"Mammalia: Popcorn of the Cretaceous"

Mammalia is the scientific way of referring to mammals.

Kingdom = animalia
Phylum = chordata
class = mammalia

Modern mammals are divided into three sub-classes:

• Prototheria (Mammals that lay eggs, also known as monotremes)
• Metatheria (Marsupials, pouched mammals)
• And Eutheria (placental mammals.)

Class mammalia is a comparatively small group of furry vertebrata. They have mammary glands, hair, a four-chambered heart, a single lower jawbone, and they are endothermic. Most of them give birth to live young, but eutheria do not.

Domain Eucarya
Kingdom Animalia
Phylum Chordata
Subphylum Vertebrata
Class Mammalia

Mammals evolved on land during the late Triassic period, but were not nearly as successful as the dinosaurs which evolved at the same time.

During the Cenozoic Era, mammals radiated into so many ecological niches that the Era is often called the "Age of Mammals".

Defining mammalian characteristics include:

• Mammary glands from which females feed their newborn offspring
• Three bones in the middle ear
• Molar and premolar "cheek teeth" (where they have not evolved away)
• Bodies covered in hair

• Paleoryctoidae

• Subclass Prototheria:

  • Infraclass Eotheria:
    • Order Triconodonta (Triassic - Cretaceous, EXTINCT)
    • Order Docodonta (Jurassic, EXTINCT)
  • Infraclass Ornithodelphia:
    • Order Monotremata (platypus, echidna) (2, 3, 3) (Australia & New Guinea)
  • Infraclass Allotheria:
    • Order Multituberculata (Jurassic - Eocene, EXTINCT)

• Subclass Theria:

  • Infraclass Pantotheria:

    • Order Symmetrodonta (Jurassic - Cretaceous, EXTINCT)
    • Order Eupantotheria (Jurassic - Cretaceous, EXTINCT)

  • Infraclass Metatheria (marsupials):

    • Order Didelphimorphia (opossums) (1, ,60)(Americas)
    • Order Paucituberculata (1, 2, 5) (South America)
    • Order Microbiotheria (1, 1, 1) (monito del monte)(South America)
    • Order Dasyuromorphia aka Marsupicarnivora (3, 17 ,63) (numbat, thylacine) (Australia & Tasmania)
    • Order Peramelemorphia aka Peramelina (2, 8, 21) (bandicoot, bilbie)(Australia)
    • Order Notoryctemorphia (1, 1, 2) (marsupial mole)(Australia)
    • Order Diprotodontia (kangaroos, wallabies, wombats, etc.) (10, 39, 117) (Australia and New Guinea)

  • Infraclass Eutheria:

  • Order Proteutheria (Cretaceous - Oligocene, EXTINCT)
  • Order Pantodonta (Paleocene - Ologicene, EXTINCT)
  • Order Dinocerata (Paleocene - Eocene, EXTINCT)
  • Order Tillodontia (Paleocene- Eocene, EXTINCT)
  • Order Taeniodonta (Paleocene - Eocene, EXTINCT)
  • Order Hyaenodonta aka Creodonta (Cretaceous - Oligocene, EXTINCT)
  • Order Xenungulata (Paleocene, EXTINCT)
  • Order Pyrotheria (Eocene - Oligocene, EXTINCT)
  • Order Desmostylia (Miocene - Pliocene, EXTINCT)
  • Order Notungulata (Paleocene - Pleistocene, EXTINCT)
  • Order Astrapotheria (Paleocene - Miocene, EXTINCT)
  • Order Liptopterna (Paleocene - Pleistocene, EXTINCT)
  • Order Embrithopoda (Oligocene, EXTINCT)
  • Order Condylarthra (Cretaceous - Oligocene, EXTINCT)
  • Order Insectivora (hedgehogs, moles, shrews, tenrecs) (6, 65, 403)
  • Order Scandentia (tree shrews) (1, 5, 19)
  • Order Macroscelidea (elephant shrews]) (1, 4, 19)
  • Order Dermoptera (colugo aka flying lemur) (1, 1, 2)
  • Order Pholidota (pangolin) (1, 1, 7)
  • Order Chiroptera (bats) (17,,925)
  • Order Xenarthra aka Edentata (sloths, anteaters, armadilloes)
  • Order Lagomorpha (rabbits) (2, 13, 80)
  • Order Tubulidentata (aardvark) (1, 1, 1) (Africa)
  • Order Rodentia (rodents) (30, ,2000+) (includes Caviomorpha)
  • Order Carnivora(carnivores) (11, 167, 250) (subsumes Pinnipedia)
  • Order Proboscidea (elephants) (1, 2, 3) (Africa and South Asia)
  • Order Hyracoidea (hyraxes) (1, 3, 6)
  • Order Perissodactyla (horse, tapir, rhinoceros) (3, 5, 14)
  • Order Artiodactyla (even-toed ungulates: pig, deer, etc.)
  • Order Sirenia (manatee, dugong) (2, 3, 4)
  • Order Cetacea (dolphins and whales) (13, 40, 79), sometimes broken into
    • Order Archaeoceti (Eocene - Miocene, EXTINCT)
    • Order Mysticeti (Baleen Whales) (3, 7, 13)
    • Order Ondontoceti (Toothed Whales, dolphins) (3, 7, 13)
  • Order Primates (lemurs, monkeys, apes, humans) (13, 65, 233)

Mammals are a class of bony fishes that have evolved to live on land, and whose scales have attenuated into long, thin projections called "hair". A cladistic lineage of the mammals looks something like this¹:

Eukaryota - cells with nuclei
Ophisthokonta
Metazoa - animals
Bilateria - triploblast embryos, bodies with bilateral symmetry
Deuterostoma
Chordata - vertebrates
Craniata - vertebrates with skulls
Vertebrata - vertebrates with backbones (i.e. instead of a cartaliginous notochord
Gnathostomata - vertebrates with jaws
Teleostomi - mouth at end, three ear bones
Osteichthyes - bony fishes
Sarcopterygii - lobed fins
Tetrapoda - four limbs
Stegocephalia - digits
Amniota - young develop in amniotic egg
Synapsida - ear hole in skull
Anthracosauria
Eupleycosauria
Sphenacodontia
Sphenacodontoidea
Therapsida
Theriodontia
Cynodontia
Mammalia

University of Michigan Animal Diversity Web - Mammalia
http://animaldiversity.ummz.umich.edu/chordata/mammalia.html

Smithsonian Institution, National Museum of Natural History, MSW Scientific Names
http://www.nmnh.si.edu/cgi-bin/wdb/msw/names/query/1

The Ultimate Ungulate Page, your guide to the world's Hoofed Mammals]
http://www.ultimateungulate.com/index.html

Biognomen
http://members.aol.com/bafiler/index.html

¹Tree of Life Web Project
http://tolweb.org/tree/

MAMMALS: A World Listing of Living and Extinct Species, Edited by John H. Burkitt, Tennessee Department of Agriculture, Nashville, Tennessee, Second Edition, 1995

Mam*ma"li*a (?), n. pl. [NL., from L. mammalis. See Mammal.] Zool.

The highest class of Vertebrata. The young are nourished for a time by milk, or an analogous fluid, secreted by the mammary glands of the mother.

Mammalia are divided into threes subclasses; --

I. Placentalia. This subclass embraces all the higher orders, including man. In these the fetus is attached to the uterus by a placenta.

II. Marsupialia. In these no placenta is formed, and the young, which are born at an early state of development, are carried for a time attached to the teats, and usually protected by a marsupial pouch. The opossum, kangaroo, wombat, and koala are examples.

III. Monotremata. In this group, which includes the genera Echidna and Ornithorhynchus, the female lays large eggs resembling those of a bird or lizard, and the young, which are hatched like those of birds, are nourished by a watery secretion from the imperfectly developed mammae.

© Webster 1913.