate of North America became drier, and the vast forests started to shrink.
Grasses were evolving, and the amount grassland was increasing. Horses adapted to fill this new grassland niche. They grew taller, and their legs and feet became better adapted to sprinting in the open grasslands.
Their eyes also adapted to be further back on their heads to help them to see more of the area around them. Each of these adaptations helped the evolving grassland horses to avoid predators. Their teeth also changed to be better adapted to grinding tough grassland vegetation. Have you ever wondered what purpose the "dew" claw on the inside of a dog's paw serves? The claw is the dog's thumb. Let's explore the different adaptations of plants and animals living in each major land biome. Directions : Click on the plus sign on each image to learn more about the biome shown and the plants and animals that have adapted to survive there.
Directions : Take a look at the physical and behavioral adaptations of three different types of squirrels —the antelope squirrel, the Douglas squirrel, and the Barbary squirrel. Predict which ecosystem each squirrel is best adapted to — the grassland, the desert, or the forest. After you have made your predictions, drag and drop your predictions to the correct ecosystem to check your answers.
Utahcamera , Antelope Squirrel, Wikimedia Commons. Physical Adaptations: Active mostly late at night or early morning, antelope squirrels have adapted the ability to lower their body temperatures to withstand extremely hot environments. Behavioral Adaptations: Antelope squirrels become less active when food is scarce to preserve energy. Physical Adaptations: Active most of the day, Douglas squirrels have adapted sharp claws that make them great climbers.
Behavioral Adaptations: Douglas squirrels collect nuts mid-to-late summer in preparation for the winter. Physical Adaptations: Active mostly in evenings or early mornings, Barbary squirrels have adapted long, bushy tails to blend in to their environment. Behavioral Adaptations: Barbary squirrels generally build their nests or burrows by a water source and usually do not travel far to avoid predators.
After you make your predictions, click to see descriptions of adaptations for each organism and take notes in your journal. Their sooty color blended in with the trees, which were stained by industrial pollution. The cream-colored moths began to make a comeback after the United Kingdom passed laws that limited air pollution. Speciation Sometimes, an adaptation or set of adaptations develops that splits one species into two.
This process is known as speciation. Marsupials in Oceania are an example of adaptive radiation , a type of speciation in which species develop to fill a variety of empty ecological niches. Marsupials, mammals that carry their developing young in pouches after a short pregnancy, arrived in Oceania before the land split from Asia. Koalas Phascolarctos cinereus , for instance, adapted to feed on eucalyptus trees, which are native to Australia.
The extinct Tasmanian tiger Thylacinus cynocephalus was a carnivorous marsupial and adapted to the niche filled by big cats, like tigers, on other continents. Sympatric speciation is the opposite of physical isolation. It happens when species share the same habitat.
Adaptations have allowed hundreds of varieties of cichlids to live in Lake Malawi. Each species of cichlid has a unique , specialized diet : One type of cichlid may eat only insects, another may eat only algae , another may feed only on other fish. Coadaptation Organisms sometimes adapt with and to other organisms. This is called coadaptation. Certain flowers produce nectar to appeal to hummingbirds.
Hummingbirds, in turn, have adapted long, thin beaks to extract the nectar from certain flowers. When a hummingbird goes to feed, it inadvertently picks up pollen from the anthers of the flowers, which is deposited on the stigma of the next flowers it visits. The coadaptation is beneficial to both organisms. Mimicry is another type of coadaptation. In mimicry, one organism has adapted to resemble another. The harmless king snake sometimes called a milk snake has adapted a color pattern that resembles the deadly coral snake.
This mimicry keeps predators away from the king snake. The mimic octopus Thaumoctopus mimicus has behavioral as well as structural adaptations. This species of octopus can copy the look and movements of other animals, such as sea snakes, flatfish, jellyfish, and shrimp. This can lead to co-extinction. In southern England, the large blue butterfly adapted to eat red ants. An adaptation is passed from generation to generation.
Female mammals produce milk to feed their offspring. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.
Stephen M.
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