Mammals

|  | Orders of Mammals

Infraclass  | Superorder  | Order  | Common Representatives
Eutheria | Afrotheria | Afrosoricida | golden moles
Eutheria | Afrotheria | Hyracoidea | hyraxes
Eutheria | Afrotheria | Macroscelidea | elephant shrews
Eutheria | Afrotheria | Sirenia | manatees
Eutheria | Afrotheria | Proboscidea | elephants
Eutheria | Afrotheria | Tubulidentata | aardvarks
|  |  |
Eutheria | Euarchontoglires | Dermoptera | flying lemurs
Eutheria | Euarchontoglires | Lagomorpha | rabbits
Eutheria | Euarchontoglires | Primates | chimps
Eutheria | Euarchontoglires | Rodentia | mice
Eutheria | Euarchontoglires | Scandentia | tree shrews
|  |  |
Eutheria | Laurasiatheria | Artiodactyla | pigs, goats, sheep, cows
Eutheria | Laurasiatheria | Carnivora | cats and dogs
Eutheria | Laurasiatheria | Cetacea | whales and dolphins
Eutheria | Laurasiatheria | Chiroptera | bats
Eutheria | Laurasiatheria | Erinaceomorpha | hedgehogs
Eutheria | Laurasiatheria | Perissodactyla | horses
Eutheria | Laurasiatheria | Pholidota | scaly anteaters
Eutheria | Laurasiatheria | Soricomorpha | white-toothed shrews
|  |  |
Eutheria | Xenarthra | Cingulata | armadillos
Eutheria | Xenarthra | Pilosa | giant anteaters
|  |  |
|  |  |
Marsupial | Ameridelphia | Didelphimorphia | Virginia opossums
Marsupial | Ameridelphia | Paucituberculata | shrew opossums
|  |  |
Marsupial | Australidelphia | Dasyuromorphia | Tasmanian devils
Marsupial | Australidelphia | Diprotodontia | kangaroos
Marsupial | Australidelphia | Microbiotheria | monito del monte
Marsupial | Australidelphia | Notoryctemorphia | marsupial moles
Marsupial | Australidelphia | Peramelemorphia | marsupial omnivores

Mammals are a class of tetrapods that include camels, chimpanzees, cats and rats and elephants, goats and sheep, horses and cows. [1] The class of mammals can be divided into two main infraclasses: eutheria and the marsupials.

EUTHERIA = the crown placental mammals

Eutheria (Greek: "true beasts") is a group of mammals consisting of the first placental mammal and all of her decendants. The earliest known fossil eutherian, Eomaia, was found in Asia, and is dated to the Early Cretaceous period, about 125 million years ago. [2] Most placental mammals belong to one of four main superorders: Afrotheria, Euarchontoglires, Laurasiatheria, and Xenarthra.

| Eutheria

|  | Boreoeutheria

|  |  |

Euarchontoglires

|

Laurasiatheria

Atlantogenata

|  |  |

Xenarthra

|

Afrotheria

Euarchontoglires + Laurasiatheria = Boreoeutheria

and

Xenarthra + Afrotheria = Atlantogenata.

Xenarthra diverged from Afrotheria relatively rapidly after Atlantogenata diverged from Boreoeutheria. There was considerable gene flow among the nascent clades prior to their divergence. This made it difficult to resolve the above phylogenic tree until relatively recently. [3]

MARSUPIALS

The seven living orders of marsupials are divided into two clades: Ameridelphia and Australidelphia. [4]

MONOTREMATA

| mammals

|  | Theria

|  |  |

Eutheria

|

Marsupials

|  |  |

Monotremata

|

Order monotremata = Subclass prototheria

Eutheria + Marsupials = Subclass theria

## References

[edit | edit source]

1. ↑ http://species.wikimedia.org/wiki/Mammalia
2. ↑ http://en.wikipedia.org/wiki/Eutheria
3. ↑ http://mbe.oxfordjournals.org/content/24/9/2059.short
4. ↑ http://www.ncbi.nlm.nih.gov/pubmed/12878458