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America’s Next. TOP MAMMAL. 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
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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?