| A | B |
|---|
| monotremes | mammals that lay eggs |
| marsupials | pouched mammals |
| placental mammals | mammals whose embryos are protected by a placenta |
| mammals | endothermic vertebrates that nurse their young from mammary glands |
| Insectivora | moles' and hedgehogs' order |
| Chiroptera | bats' order |
| Edentata | sloths' and armadillos' order |
| Rodentia | mice's, rats', and beavers' order |
| Lagomorpha | rabbits' and hares' order |
| Carnivora | dogs', cats', bears', and seals' order |
| Cetacea | whales' and dolphins' order |
| Sirenia | order containing manatees |
| Artiodactyla | order containing even-toed animals, such as cows |
| Perissodactyla | order of odd-toed animals, such as horses |
| Proboscidea | order containing elephants |
| Primates | order containing apes, monkeys, and us |
| prehensile tail | tail used by New World monkeys for climbing |
| rumen | chamber in an herbivore's digestive tract that breaks down cellulose |
| cecum | cellulose-digesting pouch that devolved into the appendix |
| placenta | organ in placental mammals |
