Biologists have long debated about whether egg production in birds is biologically highly costly, some theorizing that egg produ

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问题     Biologists have long debated about whether egg production in birds is biologically highly costly, some theorizing that egg production is energetically or nutritionally demanding. Lack, however, suggested that clutch size—the number of eggs a bird lays per breeding cycle—is far below the potential limit of egg production. He suggested that clutch size had instead evolved in relation to the number of young that the parents could successfully rear. Subsequently, most studies focused on limitations operating during chick rearing, particularly among altricial species (species in which the parents feed their young in the nest). Lack later recognized that in precocial species (species in which young feed themselves), clutch size might be explained by different factors—the availability of food for egg-laying females, for example.
The passage suggests that Lack would agree with which of the following statements about factors affecting clutch size in birds?
Consider each of the choices separately and select all that apply.

选项 A、In altricial species, clutch size is determined primarily by factors operating after eggs are laid.
B、In precocial species, clutch size is determined primarily by factors operating after eggs are laid.
C、In many bird species, clutch size generally remains well below the potential limit of egg production.

答案A,C

解析 很多考生看到选项A时会纠结第四句究竟是不是拉克说的。实际上,选项A用第三句就能判断对错。第三句中,拉克认为“能养活多少就生多少”,而根据晚成型鸟类的定义,幼雏需要父母“养活”,因此晚成型鸟类的巢穴大小当然取决于产蛋之后的因素,即“养活能力”,因此选项A正确。C项同义改写第二句。B项根据第五句,早熟型鸟类取决于生蛋过程中雌鸟的营养,选项B错误。
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