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Reptiles & Fish
 Amphibians
 Canyon Treefrog
 Red-spotted Toad
 Fish
 Catfish
 Colorado Squawfish
 Humpback Chub
 Razorback Sucker
 Trout
 Lizards
 Collared Lizard
 Leopard Lizard
 Spiny Lizard
 Whiptail
 Snakes
 Coachwhip
 Gopher Snake
 Pygmy Rattlesnake
 Western Rattlesnake
Birds
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Mammals
  

 

  Reptiles & Fish

The creatures within this section are one of 4 basic types:

Amphibians
Fish
Lizards
Snakes

They are defined as follows:

Amphibians

Amphibians are a group of vertebrate animals that scientists believe were the first to emerge from water with an ability to live on land. They live on every continent except Antarctica. Amphibians include three groups: frogs and toads, salamanders, and caecilians. Most live part of their lives in water and part on land. They begin their lives as shell-less eggs that are laid in water. This prevents them from drying out. The eggs hatch into water dwelling larvae, also known as tadpoles or polliwogs. Through a process called metamorphosis, which can take a few weeks to several months, the larvae eventually become very different looking mature adults. Most amphibians are small (less than six inches in length), cold blooded, and have smooth, slimy, moist skin without external scales, hair, or feathers. The majority live in moist habitats, near ponds, streams, or lakes, and eat insects.

Most frogs and toads have four legs and no tails. Their limbs have digits (fingers) and their hind legs are long and used for leaping. They also have well-developed voices and good hearing. Salamanders have long tails and four short legs. Caecilians, which are only found in tropical regions, do not have legs and look like large earthworms. Amphibians are in the class Amphibia.

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Fish

Fish appeared during the Silurian period, about five hundred million years ago, and were the first vertebrate (backboned) animals on the earth. There are more than twenty-four thousand species of fish and they represent the largest and most diverse group of animals in the world. They live almost anywhere there is water, from the near freezing Arctic to equatorial tropical seas. Most never leave the water but a few species are able to survive for a few hours to several months on land. Fish are an extremely important part of the earth's food chain, which helps keep the ecosystem of our planet balanced. They also provide food, sports, and pets for people.

The two most common features of fish are their backbone and gills. Most also have fins and are cold-blooded. They usually have a streamlined body and a two chambered heart. Fish either have scales and a bony plate or they are scaleless. All fish are divided into two superclasses. One is Agnatha, or the jawless fish. The other is Pisces, or the jawed fish. The jawed fish are divided into two additional classes, Osteichthyes and Chondrichthyes. The Osteichthyes class is made up of bony fish. This is the largest group of fish in the world. The Chondrichthyes class is made up of cartilaginous fish.

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Lizards

There are many varieties of lizards throughout the world. Some are legless, some simulate flight and others are the size of crocodiles and can grow up to nine or ten feet in length. They all vary in color and size and habit. Most lay eggs, have moveable eyelids, and four limbs, the two hind limbs being larger than the two forelimbs. All have tails, small, sharp teeth, and a dry, tough outer skin of scales that periodically sheds (molts). Some have long, forked tongues and others have no tongues at all. Most are active and spend their time hunting, courting, mating, and defending their territory. Many lizards live in the deserts and are terrestrial. Some are tree dwelling and others are semiaquatic. There are two venomous species of lizards. Lizards belong to the order Squamata in the class Reptilia, which also includes snakes.

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Snakes

There are over 2,700 species of snakes. Scientists think that these legless reptiles were developed from lizards approximately 100 million years ago. Snakes are cold-blooded which means that their body temperatures are dependent upon the external environment. They can not survive in areas where the ground stays frozen all year. Although most are found in the tropics, snakes live almost everywhere on earth, in deserts, oceans, forests, streams, and lakes. Some live underground, many are ground dwellers, some live in trees, and others live in water.

Snakes range in size from four inches to over thirty feet in length. They may be stout or very slender. All are covered with dry scales and have two layers of skin. They occasionally shed (molt) the outer layer. Many are poisonous. Snakes have a clear scale covering each eye. They can see movement but their vision is good only for a short distance. They can pick up vibrations through the ground and also detect a limited range of sounds in the air through inner ears. Snakes have a keen sense of smell. They use their long, narrow, forked tongues, along with an organ called the Jacobson's organ and their nostrils, to detect odors. Some are also able to determine the location of nearby, warm-blooded animals by detecting small changes in temperature through special heat-sensitive pit organs located in their heads. A snake's upper and lower jaws move independently and are not hinged together. Neither are its ribs attached to its spine. Both of these features allow them to swallow outsized prey. Snakes cannot chew their food. Instead they eat their prey whole. Snakes are in the order Squamata.

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