Evolutionarily stable reproductive strategies in sexual organisms .2. Dioecy and optimal resource allocation
Evolutionarily stable reproductive strategies in sexual organisms .2. Dioecy and optimal resource allocation
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DOI：
10.1086/285898
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发表时间：
1996-06-01
影响因子：
2.9
通讯作者：
Zhao, SL
中科院分区：
文献类型：
--
作者：
Zhang, DY;Jiang, XH;Zhao, SL
1116美国自然主义者心中的物种。在这里，我们和其他地方一样（Zhang和Wang，1994），只能处理没有年龄结构的重叠世代;也就是说，年龄对成年人的存活率和繁殖率没有影响。我们将依靠单位点理论作为论证，以在恒定的、密度无关的环境中找到ESS资源分配（Charnov 1982，1988; Stearns 1992）。男性和女性是分开考虑的。一个人可利用的总资源是有限的，而且可能存在性别差异。雄性将资源分为两类：花粉的生产和繁殖后的生存。与此相反，女性被认为必须将全部可用资源划分为三个相互竞争的功能：生产儿子，生产女儿和繁殖后的生存。在一个控制雄性和雌性资源分配的常染色体位点上，让共同纯合子（AA）的雌性（雄性）分配总资源的E（H）比例用于生殖，1-E（1-H）比例用于生存。对于女性来说，分配给生殖的资源中有比例r给儿子，1-r给女儿。因此，在我们的模型中有三个决策变量，两个用于女性，一个用于男性。考虑一个罕见的突变等位基因（B）的命运，它使雌性杂合子AB将总资源的比例E '分配给生殖，将生殖分配的比例r'分配给儿子，而雄性杂合子AB将资源比例H '分配给花粉生产，将资源比例1-H'分配给繁殖后的存活。虽然突变体是罕见的，我们只需要考虑杂合子（AB）的传播，以了解当前的资源分配模式，E，r和H，是否稳定的入侵，一些新的资源分配模式（E '，r'，和H '）。假设纯合子（AA）的雌性群体在时间T的大小为Nf（T），雄性群体在时间T的大小为Nm（T）。定义Pf为每年雌性成虫存活率，Pm为每年雄性成虫存活率，f为雌性产生的有效女儿数（即成年时计算的雌性后代数量），m为雌性产生的有效儿子数，g为雄性产生的花粉量。假设这些参数是其各自资源输入的函数。因此，我们可以写Pf= Pf（1-E），Pm= Pm（1-H），g= g（H），m= m（Er），f= f（E [1-r]）。基因型AB与AA在资源分配上不同，因此在这些参数的值上也不同，这些参数用撇号表示。根据Charlesworth（1980）和Charnov（1982）的观点，我们假设雌性的生育力不受花粉可用性的限制。AA的雌性种群和雄性种群的年动态可描述如下：
1116 THE AMERICAN NATURALIST species in mind. Here we, as elsewhere,(Zhang and Wang 1994), can only treat overlapping generations without age structure; that is, age has no effect on adult rates of survival and reproduction. We will rely on single-locus theory as the argument to find the ESS resource allocation in a constant, density-independent environment (Charnov 1982, 1988; Stearns 1992). Males and females are considered separately. Total resources available to an individual are limited and with possible sex differences. A male divides the resources into two categories: the production of pollen and postbreeding survival. By contrast, a female is assumed to have to divide total available resources into three competing functions: the production of sons, the production of daughters, and postbreeding survival. At an autosomal ocus controlling resource allocation for both males and females, let the female (male) of the common homozygote(AA) allocate a propor-tion E (H) of total resource to reproduction and 1-E (1-H) to survival. For females, among the resources that are allocated to reproduction are proportions r to sons and 1-r to daughters. Hence, in our model there are three decision variables, two for females and one for males. Consider the fate of a rare mutant allele (B) that causes female heterozygotes AB to allocate a proportion E'of total resources to reproduction and r'of the reproductive allocation to sons, and male heterozygotes AB to allocate a resource fraction H'to pollen production and 1-H'to postbreeding survival. While the mutant is rare, we need only consider the spread of the heterozygote(AB) to know whether the current resource allocation pattern, E, r, and H, is stable to invasion by some new resource allocation patterns (E', r', and H'). Let the female population of homozygotes(AA) be of size Nf (T) and the male of size Nm (T) at time T. Define Pf as yearly female adult survival, Pm as yearly male adult survival, f as the effective number of daughters produced by a female (ie, the number of female Ioffspring counted at adulthood), m as the effective number of sons produced by a female, and g as the amount of pollen produced by a male. These parameters are assumed to be a function of their respective resource input. There-fore, we can write Pf= Pf (l-E), Pm= Pm (I-H), g= g (H), m= m (Er), and f= f (E [l-r]). Genotype AB differs from AA in the resource allocation and hence in the values of these parameters, denoted by a prime symbol. Following Charlesworth(1980) and Charnov (1982), we assume that the fertility of a female is not limited by pollen availability. The yearly dynamics of the female population and the male population of AA can be described as follows: