The energetics of reproduction in endotherms and its implication for their conservation.
The energetics of reproduction in endotherms and its implication for their conservation.
复制标题
吸热繁殖的能量学及其对其保护的意义。
DOI：
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发表时间：
2006
影响因子：
2.6
通讯作者：
B. McNab
中科院分区：
文献类型：
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作者：
B. McNab
恒温动物的能量消耗，通过其对繁殖速度的影响，影响了它们承受竞争、忍受环境干扰和忍受捕食的能力。哺乳类动物的繁殖力随着代谢速率的增加而增加，因为出生后生长速率增加，妊娠期和从怀孕到断奶期随着基础代谢速率的增加而减少。这些相关性解释了种群波动大的物种具有高代谢率和繁殖率的观察结果。高代谢率的物种在利用允许消费者有高代谢率的资源时胜过低代谢率的物种，这解释了为什么真食肉动物取代有袋食肉动物，因为它们的繁殖形式都没有高的基础代谢率。鸟类的繁殖力似乎也与能量消耗有关，这可能是人类入侵后海洋岛屿特有鸟类大量死亡的原因：岛屿特有鸟类，其中许多代谢率低，无法增加繁殖力，以应对人类造成的死亡率增加。为了长期保护以低能量消耗率为特征的恒温动物，需要将它们与高水平的捕食和竞争隔离开来，这种情况可能只发生在没有恒温动物捕食者和物种多样性低的岛屿上。这些恒温动物如果在生态上与一般动物群隔离开来，就可以在大陆上生存。
The energy expenditure of endotherms, through its impact on the rate of reproduction, affects their ability to withstand competition, to tolerate environmental disturbances, and to endure predation. The fecundity of eutherian mammals increases with rate of metabolism because the post-natal growth rate increases and the gestation and conception-to-weaning periods decrease with a mass-independent increase in basal rate of metabolism. These correlations account for the observation that species that have large population fluctuations have high rates of metabolism and reproduction. Species with high rates of metabolism out-compete species with low rates when using resources that permit consumers to have high rates of metabolism, which explains why eutherian carnivores replace marsupial carnivores, none of which have high basal rates as a result of their form of reproduction. Fecundity in birds also appears to correlate with energy expenditure, which may account for the huge die-off of birds endemic to oceanic islands after the invasion of humans: island endemics, many of which have low rates of metabolism, are unable to increase fecundity in response to a human-based increase in mortality. The long-term protection for endotherms characterized by low rates of energy expenditure requires their isolation from high levels of predation and competition, conditions that are likely to occur only on islands free from eutherian predators and with low species diversity. Such endotherms may survive on continents if they are ecologically isolated from the general fauna.