General Frog Facts
You might think that something that looks like a frog with strong hind legs, webbed feet, round bulging eyes and smooth, thin green skin with spots or a lizard-like pattern would not be endearing. However, scientists love this species—all 3,500 different kinds—because they are special.
Female frogs lay eggs in water, such as ponds or streams, and males come by to fertilize the stash. Out hatch tadpoles, who live a life of swimming until their legs develop, their tails drop off and they become small frogs. Surviving polliwogs then hop onto land and eat invertebrates. They become part of several food chains.
Frogs are amphibians, adaptable to both water and land. Similar to humans, they are vertebrates, meaning they have a spine. Their limbs are modeled like ours too, with a long bone and two lower bones that attach at wrist, ankle, hand and foot.
They also have smooth skin that soaks up air, sun and the water around them. That makes them a kind of barometer for their surroundings. They are a gauge of their environment.