Mammals come in all shapes and sizes, and can be found all over the earth and come in all shapes and sizes. There are around 5500 species of mammals in all. You are a mammal, all of your friends are mammals and so is your dog. All mammals are warm-blooded and have either hair or fur on their bodies. The majority of all mammals give birth to live young, but there are a few species of mammals that lay eggs. The Triassic period, 220 million years ago, was the age that the first mammals can be found. During the Triassic period, about 220 million years ago, the first Mammal species were roaming the Earth. These mammal ancestors were preceded by a group called the 'synapsids'. There were three distinct groups of creatures prior to the Triassic period, of which 'synapsid' is one. The others are 'diapsids' and 'anapsids'. The terminology makes reference to the holes on their skulls where the jaw muscles attach. 'Synapsids' (mammals) have one hole on either side, 'diapsids' (dinosaurs, reptiles, birds) have two holes on either side, and 'anapsids' (turtles) have none.
Mammal Classification list
- Subclass/Order Monotremata: egg-laying mammals
- Order Monotremata: echidnas and platypus
- Subclass Marsupialia: marsupials
- Order Didelphimorphia: New World opossums
- Order Paucituberculata: shrew opossums
- Order Microbiotheria: Monito del Monte
- Order Dasyuromorphia: marsupial carnivores
- Order Notoryctemorphia: marsupial mole
- Order Peramelemorphia: bandicoots and bilbies
- Order Diprotodontia: koalas, wombats, kangaroos
- Subclass Placentalia
- Order Xenarthra: sloths, anteaters, armadillos
- Superorder Glires
- Order Rodentia: rodents
- Order Lagomorpha: rabbits, hares
- Superorder Euarchonta:
- Order Primates: primates
- Order Scandentia: treeshrews
- Order Dermoptera: colugos
- Order Insectivora: shrews, tenrecs, moles
- Order Chiroptera: bats
- Order Carnivora: dogs, cats, weasels, seals
- Order Pholidota: pangolins
- Superorder Ungulata: ungulates
- Order Tubulidentata: aardvark
- Order Macroscelidea: elephant shrews
- Order Hyracoidea: hyraxes
- Order Proboscidea: elephants
- Order Sirenia: manatees, dugong
- Order Perissodactyla: horses, rhinos
- Order Artiodactyla: even-toed ungul
- Order Cetacea: whales
From Learn Animals! http://www.learnanimals.com/mammals.php
