how many species of extant mammals are there today?
prototheria and theria
what are the two subclasses of mammalia
-egg laying mammals -mammary glands but no nipple or teat -males have abdominal (undescended) testes -multiple sex chromosomes -mechanoreceptors & electroreceptors on rostrum the detect prey -cloaca (monotreme means 1 hole) -teeth are absent -lower jaw and juggle reduced
describe characteristics of the order Monotremata
Trachyglossidae and Ornithorhynchidae
what two families are in the order monotremata?
echidna or spiny aneater are in what family?
duck billed platypus are in what family?
what is the marsupial infraclass?
how many mammals are rodents
skin glands, hair, air moving into lungs through negative pressure created by diaphragm and expansion of intercostal muscles around ribs, bear live young, single lower jaw bone (dentary),
Name characteristics that are unique to mammals
(T/F) Cuticle scale patterns and medulla pigment distinct among species
mammals maintain stable body temp through metabolic activity, fat storage, brown adipose tissue, behaviors (shivering, huddling, nesting)