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World's 7 Most Amazing Toads And Frogs

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1) Cane Toad -
2) Kihansi Spray Toad -
3) Suriname Toad -
4) Golden Toad -
5) Emei Mustache Frog -
6) Brazilian Horned Frog -
7) Vietnamese Mossy Frog -

A toad is any of a number of species of amphibians in the order Anura (frogs) characterized by dry, leathery skin, short legs, and snout-like parotoid glands.

A distinction between frogs and toads is not made in taxonomy, but is common in popular culture, in which toads are associated with drier skin and more terrestrial habitats than animals commonly called frogs. In taxonomy, toads are found in the families Bufonidae, Bombinatoridae, Discoglossidae, Pelobatidae, Rhinophrynidae, Scaphiopodidae, and Microhylidae. A group of toads is called a knot.

The bumps on a toad's skin help the animal to blend into its environment visually by breaking up its outline.[citation needed] Although the parotoid glands are sometimes referred to as "warts", they are present on healthy specimens and are not a result of infection.

Frogs are a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (Ancient Greek an-, without + oura, tail). 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 found in tropical rainforests. There are about 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. 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 colour 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 lifecycle 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, which makes them an important food source for predators. Frogs are a keystone group in the food web dynamics of many of the world's ecosystems. The skin is semipermeable, 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.

Frog populations have declined significantly since the 1950s. More than one-third of species are considered to be threatened with extinction and over 120 are believed to have become extinct since the 1980s.[1] The number of malformations among frogs is on the rise and an emerging fungal disease, chytridiomycosis, has spread around the world. Conservation biologists are working to understand the causes of these problems and to resolve them. Frogs are valued as food by humans and also have many cultural roles in literature, symbolism, and religion.
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