ALLIGATOR




The alligator is an ancient creature which first appeared during the Oligocene epoch about 37 million years ago. Today there are two living alligator species: the American alligator - Alligator mississippiensis, and the Chinese alligator - Alligator sinensis. However, there are several extinct species of alligator are known from fossil remains.

Where do Alligators live?

Not to be confused with crocodiles, alligators are only native to the United States and China. In America they are found in the southeast United States: all of Florida and Louisiana, the southern parts of Georgia, Alabama and Mississippi, coastal South and North Carolina, Eastern Texas, the southeast corner of Oklahoma and the southern tip of Arkansas. The majority of American alligators inhabit the states of Florida and Louisiana, with over a million alligators in each state.

American alligators live in freshwater environments, such as ponds, marshes, wetlands, rivers, lakes, and swamps, as well as brackish environments. The Chinese alligator currently is found only in the Yangtze River valley and is extremely endangered, with only a few dozen believed to be left in the wild. Indeed, far more Chinese alligators live in zoos around the world than can be found in the wild.

So, just what do alligators eat?

What alligators eat will depend on its age and how big it is. When young, alligators will eat small fish, insects, snails, crustaceans, and worms. As they mature into a larger beasts,  they will eat progressively larger prey. This will include larger fish such as gar, turtles, various mammals such as water birds and deer, and other reptiles.  They will even consume carrion if they are sufficiently hungry. Adult alligators can take razorbacks and deer and are well known for killing and eating smaller alligators!

 Alligators' main prey are smaller animals that they can kill and eat with a single bite. Alligators may kill larger prey by grabbing it and dragging it into the water to drown. Alligators consume food that can not be eaten in one bite by allowing it to rot, or by biting and then spinning or convulsing wildly until bite-size chunks are torn off. This is referred to as a "death roll." Critical to the alligator's ability to initiate a death roll, the tail must flex to a significant angle relative to its body. An alligator with an immobilized tail cannot perform a death roll.

In areas where human populations encroach on alligator territories larger alligators are also known to ambush dogs. Attacks on humans are rare but not unknown. Unlike large crocodiles, alligators do not immediately regard a humans as prey, but they may still attack in self-defence if provoked.

Due to the design of their teeth alligators are unable to chew their food so their stomachs also often contain gizzard stones which are used to help break down and digest their food . 

Alligator behaviour

Large male alligators are solitary territorial animals, although smaller alligators can often be found in large numbers close to each other.

The mating season is in late spring. In April and May, alligators form so-called "bellowing choruses". Large groups of animals bellow together for a few minutes a few times a day, usually one-three hours after sunrise. The bellows of male American alligators are accompanied by powerful blasts of infrasound produced by sacs in their chins.

Another form of male display is a loud head-slap. Recently it was discovered that on spring nights alligators gather in large numbers for group courtship, the so-called 'alligator dances'.

In summer, the female builds a nest of vegetation where the decomposition of the vegetation provides the heat needed to incubate the eggs. The sex of the offspring is determined by the temperature in the nest and is fixed within 7 to 21 days of the start of incubation. Incubation temperatures of 86 °F (30 °C) or lower produce a clutch of females; those of 93 °F (34 °C) or higher produce entirely males.

Nests constructed on leaves are hotter than those constructed on wet marsh and, thus, the former tend to produce males and the latter, females. The natural sex ratio at hatching is five females to one male. Females hatched from eggs incubated at 86 °F (30 °C) weigh significantly more than males hatched from eggs incubated at 93 °F (34 °C).

 The mother will defend the nest from predators and will assist the hatchlings to water. She will provide protection to the young for about a year if they remain in the area. The largest threat to the young are adult alligators.

Baby alligators have an egg tooth that helps them get out of their egg during hatching time. Predation by adults on young can account for a mortality rate of up to fifty percent in the first year. In the past, immediately following the outlawing of alligator hunting, populations rebounded quickly due to the suppressed number of adults preying upon juveniles, increasing survival among the young alligators.

What is the difference between Alligators and Crocodiles?

Lets face it, crocodiles, alligators - they both look the same. Beady eyes, scary teeth and loads of warty skin - what else do you need to know? Well, they must be different otherwise they wouldn't have different names, and with just a closer look - and a little help from a suitable expert - you can see for yourself just how different they truly are.

So, just what is the difference between a crocodile and an an alligator?

The first difference between a crocodile and an alligator is that they are from different families. While both are grouped within the crocodilian family, crocodiles are from the crocodylidae family, while alligators and caiman are from the alligatoridae family.

In terms of physical differences, the easiest way to tell the difference between the two is that a crocodile has a very long, narrow, V-shaped snout. In contrast, the alligator's snout is wider and U-shaped. Because of the wide snout of the alligator it packs more crushing power to eat prey like turtles that constitute part of its diet. The narrow crocodile snout, although still very powerful, is not really suited for prey like turtles but is very versatile for fish and mammals.

Another important difference between the crocodile and the alligator is that the crocodile's upper and lower jaws are nearly the same width, so the teeth are exposed all along the jaw line in an interlocking pattern - even when the mouth is closed. They also have an enormous 4th tooth on the lower jaw that is accommodated by depressions in the upper jaw just behind the nostrils.

An alligator, on the other hand, has a wider upper jaw, so when its mouth is closed the teeth in the lower jaw fit into sockets of the upper jaw, hidden from view. Only the teeth of the upper jaw are exposed along the lower jaw line. Even the enormous 4th tooth on the bottom jaw, which is exposed in a crocodile, is hidden in the alligator.

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