-q9 to q12:the sloth bear an insect-eatinganimal

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Unformatted text preview: ------------------------------------------------------------------------------------------------------------Q9 to Q12:The sloth bear, an insect-eatinganimal native to Nepal, exhibits only onebehavior that is truly distinct from that ofLineother bear species: the females carry(5)their cubs (at least part-time) until thecubs are about nine months old, eventhough the cubs can walk on their ownat six months. Cub-carrying also occursamong some other myrmecophagous(10)(ant-eating) mammals; therefore, oneexplanation is that cub-carrying isnecessitated by myrmecophagy, sincemyrmecophagy entails a low metabolicrate and high energy expenditure in(15)walking between food patches. How-ever, although polar bears’ locomotionis similarly inefficient, polar bear cubswalk along with their mother. Further-more, the daily movements of sloth(20)bears and American black bears—which are similar in size to sloth bearsand have similar-sized home ranges—reveal similar travel rates and distances,suggesting that if black bear cubs are(25)able to keep up with their mother, sotoo should sloth bear cubs.An alternative explanation is defensefrom predation. Black bear cubs usetrees for defense, whereas brown bears(30)and polar bears, which regularly inhabittreeless environments, rely on aggres-sion to protect their cubs. Like brownbears and polar bears (and unlike othermyrmecophagous mammals, which are(35)noted for their passivity), sloth bearsare easily provoked to aggression.Sloth bears also have relatively largecanine teeth, which appear to be morefunctional for fighting than for foraging.(40)Like brown bears and polar bears,sloth bears may have evolved in anenvironment with few trees. They are17especially attracted to food-richgrasslands; although few grasslands(45)persist today on the Indian subcontinent,this type of habitat was once wide-spread there. Grasslands supporthigh densities of tigers, which fight andsometimes kill sloth bears; sloth bears(50)also coexist with and have been killedby tree-climbing leopards, and are oftenconfronted and chased by rhinocerosesand elephants, which can topple trees.Collectively these factors probably(55)selected against tree-climbing as adefensive strategy for sloth bear cubs.Because sloth bears are smaller thanbrown and polar bears and are undergreater threat from dangerous animals,(60)they may have adopted the extra pre-caution of carrying their cubs. Althoughcub-carrying may also be adoptive formyrmecophagous foraging, the behaviorof sloth bear cubs, which climb on their(65)mother’s back at the first sign of danger,suggests that predation was a keystimulus.--------------------------------------------------------------------------------Q9:The primary purpose of the passage is toA. trace the development of a particular behavioral characteristic of the sloth bearB. explore possible explanations for a particular behavioral characteristic of the sloth bearC. compare the defensive strategies of sloth bear cubs to the defensive strategies of cubs of other bear speciesD. describe how certain behavioral characteristics of the sloth bear differ from those D....
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-Q9 to Q12:The sloth bear an insect-eatinganimal native to...

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