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Frogs Essay Research Paper Frogs Frog is

Frogs Essay, Research Paper


Frogs


Frog is the common name for a species of


amphibian that also includes toads. A very common


question is whats the difference between frogs and


toads? , the answer: none, except for the fact that toads


lack the powerful legs that frogs have. Where can frogs


and toads be found? , one might ask. They live in all


parts of the world, except for Antarctica, but are mostly


found in tropical areas. Frogs are small animals with


smooth moist skin, and big eyes that can see in almost


any direction. Most species have webbed feet and


powerful legs making them good jumpers, and excellent


swimmers. A frogs tongue is attached to the front of it s


mouth instead of the rear, and most frogs are very vocal,


especially the male frogs.


As a frog grow, it goes through many changes.


Starting out as a tadpole, and morphing into a frog.


Most frogs lay their eggs in water. Others will lay their


eggs some where safe, then carry them to water where


they hatch into tadpoles. At this stage they have gills,


no legs, and a tail. As they mature, their gills and tail


disappear, and they develop lungs and legs. This period


of tadpole life can be divided into three stages. The first


stage, called premetamorphosis, lasts about 50 days


(Patent 54). The second stage, in which the hind legs


grow, is called prometamorphosis, and lasts about 21


days. When the legs are about as long as the body, the


third stage, which is called metamorphic climax, and


takes place very rapidly, begins. During this last stage,


which lasts about a week, many great changes occur.


They lungs complete their development, and the gills


disappear. The skin gets thicker, nostrils form, and the


tail is completely resorbed.


Most frogs prefer moist regions, and many kinds


live in the water. Because frogs absorb oxygen in water


through their skin, they can stay underwater for long


periods of time. A frogs body temperature depends on


it s surroundings, and during cold weather, frogs dig


burrows in mud and hibernate. During hibernation, the


frog needs little oxygen and no more food than is already


in it s tissues. During intense heat, a frog might


estivate, or in other words, lie in a state of torpor during


the heat, after burying themselves in sand and clay.


Frogs are carnivores. They eat just about anything


smaller than then that moves. A frog thinks like this: If


it s smaller than itself and moves, eat it. If it s the same


size, mate, or attempt to mate (this gets some frogs in


lots of trouble). If it s bigger than itself, run. Their diet


may include insects, worms, spiders, or even centipedes.


Aquatic frogs sometimes eat other frogs, tadpoles, and


small fish. Large frogs can eat can eat stuff as big as


mice and snakes. Sometimes a frog eats something too


big to swallow all at once, and will leave it sticking out


of its mouth ingesti

ng it gradually or even choking and


regurgitating it. So virtually, the size of a frog s dinner


is determined by the size of it s mouth. If a frog eats


something poisonous or bad for them, they can throw up


their entire stomach and wipe it with their right front leg.


Frogs help out humans in many ways. Toads are


used world wide as pest control in gardens and on farms.


One toad alone can consume thousands of insects.


Frogs have been used as food for centuries. Efforts have


been made to harvest frogs, but most frogs eaten today


are taken from their natural habitat. People in South


America, the South Pacific, Philippine Islands, and parts


of Africa savor frogs, and consider them a delicacy. The


Chinese and French are lovers of frogs legs. One of the


reasons frogs legs are so expensive is the great demand


for frogs in scientific and medical laboratories. Because


their skeletal, muscular, digestive, nervous, and other


systems are similar to those of higher animals, frogs are


very important in these in these fields of research.


One large and nearly worldwide family of frogs are


the true frogs, many species combined that are well


known (Encarta True Frogs). The Bullfrog is one of the


largest true frogs in North America (Barker 150). It


weighs up to 1.2 pounds and has a total length of 15


inches. One of the most common North American


species is the leopard frog (Barker 154), which is easily


recognized by the numerous black, often light-edged


spots on the back and legs. Most true frogs stay close to


ponds and streams, but the North American wood frog


(Stebbins 135), a small redish-brown species with


mask-like black bands on the head, wander far away


from the water. The green frog is another common


species in North America and despite their name, some


green frogs are brown. Two well-known true frogs of


Europe are the common European frog, which resembles


the wood frog, and the edible frog, a popular food in


Europe. The African Giant Frog, the largest of all frogs,


which grows as long as 26 inches and weighs as much as


10 pounds, is also a true frog . The smallest frog is


probably the Psyllophyne Didactyla from Brazil which is


about 9.8 mm as an adult.


The frogs and other amphibians of North America,


and those of other continents too, are important in the


way all wild things are important. They are also a living


resource that needs protection and greater understanding


to appreciate its true worth.


Today there is a strong effort by all forms of


government to set aside areas that furnish the sort of


environments required by many forms of wildlife,


including frogs. Private organizations and individuals


too have established many special areas mostly free from


conditions that disturb natural habitats. People are


finally realizing that, hey, frogs aren t such bad guys and


maybe we should keep them around.


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