首页
登录
职称英语
The cycle of fluctuation in snowshoe hare populations is unusual among anima
The cycle of fluctuation in snowshoe hare populations is unusual among anima
游客
2024-01-10
68
管理
问题
The cycle of fluctuation in snowshoe hare populations is unusual among animal species in that it is remarkably regular—peaking every eight to eleven years—and broadly synchronized over a vast area. Declines from peak levels are initiated by markedly lower overwinter survival of young hares, sharp decreases in birth rates, and a declining survival rate for adult hares. The onset of population increases is brought about by greatly improved rates of survival and birth.
Some biologists hypothesize that the cycle begins when peak snowshoe hare populations exceed their winter food supply; resulting malnutrition triggers a population decline. As hare numbers fall, the ratio of predators to hares increases, as does the impact of predation on the hare population. This extends the decline beyond the period of winter food shortage. Hare scarcity then causes predator population declines, and with fewer predators and more abundant winter food, the hare population begins another cyclic increase. The high mobility of predators responding to local differences in hare abundance contributes to interregional synchrony. [br] The passage suggests that which of the following is true of fluctuations in snowshoe hare populations?
选项
A、Changes in hare population levels are not highly correlated with changes in predator population levels.
B、Hare populations in one region are unlikely to peak at the same time that populations in nearby regions are at the lowest point of the cycle.
C、The regularity of hare population fluctuations is greater in regions where populations peak every eight years than in regions where they peak every eleven years.
D、In areas where hare population cycles are greater than eleven years, predator mobility is unusually high.
E、Fluctuations in hare populations vary greatly from region to region, depending on available winter food supply.
答案
B
解析
一个区域在最下面,这个区域就不可能在最上面,这就是区域间的同步,选项B正确。
转载请注明原文地址:https://tihaiku.com/zcyy/3349359.html
相关试题推荐
Thestudy’swarningthatmonkeypopulationsweredeclininginGuatemalaandMexi
Manyoftheunusualbehaviorsattributedtocrows—suchasdrinkingcoffeeorpre
Recentlyanunusuallyhighnumberofdolphinshavebeenfounddeadofinfectious
Untilthecurrentwarmingtrendexceedstherangeofnormalclimaticfluctuation
Computerprogramsareunusualinthattheyarevirtuallytheonlyproductst
Haveyoueverexperiencedunusualweatherinyourcity? No,notthatIremember
ThechartsbelowgiveinformationontheagesofthepopulationsofYemenan
ThechartsbelowgiveinformationontheagesofthepopulationsofYemenan
TheFertilityBustAFattingpopulations—thedespair
TheFertilityBustAFattingpopulations—thedespair
随机试题
Weconsider______heshouldhaveleftwithouttellinganyonebeforehand.A、stran
Duringthe1980s,unemployment(失业人数)andunderemployment(不充分就业)insomecountr
Tensofthousandsofthepoorestpart-timestudentsaretogetextramoneyt
拌制混凝土时,砂的颗粒级配与粗细程度应同时考虑。
下列有关随机测量误差的表述,正确的是()。A.随机测量误差的参考量值是对同一被
组成中含有四物汤的方剂为A.泰山磐石散B.归脾汤C.逍遥散D.百合固金汤E.以上
建设工程质量事故的等级是以( )为标准划分的。 A、直接经济损失和人员伤亡数
人在每一瞬间,将心理活动选择了某些对象而忽略了另一些对象。这一特点指的是注意的(
银行承兑汇票的承兑银行,应当按照票面金额向出票人收取()的手续费。A:千分之一
(2021年第2批真题)建设用地使用权自()时设立。A.占用 B.登记
最新回复
(
0
)