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Rabies

A viral disease that affects the nervous system in mammals. It can lead to paralysis and death. Rabies is spread from the bite of one mammal to another.

Rain forest

A woodland that receives more than 100 inches (250 centimeters) of rain each year. Tropical rain forests are known for warm temperatures, and have evergreen trees that form a dense, continuous canopy. Temperate rain forests have evergreen and deciduous trees, with temperatures that vary greatly with the season.

Range

In biology, the total area in which an individual or species can be found.

Raptor

A bird that hunts and eats meat; also known as <i>bird of prey.</i> Raptors use their talons to catch their food and their strong, curved beaks for tearing food into bite-sized pieces. Falcons, hawks, eagles, and owls are raptors.

Rare

A species that has small populations, so that even a slight decrease in numbers could cause extinction.

Recycle

To reuse an item instead of just throwing it away. For example, soda cans can be recycled to make new soda cans.

Regenerate

Formed or created again.

Regurgitate

To bring up food that is partly digested. Many bird species feed their young with food they have swallowed and then regurgitated. The regurgitated food is easier for the chick to swallow than whole food would be.

Rehabilitate

To care for an animal until it is in good health again and can be released to its natural habitat.

Reintroduce

To release a captive animal back into its native habitat in the wild.

Renewable

Resources that have the capacity to replenish themselves within a human's lifespan.

Repatriate

To send an animal back into the same wild area its ancestors came from.

Reproduce

To have offspring or babies.

Reproductive potential

The ability of an animal to reproduce given ideal conditions, such as good health and a safe environment.

Reptile

A cold-blooded, air-breathing animal that has a backbone. Reptiles have dry, scaly skin. They move by either creeping on short legs or crawling on their bellies. Most reproduce by laying eggs.

Reticulated

This word means <i>looks like a net,</i> and is used to describe the pattern on the skin of some animals. For example, there are reticulated giraffes and reticulated pythons.

Retractable

Cats (except cheetahs) and fossas have the ability to pull in, or retract, their claws when not in use.

Riparian

Community of plants and animals found along waterways.

Rodent

Generally, a small mammal with soft fur. Rodents have large front teeth (incisors) that never stop growing. Rodents are mammals. Guinea pigs, hamsters, mice, rats, and squirrels are all rodents.

Roost

A place where flying birds and bats rest or sleep, or where a bird builds its nest.

Ruminant

Having a multi-chambered stomach. Cows and goats are examples of ruminants.

Runner babies

Animal offspring that stay with their mothers all the time, as opposed to hiding in a secure place while their mothers search for food (see tucker babies). Giraffes and zebras are runner babies.