Nancy Jones, age 11, of San Manuel, Arizona, for her question:
How manv different frogs are there?
If you combed every stream and moist pond in North America, you might find about 22 different frogs. In the whole world, you might find 100 species of true frogs.
This does not include the toads, the tree frogs and true toads or several smaller groups that differ slightly from the genuine frogs. The total number of frogs and fropgy relatives includes around 2,000 different species.
A true frog has teeth, a moist skin and a private pool where he spends much of his time. A true toad has no teeth, a warty skin and often enjoys life in a meadow. The various tree frogs and tree toads have discs on their fingers and toes, which they use to cling and climb through the foliage where they spend most of their time. All these cousins are tailless amphibians, classified in the Order Salientia, which means "the leapers."
The 2,000 or so leapers are so much alike that we tend to regard them all as frogs. But this is not precise enough for the scientists. They subdivide the large group of leapers into smaller families and still smaller genera, each of which is called a genus. All the true frogs belong in the Family Ranidae. About 140 of these ranids have been identified throughout the world, though others may be discovered and added to the list. Our 22 native North American frogs all happen to belong in the family unit called genus Rana.
The scientific names of most animals are coined from older Latin or Greek words, known to scholars of all nationalities. Rana happens to be the Latin word for frog. Spanish is closely related to Latin and the older word for the frog remained unchanged. In Spanish speaking Latin America, he is known as "la rana." However, true frogs are not very common in that part of the world. But the people there tend to confuse them, as we do. The frog and toad relatives look so much alike that the name rana seems to suit all, or most of them.
Bufo is the Latin name for a toad. It was borrowed to name the Family Bufonadae and the genus Bufo. This is the family of the true toads and throughout the world there are about 100 species. About 16 true toads are native Americans. Our various tree toads belong in another family. So do our tree frogs.
Our champion leaper is the leopard frog, who is common everywhere except in the western mountains. He wears handsome speckles and during, the busy season he adds a snoring note to the nightly frog chorus. The preen frog, another member of f the same glee club, adds a note like a banjo. Also in the chorus is the big bullfrog„ repeating jug a rum jug a rum like a bass fiddle. These three popular characters belong in the genus Rana of the Family Ranidae.