Frogs

Frogs are found all over the world. They are diverse in size, color, and habitat. Every frog has one thing in common - metamorphosis. They have a unique life cycle which involves changing their appearance, diet, and how they breathe. What makes them different and similar makes them interesting.

There were 2600 known species of frogs and toads in 1985. In 2007 there were 3400. As of February 2012, there are 6112 known species living on every continent except Antartica. Most frogs live in warm, moist environments where they have bodies of water to breed in. Some species have adapted to live in temperate zones or desert biomes. Even in the harshest habitats frogs reproduce in water.

The frog’s life starts when the female lays unfertilized eggs in a pond. The male leave spawn and the eggs are fertilized. The eggs divide and develop into tadpoles with gills and tails. Tadpoles get oxygen from the water and eat algae. After 21 days they start to change.

Tadpoles grow legs and lungs and lose their gills and tails. Their mouths get larger for their transformation to carnivores. The frogs leave pond life for land coming back to eat and breed.

Frogs have many enemies. Predators include snakes, birds and even other frogs! Frogs camoflage themselves using skin colors like green and brown to hide. Some have red or blue skin to warn that they are poisonous. They have eyes on top of their heads so they can see while they swim unseen.

Frogs are endangered by invasive species, pollution, and the chytrid fungus. The fungus has decimated frog populations in warmer climates. Subtropical and tropical species have been hardest hit. Mountain species in cooler climates have been untouched. Scientists are looking for a cure.

Frogs are indicators of ecological health. We must protect them! _