Linking demographic responses and life history tactics from longitudinal data in mammals
Linking demographic responses and life history tactics from longitudinal data in mammals
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DOI：
10.1111/oik.02582
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发表时间：
2016-03-01
期刊：
影响因子：
3.4
通讯作者：
Baubet, Eric
中科院分区：
文献类型：
--
作者：
Gamelon, Marlene;Gaillard, Jean-Michel;Baubet, Eric
在随机环境中，人口参数的变化可以直接或通过对年龄结构的影响来影响人口增长率。长期随机增长率λ(S)对人口参数的随机弹性提供了一种衡量总体人口反应的合适方法，因为它既包括人口参数变化的直接影响，也包括通过年龄结构变化产生的间接影响。从25个生活史不同的哺乳动物种群中，我们研究了生活节奏和种群增长率如何影响人口统计响应(以随机弹性的直接和间接分量对波长的相对贡献衡量(S))。我们发现，在短命物种中，由于一岁存活率的增加而导致的种群结构的变化会导致Lambda(S)的额外增加，而在长寿物种中，同样的种群结构变化会导致Lambda(Lambda)的减少。因此，与长寿物种相反，短寿命物种表现出一种繁荣-萧条的生活史策略，对这种策略而言，长寿命抑制了年龄结构变化的人口统计学后果。无论物种的生活史策略如何，成虫存活率的增加导致种群年龄结构的变化，由于成熟个体在种群中所占比例的增加，导致Lambda(S)的额外增加。相反，由于繁殖性能的提高而引起的种群年龄结构的变化导致了Lambda(S)的减少，这是由于未成熟个体在种群中的比例增加所致。我们对哺乳动物随机弹性模式的比较分析表明，在短寿命物种和长寿命物种之间存在不同的人口对年龄结构变化的反应，这提高了我们对不同环境中与物种特定生活节奏相关的种群动态的理解。
In stochastic environments, a change in a demographic parameter can influence the population growth rate directly or via a resulting impact on age structure. Stochastic elasticity of the long-run stochastic growth rate lambda(s) to a demographic parameter offers a suitable way to measure the overall demographic response because it includes both the direct effect of changing the demographic parameter and its indirect effect through changes in the age structure. From 25 mammalian populations with contrasting life histories, we investigated how pace of life and population growth rate influence the demographic responses (measured as the relative contributions of the direct and indirect components of stochastic elasticity on lambda(s)). We found that in short-lived species, the change in population structure resulting from an increase in yearling survival leads to an additional increase in lambda(s), whereas in long-lived species, the same change in population structure leads to a decrease. Short-lived species thus display a boom-bust life history strategy contrary to long-lived species, for which the long lifespan dampens the demographic consequences of changing age structure. Irrespective of the species' life history strategy, the change in population age structure resulting from an increase in adult survival leads to an additional increase in lambda(s) due to an increase of the proportion of mature individuals in the population. On the contrary, a change in population age structure resulting from an increase of reproductive performance leads to a decrease in lambda(s) that is due to the increase of the proportion of immature individuals in the population. Our comparative analysis of stochastic elasticity patterns in mammals shows the existence of different demographic responses to changes in age structure between short-and long-lived species, which improves our understanding of population dynamics in variable environments in relation to the species-specific pace of life.