Mammalogy

In zoology, mammalogy is the study of mammals – a class of vertebrates with characteristics such as homeothermic metabolism, fur, four-chambered hearts, and complex nervous systems. Mammalogy has also been known as “mastology,” “theriology,” and “therology.”Mammalogy branches off into other taxonomically-oriented disciplines such as primatology (study of primates), and cetology (study of cetaceans). There are many more.Mammals (formally Mammalia) are a class of vertebrate animals whose name is derived from their distinctive feature, mammary glands, which they use in feeding their young. They are also characterized by the possession of sweat glands, hair, three middle ear bones used in hearing, and a neocortex region in the brain.Except for the five species of monotremes (which lay eggs), all mammals give birth to live young. Most mammals also possess specialized teeth, and the largest group of mammals, the placentals, use a placenta during gestation. The mammalian brain regulates endothermic and circulatory systems, including a four-chambered heart.There are approximately 5,400 species of mammals, ranging in size from the 30–40-millimetre (1.2–1.6 in) Bumblebee Bat to the 33-metre (110 ft) Blue Whale, distributed in about 1,200 genera, 153 families, and 29 orders, though this varies by classification scheme.The mammals are divided into two subclasses, the prototheria, which includes the egg-laying monotremes, and the theria, which includes the live-bearing marsupials and placentals. Most mammals, including the six largest orders, belong to the placental group. The three largest orders, in descending order, are Rodentia (mice, rats, and other small, gnawing mammals), Chiroptera (bats), and Soricomorpha (shrews, moles and solenodons). The next three largest orders include the Carnivora (dogs, cats, weasels, bears, seals, and their relatives), the Cetartiodactyla (including the even-toed hoofed mammals and the whales) and the Primates to which the human species belongs. The relative size of these latter three orders differs according to the classification scheme and definitions used by various authors.Phylogenetically, Mammalia is defined as all descendants of the most recent common ancestor of monotremes (e.g., echidnas and platypuses) and therian mammals (marsupials and placentals). This means that some extinct groups of “mammals” are not members of the crown group Mammalia, even though most of them have all the characteristics that traditionally would have classified them as mammals. These “mammals” are now usually placed in the unranked clade Mammaliaformes.

The mammalian line of descent diverged from the sauropsid line at the end of the Carboniferous period. The sauropsids would evolve into modern-day reptiles and birds, while the synapsid branch led to mammals. The first true mammals appeared in the Jurassic period. Modern mammalian orders appeared in the Palaeocene and Eocene epochs of the Palaeogene period.

 

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Class Presentations

2008 – 2009 Class – Mammalogy, Dr. John YOung, TPWD

• Download the Mammals of Texas PDF file
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Feral Hog Control, by Mike Mitchell
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The damage Feral Hogs can do to native habitats:

Feral hogs negative affects, by Texas AgriLife