Alligator Essay Research Paper The American Crocodile

Alligator Essay, Research Paper

The American Crocodile (Crocodiles acutus) Crocodylus acutus, or more commonly

referred to as the American crocodile, ".is the second most widely

distributed of the New World crocodiles, ranging from the southern tip of

Florida, both the Atlantic and Pacific Coasts of Southern Mexico, as well as the

Caribbean islands of Cuba, Jamaica, and Hispaniola" (1 Species). These

areas provide the perfect climate for these endangered species that have roamed

the earth for over 200 million years. Florida is known for its large population

of American alligators, which are often confused for the rare American

crocodile. However, there are vast differences between the two species. Hunted

for their hides and the changing of their habitat to beach front property is

slowly pushing the American crocodile out of Florida, the only place it is found

in the United States. "For 190 million years before the first humans

evolved, huge populations of crocodilians, in more or less their present form,

inhabited the waters and shorelines of rivers, lakes, swamps, and estuaries of

tropical and subtropical lands. Today they represent the last true survivors of

the huge reptiles that once dominated the seas and landmasses of Earth for over

200 million years" (6 Levy). However, ".It is inappropriate to treat

crocodilians as living fossils whose inferiority forced them into a marginal

ecological role as amphibious predators in a world now dominated by mammals. In

fact, they are highly specialized for their particular mode of life and have

undergone considerable changes during their long evolutionary history."

(14 Ross). "Among living vertebrates, crocodilians are most closely related

to birds rather than to lizards" (14). Even though these two groups are now

adapted to different modes of life, they both have an elongate outer ear canal,

a muscular gizzard, and complete separation of the ventricles of the heart.

"Crocodilians are the most advanced of all reptiles. They are elongated,

armored, and lizard-like, with a muscular, laterally shaped tail used in

swimming. The snout is also elongated, with the nostrils set to the end to allow

breathing while most of the body remains submerged under water". "The

success of the Crocodile is evidenced by the relatively few changes that have

occurred since crocodilians first appeared about 200 million years ago".

The Crocodile belongs to the family Crocodylinae, which consists of those

organisms sharing common crocodilian traits. This Family is further divided into

three subfamilies: Alligatorinae (alligators), Gavialinae (gharial), and

Crocodylinae (crocodiles). Very often the American alligator (Alligatorinae

mississippiensis) is confused for an American crocodile, even though these two

species are of the same family they are different in many ways. The alligator

has a much broader snout and the crocodile a much narrower snout-

".narrower snouts usually indicating fish eating-species". Another

characteristic seen in the American crocodile and not the alligator is the front

two teeth that penetrate the upper jaw from below as they grow. These teeth are

one of the major differences between crocodiles and alligators. A not so

recognizable difference between the American crocodile and alligator is the

crocodile’s ability to regulate saltwater balance in their body. Crocodiles

maintain salt concentrations in their body fluid at the typical level of other

vertebrates, which is about one-third that of seawater. "The osmoregulatory

problems posed by life in fresh or saline waters are related to the amounts of

water and salts exchanged across various body surfaces. Loss of salts and water

occurs in feces and urine, through respiration, excretion from salt glands in

the tongue, and through the skin. The ability of the American crocodile to

tolerate salt water is related to their low rate of water loss, low rate of

sodium uptake, the ability to excrete excess sodium, and their ability to

osmoregulate regularly behaviorally by not drinking saline water or by seeking

fresh water after feeding in saline areas". [The American crocodiles will

not drink seawater even when they are dehydrated and the American alligator

will. However, the alligator does not have the ability to excrete excess

sodium]. While the American Crocodile is able to regulate its salinity it is not

able to maintain a constant body temperature. Crocodiles, like all reptiles, are

cold blooded or pokilothermic. "Crocodiles utilize a complex series of

physiological and behavioral mechanisms to maintain an even body temperature.

When their body temperature drops, they use solar radiation to heat their bodies

as they emerge from the water to bask in shallow waters or on the shoreline. As

their temperature ris

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