Stuart S. SumidaBiology 342

(Over) Simplified Phylogeny of Mammalia

Memorize this.

Just kidding.

Mon

otre

mat

a

Mar

supa

lia

Eden

tata

Rode

ntia

Lago

mor

pha

Prim

ates

Chiro

pter

a

Carn

ivor

a

Artio

dact

ylia

Cetc

acea

Peris

soda

ctyl

ia

Prob

osci

dea

Mon

otre

mat

a

Mar

supa

lia

Eden

tata

Rode

ntia

Lago

mor

pha

Prim

ates

Chiro

pter

a

Carn

ivor

a

Artio

dact

ylia

Cetc

acea

Peris

soda

ctyl

ia

Prob

osci

dea

Mammalia:•Mammary glands•Hair•Dentary-squamosal jaw-joint•Dentary – single bone of lower jaw•Three middle ear ossicles•Muscles of facial expression•Muscular diaphragm

MONOTREMATA: •Most basal of living mammals. •Retain primitive anmiote feature of laying eggs.•Includes only a few relict living forms including duckbilled platypus and spiny anteater.

Mon

otre

mat

a

Mar

supa

lia

Eden

tata

Rode

ntia

Lago

mor

pha

Prim

ates

Chiro

pter

a

Carn

ivor

a

Artio

dact

ylia

Cetc

acea

Peris

soda

ctyl

ia

Prob

osci

dea

Theria:•Mammals with internal development•Placenta

METATHERIA (Marsupalia):

•The pouch mammals•Choriovittiline (chorion + yolk sac) placenta•Living forms have epipubic bones (the primitive placentals probably did as well.)•Restricted primarily to Australi currently, though one form remains in North America (Didelphis; the Virginia oppossum).

Kangaroos can be almost orthograde

Mon

otre

mat

a

Mar

supa

lia

Eden

tata

Rode

ntia

Lago

mor

pha

Prim

ates

Chiro

pter

a

Carn

ivor

a

Artio

dact

ylia

Cetc

acea

Peris

soda

ctyl

ia

Prob

osci

dea

Eutheira:“True placental mammals”With extended internal developmentChorioallantoicplacenta

Mammalian Highlights / Features of Note:

•Primates are a very early offshoot within Mammalia.•The relationships of basal mammals are not terribly clear – as noted by the polychotomy between edentates, glires (rodents + lagomorphs), primates, and bats.•Cetaceans are actually most closely related to artiodactyls (pigs actually)!•Elephants and their kin are amongst the most derived of mammals

Many, many taxa are left out here.