Tell Me > Curiosity Corner > Animals > Are alligators really dinosaurs?

Are alligators really dinosaurs?

 

While fatal attacks are out of the norm, non-fatal attacks, unfortunately, are not as rare. The fact is: alligators can be dangerous. An alligator's brain weighs only eight or nine grams; it would take up only one-half of a tablespoon. This lack of brainpower means there is no such thing as a "nice alligator." If it's hungry, an alligator will eat anything that moves, including humans.

Danger and scariness aside, alligators are amazing animals. They've been around for millions of years, and they're about as close as we'll probably ever get to seeing a living dinosaur. So what is it about alligators that's allowed them to survive for so long? Let's find out.

-- American alligators are reptiles. They are members of the Crocodylia order. In this order, there are 23 different species, including the American alligator, Caimans and a variety of crocodiles. 

-- The basic Crocodylia body form has been around for more than 180 million years, making alligators and crocodiles living dinosaurs. 

-- All of these animals have the same basic layout: big heads, long, lizard-like bodies, four stubby legs and long tails. 

-- Male alligators are, on average, about 11 feet long and weigh approximately 600 pounds. Females are, on average, about eight feet long and weigh about half as much as male alligators. Males can actually get much larger. A 1,000-pound alligator is not unusual. 

-- While there are reports of one alligator, held in captivity, that lived to be more than 100 years old, something like 40 years might be a more typical lifespan for alligators living in the wild.

-- Alligators are fresh-water animals and can be found in lakes, ponds, rivers and irrigation canals. Because they are cold-blooded reptiles, alligators are not big fans of cold weather. This limits their range to the warmer, wetter areas in the southeastern United States from Texas to North Carolina.

-- Since alligators are cold-blooded, they have very small lungs compared to mammals. This means that, when running, fighting or wrestling, alligators are using anaerobic respiration (without oxygen) to power their muscles. A large alligator can exert itself for at the very most 30 minutes or so before it is completely exhausted. Then it will take several hours for it to recover. 

-- Alligators are armor-plated. Bony plates inside the skin, called osteoderms or scutes, make the skin very hard to penetrate. Each spike or ridge along the back of an alligator is made by a piece of bone in that section of skin.

-- Even though alligators are huge and cold-blooded, they can be surprisingly fast, with a top speed of 11 miles per hour over short distances. For comparison, the fastest humans running at world-record times in a 100-meter dash are running about 20 miles per hour, but a typical adult human is no faster than an alligator. This makes it possible for an alligator to escape from most situations on land and get into the water. It also makes it possible for an alligator to overtake an unsuspecting human.

-- Alligator eyes have two sets of eyelids. The outer lids are like human eyelids. They're made of skin and close top-to-bottom. The inner lids are clear and close back-to-front. While an alligator is just hanging out or swimming, these inner eyelids protect the alligator's eyes and provide clearer vision in the underwater environment.

-- When swimming underwater, alligators are watertight. Flaps close off the ears and nostrils, the inner eyelids protect the eyes, and a special flap called the palatal valve closes at the back of the throat to keep water out of the throat, stomach and lungs. 

-- Alligators can stay underwater for a pretty long time. A typical dive might last 10 to 20 minutes. In a pinch, an alligator can stay underwater for two hours if it is at rest. And, in very cold water, an alligator can last up to eight hours submerged.

-- When it's time to eat, alligators are neither hunters nor gatherers. They are lurkers. They wait for something edible to pass nearby and they lunge at it with incredible speed. 

-- Using their tails, alligators can push themselves up to five feet out of the water to snag small animals in low-hanging tree branches. 

-- Alligators will eat almost anything they can capture -- fish, turtles, frogs, birds, small mammals, and sometimes even larger mammals like deer. 

-- Alligators capture all of these creatures by lurking in the water. When lurking, only the eyes and nostrils are above the waterline. This posture will make an alligator lurking in the shadows at a pond's edge nearly impossible to detect. An alligator can sit like this for hours waiting for something edible to wander nearby. When its prey gets close enough, the alligator moves with startling speed.

-- Besides its eyes and ears, alligators are equipped with skin sensors that are incredibly sensitive to vibration. These tiny black dots make it possible for an alligator to detect anything entering the water or disturbing the surface of the water anywhere nearby. 

-- Once an alligator captures something, it will hold it in its mouth and drag it underwater to drown it. It must then get back above water to swallow it -- otherwise, the alligator's stomach and lungs would fill with water. 

-- Using its incredibly powerful jaws (which are able to exert up to 2,000 pounds per square inch), an alligator will break bones or crush shells (in the case of turtles) to create a chunk of flesh that can fit down its throat. Then it will raise its head, open the palatal valve and swallow the piece whole. 

-- An alligator can digest anything it swallows -- muscle, cartilage and even bone are all digested completely. 

-- Unlike humans, alligators don't have to eat very often. A typical feeding schedule for alligators living in the wild is about one feeding per week. Excess calories are stored in fat deposits at the base of the alligator's tail. 

-- Incredibly, by burning fat reserves, it is possible for an alligator to last more than two years between feedings.

-- When it gets cold in the winter, alligators slow down. Below 70F or so they stop feeding, and when it gets much colder, alligators dig out a den in the bank of a pond or river and go dormant until it warms up again. 

-- Alligators can even survive freezing conditions. They have been known to rise to the surface if the water is about to freeze, with their nostrils above the surface. This allows them to breathe through the ice as it forms. In extreme cases, they get frozen into the surface of the pond for several days and then swim free when the ice melts.