1. Sunbear
   Aye-aye
2. Giant pangolin
   Echidna

Giant pangolins can grow to be over 70 pounds. They live in Africa and sustain themselves mostly on a diet of termites and ants. Pangolins are well suited to hunting termites because their size allows them to virtually destroy a termite mound just by leaning on it.

1. American alligator
   Green iguana
2. Monkey-tailed skink
   Gila monster

The American alligator was actually once on the endangered species list and it was feared they'd go extinct. Conservation efforts worked so well that the species is now thriving, with over a million animals in the wild.

1. Brown trout
   Yellowfin tuna
2. Arapaima fish
   Golden perch

The Arapaima fish shares waters with some dangerous predators like piranha. The scales of the Arapaima fish are so thick and arranged in intertwining layers that they're actually able to withstand the bite of a piranha.

1. Caiman
   Leopard gecko
2. Chameleon
   Chuckwalla

Chuckwallas are generally non-aggressive animals that flee from danger. In fact, if one feels threatened it may run to the nearest crevice in between some rocks and then quickly inflate its longs to expand into the space, making it difficult to pull out.

1. Green iguana
   Gila monster
2. Pit viper
   Texas horned lizard

Gila monsters are the largest lizards native to the United States and are generally kind of lazy creatures. Gila monsters rarely leave their dens, and when they do it's usually just to eat or sunbathe.

1. Ball python
   King cobra
2. Nile monitor
   Black mamba

Ball pythons are non-venomous and are the smallest of the python species. They're popular with people who like to have snakes as pets not just because of their manageable size, but because they tend to be pretty laid back as well.

1. Caiman
   Gold tegu
2. Rattlesnake
   King cobra

The scientific name for a sidewinder rattlesnake is crotalus cerastes. Crotalus comes from the Greek word for "castanet," a kind of hand-held percussion instrument.

1. Saltwater crocodile
   Komodo dragon
2. Green iguana
   Nile monitor

The massive saltwater crocodile can grow to lengths of around 20 feet. They also clock in at over 2,000 pounds, or one ton. The world record for largest saltwater crocodile in captivity was held by a croc named Lolong who was 2, 370 pounds.

1. Florida worm lizard
   Anaconda
2. King cobra
   Reticulated python

The king cobra is the largest venomous snake in the world, and when it's threatened, it produces a low-pitched hiss to warn off attackers. The king cobra's hiss is so low, in fact, it can often sound like a growl.

1. Guppy
   Betta
2. Angelfish
   Goldfish

Goldfish are members of the carp family that's actually native to Asia but is common all over the world now thanks to its popularity as an aquarium fish. In outdoor ponds, they're often used to help control mosquito populations.

1. Reticulated python
   Western cottonmouth
2. Garter snake
   Anaconda

The cottonmouth gets its name from its habit of opening its mouth to show off its fangs when trying to ward off predators. In stark contrast to its usually brown or black scales, the mouth is bright white and looks like cotton.

1. Black sea bass
   Catfish
2. Gold tegu
   Barracuda

Black sea bass can be fished all along the East Coast of the United States from Cape Cod to the Gulf of Mexico and are a favorite of anglers for being a good-sized fish that's also pretty tasty.

1. Nile monitor
   Reticulated python
2. Spitting cobra
   Green anaconda

Though not always the longest snakes in the world (even though they can grow to 30 feet), when it comes to mass the green anaconda is a behemoth. These snakes can reach weights of over 500 pounds!

1. Komodo dragon
   Bearded lizard
2. Texas horned lizard
   Green anole

It's been known for some time that the bite of a Komodo dragon is dangerous, not just for the obvious reasons. For a long time scientists believed the dragon just had toxic bacteria in its mouth, but it was later confirmed that Komodo dragons do produce venom.

1. Leopard gecko
   Jackson's chameleon
2. Caiman
   Green iguana

Caiman are closely related to alligators and crocodiles. For a time, when the American alligator was a protected species, people would import caiman from the Amazon to be sold in the United States.

1. Green iguana
   Five-lined skink
2. Rock lizard
   Black mamba

Green iguanas are found across South America and Mexico and usually can be found on rocks and in trees. There's a population on the island of Anguilla that showed up after being transported there by a pair of hurricanes in 1995.

1. Aardvark
   Platypus
2. Echidna
   Armadillo

Armadillos actually have a tough carapace that's made up of thousands of little scales called "scutes." Those scutes are made of keratin, which is the same stuff that makes up hair and fingernails.

1. Horned viper
   Gold tegu
2. Nile monitor
   Leopard gecko

When the temperature gets too low for a leopard gecko, it's forced underground. It won't go into hibernation exactly, rather something called brumation in which they still need to drink water but generally don't eat and may do little beyond sleep for months.

1. Bearded dragon
   Five-lined skink
2. Common wall lizard
   Barracuda

Bearded dragons are a pretty laid back species which makes it very suitable for keeping as pets. They also have a tendency to wave at each other in a show of species recognition or, in some cases, submission.

1. Giant tortoise
   Sea turtle
2. Black-knobbed map turtle
   Nile monitor

This unusual turtle gets its name from the series of spiky knobs that grow down the back of its shell that tend to make it look a bit like a living dinosaur.

1. Barracuda
   Brown trout
2. Sea bass
   Golden perch

Barracuda have a bit of a bit reputation among fish thanks to their aggressive nature. Barracuda have been known to attack divers for no reason whatsoever, and their sharp teeth can cause a lot of damage.

1. Green anole
   Brown basilisk
2. Jackson's chameleon
   Rock lizard

Even though chameleons have become popular pets over the years, species like the Jackson's Chameleon aren't very social animals. They are territorial and should be kept alone and they also don't really respond well to being handled.

1. Texas horned lizard
   Five-lined skink
2. Echidna
   Nile monitor

You'd think being covered in tiny spikes would be enough of a defense against predators, but the Texas horned lizard has an extra weird layer of defense as well. When confronted by a predator, it can squirt foul-tasting blood out of its eyes.

1. Five-lined skink
   Green anole
2. Gold tegu
   Secret toadhead agama

Green anoles have a flap of skin under their chin called a "dew-lap." The dew-lap is usually brightly colored and contrasts with the lizard's green scales. It's used to both attract a mate and to intimidate rivals.

1. Gold tegu
   Brown basilisk
2. Beaded lizard
   Chameleon

The brown basilisk can grow to be about two feet in length, though much of that will be tail. When startled, it can run away on its hind legs and is even able to run for short distances across the surface of still water.

1. Iguana
   Black mamba
2. Rock lizard
   Five-lined skink

The five-lined skink is one of only 7 lizard species native to Canada. While it used to be fairly common, in Ontario it's not considered an at-risk species with a population in decline.

1. Crested gecko
   Blue-tongue skink
2. Water dragon
   Giant tegu

The giant tegu is also known as the Argentine black and white tegu. They're said to be highly intelligent pets, and some owners claim you can even house train them like a dog.

1. Nile monitor
   Anaimalai spiny lizard
2. Secret toadhead agama
   Pit viper

Even though Nile monitors can grow to be around 7 feet long, they're still pretty agile. They can run faster than humans over short distances, and they're also pretty good at climbing trees.

1. Garter snake
   Florida worm lizard
2. Rattlesnake
   Asp

The Florida worm lizard doesn't have any limbs, which tend to make it look less like a lizard than most animals that bear the name. It also doesn't have external eyes. The eyes it does have are covered by scales and are mostly only useful in distinguishing light from dark.

1. Common garter snake
   Reticulated python
2. Cornsnake
   Kingsnake

The common garter snake definitely lives up to its name. Not the garter part, the common part. These snakes can be found from coast to coast and are the most widespread snake in North America.

1. Black rat snake
   Reticulated python
2. Death adder
   Bull snake

The venom of the death adder is an extremely potent neurotoxin that can cause muscle weakness and paralysis. If left untreated, the bite from a death adder could kill a human in about 6 hours.

1. Black mamba
   Royal python
2. Corn snake
   Milk snake

The black mamba has one of the deadliest reputations of any animal on Earth. The snakes are very fast, highly toxic and highly aggressive. Thousands of deaths have been attributed to black mambas over the years.

1. Caiman
   Red tegu
2. Common wall lizard
   Sharp-snouted rock lizard

Unlike many lizards, the sharp-snouted rock lizard s fairly tolerant of cold weather. In fact, it can sometimes be spotted out and about even when there is snow on the ground.

1. Common basilisk
   Anamalai spiny lizard
2. Common collared lizard
   Gold dust gecko

This native of India has a fairly limited range and is found mostly in the Anaimalai or Highwavys Mountains, which is where it gets its name.

1. Secret toadhead agama
   Crested gecko
2. Beaded lizard
   Glass lizard

The secret part of the secret toadhead agama's name comes from its very unusual method of trying to scare off would-be predators. The agama has large flaps of skin on either side of its mouth that it shows off when it hisses, making its mouth look massive.

1. Lava lizard
   Glass lizard
2. Mexican beaded lizard
   Red tegu

The Mexican beaded lizard, like the Gila monster, produces venom. Interestingly, the venom contains enzymes that are being studied for their potential benefits in treating health problems like diabetes.

1. Glass lizard
   Common wall lizard
2. Blue-tongued skink
   Plated lizard

The common wall lizard can be found through Italy and many other European countries, where true to its name, it likes to stick to walls and bask in the sun. A boy from Cincinnati brought some home from Italy in the 1950s and released them near his house. There's now a massive population in the area.

1. Horned viper
   Reticulated python
2. Kingsnake
   Milk snake

The horned viper's most noticeable features are the horns from which it gets its name. They're actually just large scales above each eye that help protect it from sand and also serve as camouflage.