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This informative overview delves into the diverse orders of mammals found in America, examining their unique characteristics and feeding habits. From the constantly growing incisors of herbivorous rodents to the hoofed quadrupeds and powerful flying mammals, each group showcases distinct adaptations. We analyze eight key orders, highlighting features such as dentition, feeding strategies, locomotion, and size diversity. Understanding these traits can reveal the ecological roles and evolutionary pathways of these captivating mammals in their respective habitats.
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America’s Next TOP MAMMAL
Orders- Group 1: • One pair of constantly growing front teeth or incisors, kept short only by gnawing. • Incisors chisel shaped • Behind the incisors is a large gap in the tooth rows. There are no caninesTypically there are only a few molars at the rear of the jaws • Mainly herbivorous, though most are opportunistic ominivores/carnivores
Orders- Group 2: • Hoofed quadrupeds (four legs) • Most use the tips of their toes to sustain their whole body weight while moving • Two or four (usually) hoofed toes on each foot • Rasping cheek teeth, no upper incisors, two or four hoofed toes on each foot, complex stomach, and horns or antlers in most species
Orders- Group 3: • unique in that they have true powered flight • as a group are crepuscular or nocturnal • eyes are small and inefficient, but their ears are usually well developed • high-frequency vocals
Orders – Group 4: • Largest order of marsupials in the Western Hemisphere • Most have long snouts, a narrow braincase, and a prominent sagittal crest • Plantigrade stance (feet flat on the ground) and the hind feet have an opposable digit with no claw • Have prehensile (grasping) tails.
Orders- Group 5: • Enlarged fourth upperpremolarand first lower molar, which together form an efficient shear for cutting meat and tendon. Referred to as carnassialteeth. Incisors, if present modified for cutting/slicing. • most have relatively large brains. • All members simple stomachs • Many carnivore species are sexually dimorphic in size. Usually males are larger than females. Males often show ornamentation of some sort to attract females.
Orders- Group 6: • Have a rudimentary or short tail • Folds of skin on the lips can meet behind the incisors (front teeth) so that gnawing can take place with the mouth cavity closed • Other flaps of skin are able to close the nostrils • Large incisors grow throughout the animal's life. Canines are absent and a large space ( diastema) separates the incisors and the first cheek tooth. • They are almost strictly herbivorous
Orders- Group 7: • small to medium sized • pentadactyl (5 toed) • plantigrade(flat footed, stanced) • long pointed snouts • sharp teeth • pinnae and eyes are usually small to absent • Formerly known as Order Insectivora , named at the time for their niche and diet.
We are focusing on 7 orders of mammals in this unit. • What characteristics did all your animals have in common? List at least 4. Try to avoid overly general observations that would be common to all animals. • What seem to be the key characters that separated your orders? • Which orders do you think might be the most diverse-most types of species? Keep in mind, the photos only represent a sampling of organisms from each order. Why do you think this is? • Which orders do you think are the smallest in numbers? Why? • Which order do you think show the most variation in body form? Why do you think this group varies while others remained highly conserved?
