1. Frogs are tailless amphibians. Amphibians are cold-blooded vertebrate animals. They differ from reptiles in that they lack scales and most return to water to breed. The frog belongs to the family Ranidae which contains more than 400 species.
2. Frogs can be found on every continent except Antarctica. Members of the frog family include the bullfrog, common frog, green frog, leopard frog, marsh frog, pickerel frog, and wood frog. Toads can be found everywhere except Australia, polar regions, Madagascar and Polynesia.
3. All toads are actually frogs. There are more than 300 species of toads. These types of frogs (toads) have stubby bodies with short hind legs for walking instead of hopping. They have warty and dry skin, usually preferring dryer climates. They also have poison glands behind their eyes.
4. Some records show that in captivity, many species of frogs and toads can live for between 4 to 15 years. The longest lifespan recorded was a European Common Toad. One lived to be 40 years old.
5. Frogs have two bulging eyes. They also have strong, long, webbed hind feet that are adapted for leaping and swimming. Frogs can hear using big round ears on the sides of their head called a tympanum. Male frogs make sounds by squeezing their lungs with their nostrils and mouth shut. Air flows over their vocal chords and into their vocal sacs blowing it up like a bubble gum balloon. Some frogs have tongues that are long and sticky that can be used to catch bugs. Most frogs have a ridge of very small cone teeth around the upper edge of the jaw. They don't have anything that could be called teeth on their lower jaw, so they usually swallow their food whole. The so-called "teeth" are mainly used to hold the prey and keep it in place till they can get a good grip on it and squash their eyeballs down to swallow their meal. Toads, however, do not have any teeth.
6. Frogs have very special skin. It not only covers their bodies but they drink and breathe through it.
7. Frogs get oxygen through their skin when it's moist, so they need to take care of their skin or they might suffocate. Sometimes you'll find frogs that are slimy. This is because the frog’s skin secretes a mucus that helps keep it moist. Even with the slimy skin, these frogs need to stay near water. Toads on the other hand have tougher skin that doesn't dry out as fast, so they can live farther from water than most frogs. Frogs shed their skin regularly to keep it healthy. Some frogs shed their skin weekly, others as often as every day.
8. Frogs tend to lay eggs in clusters and lay many eggs because there are many hazards between fertilization and adulthood. The life cycle of the frog has many stages. The frog starts out as an egg. It hatches and becomes a tadpole. At about nine weeks of life, tiny legs start to sprout, the head becomes more apparent and the body gets longer. The arms will begin to bulge where they will eventually pop out, elbow first. The tadpole now looks more like a teeny frog with a really long tail. By between 12 to 16 weeks, depending on water and food supply, the frog has completed the full growth cycle.
9. The biggest kind of frog is the Goliath frog. They come from Cameroon in West Africa. Their bodies can reach the size of nearly a foot (30 cm) long, and their legs are that long also. The Goliath frog can weigh as much as a large housecat. The smallest frog in the Southern Hemisphere is the Gold Frog. Gold Frogs can measure only 3/8 of an inch (1 centimeter).
10. Frogs have to watch out for all kinds of enemies in the wild. There are a wide variety of frog predators. Animals that eat frogs include snakes, lizards, birds, and various small animals like hedgehogs. Even under water frogs can’t be safe from some fish, swimming mammals, and even diving birds! Frogs even have to watch out for other hungry frogs. Frogs in the environment are a true sign of a well balanced ecosystem. The biggest enemy of the frog is pollution.