Hyla

Hyla is a genus of tree frogs in the family Hylidae. Over the years, scientists have changed their minds about which frog species should be in "Hyla" and which should be in "Litoria", "Ranoidea" or other genera. At one time, "Hyla" had more than 300 species from Europe, Asia, Africa, and across the Americas. Now, "Hyla" has only 17 extant (living) species. They are from Europe, northern Africa and Asia. The earliest known fossil from a "Hyla" frog is †"Hyla swanstoni" from the Eocene. The fossil was found in Saskatchewan, Canada, but it is not clear whether we would consider "swanstoni" a "Hyla" frog today.
Josephus Nicolaus Laurenti made the genus in 1768. He named it after Hylas from Greek mythology. Hylas was a friend of Hercules. Even though the mythological person Hylas was male, the name "Hyla" is given the feminine grammatical gender.
Some people say this word comes from the Greek word ("", "forest" or "wood"), but it does not.
Mating systems.
Female choice based on male calling.
In most "Hyla" frogs, the male frogs sing, and then the female frogs choose which male to mate with based on their songs. But females from different species like different things about male frogs' voices. Female "H. versicolor", for example, choose males whose calls last longer. Female "H. arborea" choose males who show up to sing in the same place for many nights.
Male-male contests.
In some "Hyla" frogs, the male frogs fight and compete. Male "H. versicolor" frogs show up where the females like to go. This behavior, called lekking, is common in many species of "Hyla". In order to sing clearly, the males need to be a certain distance apart from each other. When one male gets too close to another male's singing place, the two males may fight or do something else that is like fighting. Male "H. versicolor" sometimes show off to each other before they fight, so they can see whether they are likely to win first.
Indirect selection.
Indirect selection is when one partner chooses a mate based on just one thing that is related to how fit and healthy the mate is all together. "H. arborea" is a frog that is awake at night, and the females listen to the males sing and then choose one, so the frogs must be able to hear well. These frogs can also see well in low light. This ability to see may be related to how females choose males. Scientists say female "H. arborea" choose males with more brightly colored vocal sacs. They think colorful vocal sacs may show that the frog has enough carotenoids in the food it eats. This may mean the male frog is better at finding food than other frogs, and he might pass on some of this skill to his offspring.