|what are the adaptations for burrowing moles?||some have lost incisors and canine, and one premolar.|
rotated so that digits point to side, palms face backwards, and elbows pint upward.
phalanges: short, claws long.
clavicle and humerus short and robust.
manubrium of sternum greatly enlarged and extends forward to beneath base of skull.
|adaptations in burrowing moles|
|moves shoulder joint forward so that forepaws can loosen soil beside the snout. clavicle provides secondary articular surface with humerus.||adaptation for burrowing in moles|
|double articulation provides hinge-like movement and strong bracing for rotation of humerus that accompanies digging stroke.||adaptation for burrowing in mole|
|bat skulls and teeth are shaped by their||diet|
|bats that have alrge canines nd incisors for trapping and puncturing eat what?||large beetles|
|less specialized bat that eats moths and beetles||hoary bat|
|the upper fourth premolar and three molars. comparable lower teeth.||cheek teeth of insectivorous bat|
|second and third upper molars. comparable lower teeth||cheek teeth of nectarivorous bat|
|upper fourth premolar and three molars and the comparable lower teeth.||cheek teeth of frugivorous bat|
|the most successful mammals||rodentia|
|long middle branch from beneath front of zygomatic arch to back of jaw. deeper portion vertically directed between zygomatic arch and lower portion of jaw.||protogomorph|
|middle branch from front of orbit on side of face.||sciuromorph|
|deep branch from inside zygomatic arch and forward through infraorbital opening in fromt of eye.||hystricomorph|
|both forward. deeper portion through infraorbital foramen. middle portion in front of orbit.||myomorph|
|what are the specializations for herbivory in rodents?||teeth are rough grinding surface with long lasting molars, for breaking cell walls and grinding seeds.|
|high crowned with grinding surfaces complicated by folding of enamel||derived hypsodont|
|low crowned with blunt cusps||primitively bunodont|
|enamel ridges connect the cusps and expanded.||lophodont|
|two upper pairs of incisors, one lower pair. no specializations of masseter muscle. cheek teeth with ridged crowns for cutting.||lagomorpha, rabbits|
|changes in cetaceans from terrestial mammals:||forelimb now a steering device
tail now a horizontal caudal fin
|Porpoises, dolphins, sperm whales, baleen whales; 20 to 120,000kg; worldwide in oceans and in some rivers and lakes in Asia, South America, northern America, and Eurasia. Molecular data place whales within the order Artiodactyla.||Cetacea|
|bones of arm and hands (except thumb) are elongate and slender. distal portion of ulna reduced, so looks like single bone in lower limb.||chiroptera: bats|
|extends from body and hind limbs to arm and fifth finger, between the fingers, form hind limb to tail, and from arm to occipitopollicalis muscle||bat wing membrane|
|bat flying mechanism||airfoil as in bird wings|
|upstroke stopped by lock of enlarged greater tuberosity of humerus against the||scapula|
|muscles that bind scapula to axial skeleton ultimately responsible for stopping the||upstroke|
|anteaters, sloths, armadillos; 20g to 33kg; Neotropical region (plus some armadillos in southern United States of America)||xenarthra|