Earth Science/Living

Creatures By: Brady Arnold

Table of Contents

1. Amphibians

2. Reptiles

3. Mammals

What is an Amphibian? •Amphibians

•Vertebrate animals (Animals with a spine)

•Toads •Frogs •Salamanders. •Characterized as cold-blooded.

•Most Amphibians transform from water-breathing young animals to adult air-breathing animals.

•The 3 orders of amphibians

•Frogs and toads •Salamanders and Newts •Limbless amphibians that resemble snakes

Amphibians Continued • Amphibians

– Approximately 6,500 species.

– Lay their eggs in water.

• Amphibians are similar to reptiles, but reptiles are amniotes (come from an egg), along with mammals and birds.

• There has been a dramatic decline in amphibians around the world. – Many species are threatened or extinct.

Different Kinds of Amphibians

What is a Reptile? •Reptiles

•Air-breathing •Cold-blooded vertebrates •Lay shelled eggs •Have skin covered in scales.

•They are Tetrapods

•Having four limbs or being descended from four-limbed ancestors.

•Modern reptiles inhabit every continent with the exception of Antarctica.

Reptiles Continued • Four reptile groups that are recognized

• Crocodillia: Crocodiles and alligators (23 species)

• Sphenodontia: Tuataras from New Zealand (2 species)

• Squamata: lizards, snakes, and worm lizards (9,150 species)

• Testudines: turtles, tortoises: (300+ species)

• Unlike amphibians, reptiles do not have an aquatic larval stage. • Reptiles are oviparous (egg-laying).

Different Kinds of Reptiles

What is a Mammal? •Air-breathing vertebrate animals

•Endothermic (Maintain own body heat)

•Hair

•Three middle ear bones

•Mammary glands (Exists in mothers with babies).

•Sweat glands

•Specialized teeth

•Most have a placenta (This feeds the offspring during pregnancy.)

•The mammalian brain regulates the endothermic and circulatory systems (the blood in the body)

•Circulatory System is operated with a four-chambered heart.

•Mammals range in size from the 1.5-inch Bumblebee Bat to the 108-foot Blue Whale.

Mammals Continued • All female mammals nurse their young with milk, which comes out

from special glands called mammary glands.

• All living mammals give birth to live young. • The 3 largest mammal groups are:

– Rodentia: (mice, rats, porcupines, beavers, capybaras, and other gnawing mammals)

– Chiroptera: (bats) – Soricomorpha: (shrews, and moles).

• The next 3 largest mammal groups are:

– Primates: (humans, Apes, Monkeys) – Cetartiodactyla: (hoofed mammals and whales) – Carnivora: (dogs, cats, weasels, bears, seals, and their relatives)

Pictures of Mammals