Weeks S C, Crosser B R, Gray M M
Program in Evolution, Ecology and Organismal Biology, Department of Biology, University of Akron, Akron, Ohio, USA.
J Evol Biol. 2001 Jan 8;14(1):83-94. doi: 10.1046/j.1420-9101.2001.00251.x.
Androdioecy (populations of males and hermaphrodites) is a rare reproductive form, being described from only a handful of plants and animals. One of these is the shrimp Eulimnadia texana, which has populations comprised of three mating types: two hermaphroditic types (monogenics and amphigenics) and males. In a recent study, the amphigenic hermaphrodites were found to be in greater abundance than that predicted from a model of this mating system. Herein, we compare the relative fitness of offspring from amphigenic and monogenic siblings, attempting to understand the greater relative abundance of the former. Populations started with offspring from selfed monogenic hermaphrodites had a net reproductive rate (R) 87% that of offspring from their amphigenic siblings. Additionally, within populations of amphigenic offspring (which included males, monogenics and amphigenics), amphigenics survived longer than monogenics. These differences help to explain the increased relative abundance of amphigenics in natural populations, but amphigenics continue to be more abundant than expected.
雄雌同体（由雄性和雌雄同体组成的种群）是一种罕见的繁殖形式，仅在少数植物和动物中被描述过。其中之一是德克萨斯真虾，其种群由三种交配类型组成：两种雌雄同体类型（单基因型和双基因型）和雄性。在最近的一项研究中，发现双基因雌雄同体的数量比这种交配系统模型预测的要多。在此，我们比较了双基因和单基因同胞后代的相对适合度，试图了解前者相对数量更多的原因。以自交单基因雌雄同体的后代开始的种群，其净繁殖率（R）是其双基因同胞后代的87%。此外，在双基因后代的种群中（包括雄性、单基因型和双基因型），双基因型的存活时间比单基因型长。这些差异有助于解释自然种群中双基因型相对数量增加的原因，但双基因型的数量仍然比预期的要多。
