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.
The mystery of lime-green lizard blood
on May 16, 2018 at 9:23 pm
Green blood is one of the most unusual characteristics in the animal kingdom, but it's the hallmark of a group of lizards in New Guinea. The muscles, bones and tongues of these lizards appear bright, lime-green due to high levels of biliverdin, or a green bile pigment, which is toxic and causes jaundice. Surprisingly, these lizards remain healthy with levels of green bile that are 40 times higher than the lethal concentration in humans. […]
How turning down the heat makes a baby turtle male
on May 11, 2018 at 12:37 am
Scientists have started to crack the 50-year-old puzzle of how temperature turns baby turtles male or female. Researchers show that cooler egg incubation temperatures turn up a key gene called Kdm6b in the turtle's immature sex organs. This in turn acts as a biological 'on' switch, activating other genes that allow testes to develop without altering the underlying genetic code. […]
Global trade spreads deadly frog disease from Asia
on May 10, 2018 at 7:00 pm
New research has revealed a deadly disease that threatens the survival of the world's frogs originated from East Asia, and global trade was almost certainly responsible for the disease's spread. […]
Climate change may even threaten one of the...
on May 9, 2018 at 4:16 pm
Bahamian anole lizards are popular exotic pets and are found throughout the Western Hemisphere, suggesting that they are extremely adaptable creatures. A new study suggests that their adaptability may not extend to the temperature changes predicted by climate change models. […]
New evidence that bullfrogs are to blame for...
on May 7, 2018 at 12:48 pm
In the 1890s, settlers crossed the Rocky Mountains seeking new opportunities -- and bearing frogs. A new study draws a link between that introduction of American bullfrogs (Rana catesbeiana) to the western half of the United States with the spread of a fungus deadly to amphibians. The work highlights the catastrophic results of moving animals and plants to new regions. […]