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What is Alligator?

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An alligator is a crocodilian which is an order of large, predatory and semi-aquatic reptiles. In the further division of the order of Crocodilian, there is a family named Alligatoridae. Under this family of Alligatoridae comes the genus Alligator.  The two living species of this genus are The American alligator (alligator scientific name - Alligator mississippiensis) and the Chinese alligator (alligator scientific name - Alligator sinensis). Apart from this, there are several other alligator species that belong to this genus but have become extinct and are identified by the fossil remains. One interesting fact about the alligator is that they are said to have first appeared on earth about 37 million years ago.

Alligators are generally carnivores and people generally consider the alligator and a crocodile as the same species because of certain similarities in their appearance and their predatory nature. But it is not the case. Alligators and crocodiles are different species with significant characteristic differences between them which will become clear going further.

Where Do Alligators Live?

Alligators are generally found in three countries: The United States, Mexico, and China. The American alligator is native to The United States and Mexico and subsequently, The Chinese alligator is native to China. 

It is noteworthy that as the two extant alligator species are from different continents they have different living conditions. The American alligator habitat consists of freshwater environments such as ponds, marshes, wetlands, rivers, lakes, swamps and brackish waters. When they construct holes in the ground in the wetlands the alligator habitat increases plant diversity and provides habitat for other animals as well. Hence, the alligator species are important for maintaining ecological diversity in the wetlands.

Currently, there are over a million alligators in the states of Florida and Louisiana. The southern part of America and the northern part of Mexico is thus found to harbour this particular alligator species.

On the other hand, the Chinese alligators are extremely endangered alligator species. They are generally found in the Yangtze River of China. The number of these alligators in the wild only goes up to a few dozens. Several of the Chinese alligator species are generally found in zoos around the world as compared to the wild. Attempts for the preservation of the species of this alligator are made by the Rockefeller Wildlife Refuge and Miami Metrozoo. 

There are two kinds of white alligators: albino and leucistic. They are extremely rare and almost difficult to be found in water. They can only survive in captivity and are very few in number. Some of them are with the Aquarium of the Americas in New Orleans.

The images of the American and Chinese alligator is shown below:

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About Alligator Anatomy

One of the most interesting alligator facts is that they have unidirectional movement of air through the lungs like the birds. In an alligator, the air in the lungs moves in only one direction through a circuit of parabronchi. The air first enters the outer branch of the lungs either through the mouth or other respiratory organs, passes through the circuit of parabronchi and exits the lung through the inner branch. Around the parabronchi, there is an extensive network of vascular tissues that are responsible for carrying oxygen to the different parts of the body. The oxygen exchange in an alligator takes place around the parabronchi in these vasculators. 

Another anatomical feature of the body of an alligator is the armour of bony plates. These bony plates are composed of dermal tissues. These bones have a high vascular network and aid in calcium balance, both to neutralise acids when the alligator is underwater and unable to breathe. The calcium is utilised in the eggshell formation. 

A well-known of the alligator facts is that they have muscular flat tails that propel them while swimming and for defence purposes. The eyes, ears, and nostrils are on the top of their long head and are projected above the water surface when they are floating in a water body.

Life-Style of Alligators

Alligators are territorial animals. The large alligators especially are territorial and tend to remain alone. On the other hand, small alligators may come together and live in groups but with a size limit on the number of members. 

Alligators have the capacity to move on land by two mechanisms. They are: “sprawl” and “high walk”. The sprawl refers to their movement when they slide with their belly touching the ground on the wet surfaces generally to slide into the river or to get to the high walk position on the land. The high walk refers to their movement on all four limbs. Although alligators are known for the capability of rising on the hind legs and taking a semi-step forward, they cannot walk only on the two hind legs. 

An alligator can catch short bursts of speed in very short lunges. They generally kill prey that is small and capable of death on the first go itself. The usual diet of an alligator includes larger fish such as gars, turtles, mammals, certain birds and reptiles, etc. This diet is dependent upon their stage of growth. The given diet is that of an adult alligator whereas a young alligator will feed on small fish, insects, snails and worms. Once they grow to a length of six feet and become an adult they go for larger kills sometimes such as dogs. They may kill larger prey by grabbing them and then dragging them inside the water so that they die of suffocation. Sometimes, the alligators perform “death rolls” i.e. spinning or convulsing wildly with the help of their tail orientation at a particular angle to their body which in turn tears off the biteable size chunks of the prey. An important aspect of the death roll is that it cannot be performed if the tail is fixed. 

Alligators have strong muscles for closing their jaws. This helps them to entrap the prey easily and swiftly and proceed for the kill. But the strength that the jaw muscles of an alligator have while closing they lack similar strength while the opening of the jaw. Due to this, any human is able to hold off the mouth of the alligator and keep it shut by binding it with a thread of a duct-tape. Although alligators don't directly attack humans because they are usually afraid of humans, they can attack when felt threatened. With the increased poaching and destruction of alligator habitats due to human activities, certain cases are coming up of an alligator attacking a human. 

After maturing around the length of six feet alligators are ready for mating. This comes around the time of late spring. In April and May alligators form these bellowing choruses, where a large number of alligators come together and perform the so-called “alligator dances”. In summer, the female alligator builds a nest of vegetation utilizing the heat from the decomposition of vegetation for the hatching of the eggs. The sex of the alligator is decided by the temperature of incubation of the egg. If the egg is incubated at 30° C for the first 21 days (the time period for sex determination), then the young alligator hatched is generally a female. And if the incubation temperature reaches 34° C and beyond, the young alligator is a male. The baby alligator’s tooth helps it to break free from the egg. Usually, the mother defends the nest for about a year if the young ones stay around the nest.

Differences Between Crocodile and Alligator

Given below are the differences between the alligator and crocodile species. These physical qualities help in determining whether the given semi-amphibian predator is a crocodile or an alligator

  • Teeth: This is the easiest spottable difference between an alligator and a crocodile. The teeth of the alligator in the lower jawline fit into the sockets in the upper jaw because of which only the teeth from the upper jawline are visible. This is not the case with a crocodile as the teeth in the lower jawline of a crocodile fit into the grooves on the outside of the top jaw, making both the upper and lower jaw teeth visible. 

  • Nose and jaw shape: Alligators have a U-shaped nose while the crocodile has a V-shaped nose. The snout of the alligator is broad and wide as a shovel while the snout of the crocodile is more pointed forming a V-shape. 

  • The functioning of salt glands: The salivary glands of the animals in the crocodilian order excrete salts and hence are called salt glands. This ability allows these animals to survive and navigate through salty water habitats. But over a period of time, this ability has been lost by the alligator species while the same has been retained by the crocodiles and gharials. Due to this, the alligator habitat has become restricted to freshwater regions. 

  • Integumentary sense organs: There are pit-like sensory organs present in the alligators and crocodiles which are known as integumentary sense organs (ISO’s). These sensory organs provide them with a unique ability to detect pressure changes in the water environment which in turn is beneficial for them in hunting prey and their own survival. The difference is that in crocodiles these organs are present over the whole body whereas in the case of alligators it is only present on their upper and lower jaws. 

  • Aggressiveness: Generally, alligators are less aggressive than crocodiles. Also, a crocodile might attack a human considering it to be a prey whereas an alligator generally avoids doing so unless threatened for survival. There are hundreds of reports of deadly encounters between Nile crocodiles and humans as compared to very few such encounters between humans and alligators. 

Advantages to the Humans

Alligators have been raised by humans for commercial purposes and as well as their meat. The commercial purposes include their meat and especially the skin which when tanned can be used in the production of luggage, handbags, shoes, belts and other leather goods. Alligators also serve as the main attraction for the ecotourism industry. Tourists may take up swamp tours to sight an alligator. Along with this, the alligators are also used as natural pest control agents by humans for controlling the populations of rodents such as coypu and muskrats.

Conclusion For What is Alligator?

This article gives a very brief overview of what is alligator. An alligator is a genus in the family of Alligatoridae under the order Crocodilian. Although, having similar characteristics to crocodiles, one can now understand and appreciate their significant differences. Also, for the awareness of conservation of endangered species the Chinese alligator species underline the need of the hour. They are currently included in the critically endangered list of the International Union for Conservation of Nature and Natural Resources (IUCN).

FAQ (Frequently Asked Questions)

1. What is the Difference Between Crocodile and Alligator?

Ans: There are two most noticeable differences between an alligator and a crocodile. Firstly, the snout in an alligator is broad and shovel-like giving it a U-shape. The same snout for the crocodile is pointed and forms a V-shape. The teeth in the lower jaw of the alligator remain hidden when the mouth is closed, whereas the teen from both the upper and lower jaw of the crocodile are visible giving it a teethy grin.

2. Which is the Most Dangerous - Alligator or Crocodile?

Ans: Out of 23 species of crocodiles, six are found to be hostile to humans. Out of the existing two species of alligators, none are hostile to humans. Crocodiles are generally considered to be more aggressive than alligators. Also, crocodiles deem humans as their prey and usually attach when sighted, but an alligator avoids any such engagement as they are generally afraid of humans unless threatened for survival.

3. How Many Babies Does an Alligator Have?

Ans: An alligator’s clutch or the number of eggs laid during breeding season is 38. Out of these 38, 24 have the possibility of surviving any predators and emerge as live hatchlings. From these 24, only 10 baby alligators survive for a year and of these only 8 will become subadults (4 feet in length).