Although alligators and crocodiles are similar in appearance, they are vastly different creatures.
Both alligators and crocodiles are reptiles and carnivores.
They tend to hunt similarly and have the same sort of diet.
However, there are several differences between them that make them distinct species from one another.
Here are the main differences between a crocodile and an alligator.
Crocodile Vs. Alligator (What’s the Difference?)
It can be difficult to tell the color of an alligator and crocodile because they’re usually in murky waters.
They prefer these types of waters because it allows them to camouflage themselves within them.
When an unsuspecting bird or animal swims by, it takes little effort on their part to snap into action.
However, due to the murky water and mud-caked bottom of the body of water, it isn’t always easy to tell what color the creature is.
Color can be a distinguishing mark between an American Crocodile and an American Alligator, though.
Crocodiles come in an array of colors that help them match their environment.
The most common colors of crocodiles in America include:
- Slate grey
They also tend to have yellow or white undersides.
This helps them stay camouflaged both on the surface of the water and beneath it.
The area in which the crocodile lives also determines its colors.
Saltwater crocodiles, for example, tend to be green and live in bodies of water that have a green shade to them.
Because there’s sometimes a lot of seaweed and algae in saltwater, it turns the area around it green.
This allows the saltwater crocodile the perfect environment it needs to hunt quietly.
The Nile crocodile also differs in colors.
It has deep green scales with speckles on it.
This helps it match the colors and sediment of the Nile River.
Alligators come in similar shades, but they’re actually quite different.
They tend to be far darker than the crocodile and have less color variation.
Most often, alligators are dark green.
When wet or under the water, their scales even appear black.
Generally, they tend to be darker than crocodiles.
Their colors are different because of their habitats.
Crocodiles live in areas that have a lot of algae.
Hence, they’re greener in color.
Alligators prefer to live in swamps and lakes.
Their coloration tends to run darker to match the mud and sediment of the water.
Another big distinguishing factor between crocodiles and alligators is their size.
Saltwater crocodiles are the largest of the bunch.
They can grow to be up to 23 feet in length.
American crocodiles are a little smaller.
They tend to grow as long as 20 feet, but their average growth ranges from 14 feet to 17 feet.
Their average weight ranges from 800 to 1,000 pounds.
American alligators aren’t quite as long.
They tend to grow up to 13 feet in length, but the average is 12 feet.
Depending on the sex, they can weigh as much as 1,000 pounds like the crocodile.
Female alligators tend to weigh a little less than their male counterparts.
Their average weight is 500 to 700 pounds.
One reason crocodiles may be a little bigger than alligators is their environment.
Since they tend to live in saltwater, they have a lot of space in which to grow.
Alligators don’t have as much space.
They prefer to live in swamps and lakes which restricts their growth and diet.
Telling the difference between the two based on size isn’t easy.
Both tend to stay in the water which can make seeing their whole size difficult.
Unless you have them side-by-side, it’s also difficult to tell the difference between their sizes.
While the two are distinguishable because of their relative size, this method isn’t the easiest to apply when in the field.
3. Snout Shape
Perhaps the easiest way to tell the difference between an alligator and a crocodile is the shape of its snout.
Since alligators and crocodiles need to breathe, you can usually find their heads above the water even if the rest of their bodies aren’t.
That makes determining its snout shape a lot more reliable in terms of identifying it than trying to measure its body’s length.
An alligator has a U-shaped snout.
It’s very broad and flat at its tip.
It also has a different jaw.
The alligator closes its mouth in a downward direction.
As a result, its bottom teeth fit over the top of its mouth.
This obscures its bottom row of teeth in the process.
The crocodile is the opposite in almost every aspect.
Its snout has a V-shape.
Even though crocodiles have varying lengths of snouts, they always end in a point.
Their jaws are also different from an alligator’s.
They have an overbite rather than an underbite.
Because of this, their top teeth tend to fit over their bottom.
However, you can still see both sets of teeth.
If you were to examine a crocodile closely enough, you’d be able to see five bottom teeth when it has its mouth closed.
When trying to discern the difference between the two, the shape of the snout is one of the easiest and most reliable methods to do so.
4. Bite Strength
Although you don’t want to try this out for yourself, the bite strengths between the two are also different.
A crocodile has the greatest bite strength at 3,700 psi.
Its teeth are also sharper than an alligator’s.
That’s because a crocodile bites down on its prey, then uses its teeth to tear it to pieces.
An alligator has rounded teeth.
They use their jaws and teeth for crushing their prey to death instead.
Because they rely on pressure to kill their prey, you might think that they have superior bite strength, but that isn’t the case.
Alligators have a bite strength of about 25,000 psi.
Crocodiles may have a stronger bite because they’re larger.
Since they’re larger, their jaw has larger and more powerful muscles than an alligator’s.
This allows them to apply more pressure when tearing their prey.
It might also have to do with the shape of their jaw.
Since crocodiles bite upwards, they need to use more power and strength to overcome gravity.
The result is a powerful bite that’s greater than an alligator’s.
Both crocodiles and alligators have dome pressure receptors on their body.
These receptors help them regulate water pressure.
This improves their swimming.
It also helps them detect any ripples in the water.
It can help them locate potential prey without having to break the surface or move much.
Considering that many alligators and crocodiles live in murkier areas, being able to rely on touch and sensation can make them better hunters.
The key difference in their dome pressure receptors is their locations and visibility.
Alligators have their dome pressure receptors on their mouths.
You can physically see them because they’re small black dots.
Crocodiles have them on their mouths, too, but they also have them all over their bodies.
This makes them better swimmers than alligators which is likely why they live in larger bodies of water.
They’re able to move more effortlessly through it.
Also unlike the alligator, their dome pressure receptors are translucent.
If you were to approach a crocodile or examine its corpse, then you may be able to pick out its receptors.
However, from a distance or while moving, it’s difficult to see their dome pressure receptors since they blend in with the rest of their scales.
The locations where the alligators and crocodiles live are also different.
That’s because both have different tolerances for colder temperatures.
Both are cold-blooded which means they require warmer temperatures in which to survive.
When the temperature drops below their preferred temperature, they fall into hibernation like a bear.
The difference between the two is that the alligator can live in colder temperatures than the crocodile.
They’re able to live in climates that drop down to 79 degrees Fahrenheit.
The crocodile, on the other hand, needs to live in areas between 85 and 93 degrees Fahrenheit.
Since alligators have greater resistance towards colder climates, you can sometimes find them as far north as North Carolina.
Alligators may migrate during the year, too, to stay within their optimal temperatures.
Others will simply go dormant and awaken when the temperature rises again.
Crocodiles tend to stay in the south.
They’re mostly at the southernmost tip of Florida and throughout hotter climates in South America and the Middle East.
This also explains their preferred habitats.
Since alligators are able to resist colder temperatures, they can travel further inland than crocodiles in the United States.
Since most bodies of water inland are either rivers or lakes, the alligators make their homes in them.
Southern Florida has a lot of swampland, streams, and easy access to the ocean.
Since this is where it’s the warmest, crocodiles prefer to make this area their home.
Their ability to live in saltwater also makes this area ideal for them.
7. Crocodiles Are Older Than Alligators
By examining the fossil record as it stands today, modern crocodiles are older than alligators.
Their ancestry takes them back to the Sarcosuchus.
It lived 110 million years ago and was the first crocodile ancestor to live on the land as well as in the water.
It could also grow to 40 feet long.
Their ancestry doesn’t stop there, however.
Before Sarcosuchus started to walk the land, they were predators of the water.
Their ancestry traces back to Thalattosuchia.
That species lived 200 million years ago.
Modern crocodiles emerged 70 million years ago which is still quite a feat.
Alligators are close to crocodiles in ancestry, but they don’t go quite as far back.
Many make the mistake of thinking that alligators and crocodiles are the same things, but they’re actually two different species.
This means that they’re unable to reproduce with each other and breed offspring.
Where the crocodile came from Sarcosuchus, alligators came from Deinosuchus.
That species dates to the Cretaceous period and not the Jurassic period.
In terms of the fossil record, the Cretaceous period came after the Jurassic period.
As a result, crocodiles are older than alligators.
8. Fewer Alligator Species
When breaking up crocodiles and alligators into their specific groups, things can be a little difficult.
Both crocodiles and alligators exist in the scientific group called an Order.
Their Order is Crocodilia.
Along with crocodiles and alligators, caimans and gharials are also a part of the Order Crocodilia.
Despite being in the same Order, crocodiles and alligators have different Family names.
The alligator’s family is Alligatoridae.
The family includes two different species of alligators as well as five caiman species.
The crocodile’s family is Crocodylidae.
The family includes 13 different crocodile species.
Those species live in various parts of the world like:
- United States
- Southeast Asia
Clearly, the alligator has a smaller number of species than the crocodile.
That may be because the crocodile is older than the alligator.
It’s had a longer span of time in which to branch off and create new species.
A final area in which crocodiles and alligators are different is in their temperament.
Crocodiles tend to be more aggressive than alligators.
Their aggression also differs based on the species of crocodile.
The most aggressive crocodiles are those that live in Australia and in the Nile River.
Most attacks, made by the Saltie crocodile, happen in Australia, but the Nile Crocodile is often just as aggressive.
There are hundreds of reported crocodile attacks made every year.
Amid those reports, alligators make up less than six percent.
That’s because alligators tend to be shy of humans.
They prefer to run or hide when encountering a human.
Alligators are usually aggressive when they’re defending their young or their eggs.
American crocodiles are also different from their counterparts in Australia and the Nile.
They also tend to be shy of humans.
While they’re more likely to attack than alligators, they’re still not as aggressive as other types of crocodiles.
Overall, however, crocodiles are more aggressive than alligators.
What Are The Similarities Between The Alligator And The Crocodile?
While there are major differences between alligators and crocodiles, there are also a few key similarities.
Here are some similarities between the alligator and the crocodile.
1. They’re Both Reptiles
Both species fall under the reptile classification of animals.
This means that they’re cold-blooded.
They’re unable to generate heat or regulate their own internal body temperature.
As a result, they have to find warmth elsewhere.
That’s why you’ll often find alligators and crocodiles laying out on rocks or in the sun.
It’s also why they have to live in warmer climates.
They can’t survive in colder climates since they’re unable to generate heat themselves.
One benefit that reptiles receive in return for not being able to regulate their body’s temperature is that they need less food.
While it may seem like alligators and crocodiles are always on the hunt, that isn’t the case.
They need to eat far less than mammals.
They also don’t use a lot of energy.
That also decreases their need for food.
Another similarity between them is where they live.
Both crocodiles and alligators prefer to live in or near the water.
That’s because they’re both extremely fast and agile swimmers.
While the specific types of water in which they live are different, you can find both in wetlands, rivers, and lakes.
Since they both live in the water, they also share a similar marine diet.
You can find both alligators and crocodiles eating mollusks and fish.
Speaking of their diet, they also share similarities in their other types of food.
Both baby crocodiles and alligators prefer to eat insects when they’re small.
They’ll also feed on small fish and crustaceans as they grow.
Once they’re larger, they start to eat larger animals.
Both crocodiles and alligators prefer to kill and eat their prey in two bites.
They have to exert more energy to drag larger animals into the water to drown them.
Since they don’t always want to do that and waste the energy, they often focus on hunting for smaller animals.
Both crocodiles and alligators have been around since the dinosaurs walked the earth.
In many instances, they’re practically modern-day dinosaurs in themselves.
Despite this shared history, they’re both significantly different from one another.
By understanding the differences we’ve discussed here, you can make distinguishing between the two a lot easier.