These are organized by a classification scheme developed exclusively for Cosma. More…
frog : any of various largely aquatic leaping anuran amphibians (such as ranids) that have slender bodies with smooth moist skin and strong long hind legs with webbed feet — Webster
Frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura. The oldest fossil “proto-frog” appeared in the early Triassic of Madagascar, but molecular clock dating suggests their origins may extend further back to the Permian, 265 million years ago. Frogs are widely distributed, ranging from the tropics to subarctic regions, but the greatest concentration of species diversity is in tropical rainforests. There are approximately 4,800 recorded species, accounting for over 85% of extant amphibian species. They are also one of the five most diverse vertebrate orders.
The body plan of an adult frog is generally characterized by a stout body, protruding eyes, cleft tongue, limbs folded underneath, and the absence of a tail in adults. Besides living in fresh water and on dry land, the adults of some species are adapted for living underground or in trees. The skin of the frog is glandular, with secretions ranging from distasteful to toxic. Warty species of frog tend to be called toads but the distinction between frogs and toads is based on informal naming conventions concentrating on the warts rather than taxonomy or evolutionary history; some toads are more closely related to frogs than to other toads. Frogs’ skins vary in color from well-camouflaged dappled brown, grey and green to vivid patterns of bright red or yellow and black to advertise toxicity and warn off predators.
Frogs typically lay their eggs in water. The eggs hatch into aquatic larvae called tadpoles that have tails and internal gills. They have highly specialized rasping mouth parts suitable for herbivorous, omnivorous or planktivorous diets. The life cycle is completed when they metamorphose into adults. A few species deposit eggs on land or bypass the tadpole stage. Adult frogs generally have a carnivorous diet consisting of small invertebrates, but omnivorous species exist and a few feed on fruit. Frogs are extremely efficient at converting what they eat into body mass.
They are an important food source for predators and part of the food web dynamics of many of the world’s ecosystems. The skin is semi-permeable, making them susceptible to dehydration, so they either live in moist places or have special adaptations to deal with dry habitats. Frogs produce a wide range of vocalizations, particularly in their breeding season, and exhibit many different kinds of complex behaviours to attract mates, to fend off predators and to generally survive. — Wikipedia
Frogs and Reptiles News -- ScienceDaily Snakes, lizards, alligators, frogs and toads. From habitat information to frogs in stem cell research, you will find all the reptile and amphibian news here.
Snake fungal disease alters skin microbiome in...
on August 14, 2018 at 7:33 pm
In the first study of its kind, researchers characterized the skin microbiome of a population of free-ranging snakes to begin to understand how the animals' environmental microbial community may promote disease resistance as well as how it may be disrupted by infection. […]
Scientists get new tool to track new pathogen...
on August 14, 2018 at 7:09 pm
An undergraduate researcher has developed a method to screen frogs for an infectious disease that has been linked to mass die-offs of frogs around the world. Thanks to her method, scientists will be able to track the disease and try to figure out why it is triggering the deaths. […]
When it comes to regrowing tails, neural stem...
on August 13, 2018 at 8:05 pm
It's a longstanding mystery why salamanders can perfectly regenerate their tails whereas lizard tails grow back all wrong. By transplanting neural stem cells between species, researchers have discovered that the lizard's native stem cells are the primary factor hampering tail regeneration. […]
In apoptosis, cell death spreads through...
on August 9, 2018 at 6:12 pm
In a cell, death is akin to falling dominoes: One death-inducing molecule activates another, and so on, until the entire cell is shut down, a new study finds. […]
A new earless pygmy toad discovered on one of...
on August 8, 2018 at 5:41 pm
Due to many years of conflict, the biodiversity of Angola remains one of the least known in Africa. Recently, scientists from Angola, Portugal, and the United States conducted a series of field expeditions to document this country's amphibian and reptile species. One newly discovered species is a pygmy toad from the isolated Serra da Neve, the second highest peak in Angola. It differs from all close relatives in lacking an external and middle ear. […]