What is a bird?
There are more than 10,000 species of birds throughout the world, from the tiny Anna’s hummingbird at 4.07 g to 4.31 g (.143 oz to .152 oz.) to the African ostrich 90 to 130 kilograms (198 to 287 pounds). Birds are endothermic or warm blooded, two-legged, egg-laying vertebrates with feathers and wings – though many species of birds are unable to fly such as emus and penguins. Some birds hatch and are covered in down and able to eat on their own, such as chickens or geese. This is called precocial. Others, such as robins, are altricial, and are hatched without down and must be fed by one or both of the parents.
What is a mammal?
The basic definition of a mammal is a group of animals with backbones, whose bodies are insulated by hair and contain sweat glands, nurse infants with milk from mammary glands and have a unique jaw articulation. However, mammals are remarkably diverse and range from the tiny Kitti’s hog-nosed bat weighing 1.5 grams (.05 oz.) to the blue whale weighing in at up to 136,000 kg (300,000 lbs).
There are more than 4,000 species of mammals across the globe. Their adaptations to their environment are unique and they inhabit every continent and every ocean in the world. Mammals are able to regulate their body temperatures since they are endothermic or “warm blooded” which means they control their body temperatures internally.
What are reptiles and amphibians?
Reptiles are vertebrates with scaly skin to protect their bodies. Their young look like miniature versions of the adults when they hatch. Snakes and lizards are reptiles. Reptiles can only control their body temperature by basking in the sun or finding shady areas to cool down because they are ectotherms or “cold blooded.”
Amphibians live part of their lives in water and part on land. Like reptiles, they are ectothermic. These vertebrates hatch from eggs laid in the water and go through stages of metamorphosis, from egg to larva to adult. Frogs and toads are amphibians.
What are invertebrates?
The majority of life on this planet is made up of invertebrates. Since this group is so huge, it is also very diverse and includes marine animals such as sea cucumbers, corals and lobsters, and spiders, beetles, ants and other insects on land. Insect diversity is an intrinsic part of the Earth's ecosystems. They are what make ecosystems tick, many by converting organic waste into nutrients for the soil which in turns nourishes the plants and trees.
Not currently on exhibit:
* These represent animal species at Woodland Park Zoo, unless noted. Any of these animals may not be on exhibit at any time, without notice.