Are snakes right-handed ? Asymmetry in hemipenis size and usage in gartersnakes (Thamnophis sirtalis)
Are snakes right-handed ? Asymmetry in hemipenis size and usage in gartersnakes (Thamnophis sirtalis)
复制标题
蛇是右撇子吗？
DOI：
--
复制
发表时间：
2000
期刊：
影响因子：
--
通讯作者：
R. Mason
中科院分区：
文献类型：
--
作者：
R. Shine;M. Olsson;M. Lemaster;I. Moore;R. Mason
雄性蛇拥有成对的生殖系统（睾丸、传出管、半阴茎和肾脏的相关组成部分），身体两侧各有一套独立的生殖系统。我们对吊袜带蛇（Thamnophis Sirtalis parietalis）的研究揭示了该系统显着的形态不对称性：身体右侧的睾丸、肾脏和半阴茎比左侧的大。来自野外和室外围栏的交配数据表明，这种不对称性对繁殖行为以及可能的繁殖成功具有影响。使用右侧半阴茎的交配产生了更大的凝胶状“交配塞”，因此可以更有效地延迟雌性的再交配。尽管在野外交配中两种半阴茎的总体使用率平均接近 50/50，但半阴茎的使用并不是随机的。雄性在连续的交配中倾向于交替使用半阴茎，这可能是因为插头材料的耗尽。此外，雄性吊袜带蛇在高体温下交配时优先使用较大的（右侧）半阴茎，也许是因为它们在这些条件下更能够做出微妙的姿势调整（从而选择更好的系统）。
Male snakes possess paired reproductive systems (testes, efferent ducts, hemipenes and associated components of the kidneys), with an independent set on either side of the body. Our studies on gartersnakes (Thamnophis sirtalis parietalis) reveal significant morphological asymmetry in this system: testes, kidneys, and hemipenes on the right-hand-side of the body are larger than those on the left. Data from matings in the field, and in outdoor enclosures, suggest that this asymmetry has implications for reproductive behavior and, possibly, reproductive success. Copulations using the right hemipenis produced a larger gelatinous ‘‘mating plug,’’ and may thus more effectively delay remating by the female. Although the overall usage of the two hemipenes in field matings averaged close to 50/50, hemipenis usage was not random. Males tended to alternate hemipenis use in successive matings, perhaps because of depletion of plug material. Also, male gartersnakes preferentially used their larger (right) hemipenis when mating at high body temperatures, perhaps because they are more able to make subtle postural adjustments (and thus, select the better system) under these conditions.