Córdoba-Aguilar A, López-Valenzuela A, Brunel O
Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Apdo. Postal 70-275, Ciudad Universitaria, 04510 Mexico D.F., Mexico.
Genetica. 2010 Dec;138(11-12):1141-6. doi: 10.1007/s10709-010-9504-6. Epub 2010 Oct 12.
Static allometry of sexually selected traits has been the subject of intense research recently. However, some pitfalls for this kind of research are: (a) the functions of sexual traits are largely unknown; (b) more than one body size indicator must be measured; and, (c) allometry must be examined under different environmental circumstances to see whether allometric values change. Using Hetaerina americana damselflies, we investigated the type of allometry exhibited by a wing red spot and aedeagal width. These traits are positively selected during pre-copulatory male-male contests and post-copulatory female stimulation, respectively. As body size indicators, we used wing length and head width. It has been documented that expression of both sexual traits varies throughout the year. Thus, allometry was examined in different times of the year. We also investigated the allometry of aedeagal width and vaginal width at the zone where female stimulation takes place. We found no clear pattern of any allometric relationship for male and female traits and for both body size indicators at all times sampled. Our results contrast with patterns of negative allometry exhibited by genital traits in other animals.
性选择性状的静态异速生长最近一直是深入研究的主题。然而，这类研究存在一些陷阱：（a）性性状的功能大多未知；（b）必须测量不止一种身体大小指标；以及，（c）必须在不同环境条件下检查异速生长，以查看异速生长值是否变化。我们使用美洲赫氏豆娘，研究了翅红斑和阳茎宽度所表现出的异速生长类型。这些性状分别在交配前的雄性间竞争和交配后的雌性刺激过程中受到正向选择。作为身体大小指标，我们使用了翅长和头宽。据记载，这两种性性状的表达全年都有所变化。因此，我们在一年中的不同时间检查了异速生长情况。我们还研究了在雌性受到刺激的区域阳茎宽度和阴道宽度的异速生长。在所有采样时间，我们均未发现雄性和雌性性状以及两种身体大小指标之间存在任何明显的异速生长关系模式。我们的结果与其他动物生殖器官性状所表现出的负向异速生长模式形成对比。
