Ewen K R, Temple-Smith P D, Bowden D K, Marinopoulos J, Renfree M B, Yan H
Department of Anatomy, Monash University, Clayton, Victoria, Australia.
J Reprod Fertil. 1993 Sep;99(1):33-7. doi: 10.1530/jrf.0.0990033.
The tammar wallaby has a polygynous mating system in which the dominant male usually controls initial access to oestrous females by mating first and then guarding the female from the advances of other subordinate males. In this study we used DNA fingerprinting with a human 3' hypervariable region (HVR) alpha globin probe to examine the paternity of pouch young progeny from 13 female tammars that were given continual access during the breeding season to a group of four sexually mature males. Constant individual-specific DNA profiles were observed for each animal. Paternity for 22 pouch young was successfully assigned using visual and computer-based analyses. However, no statistical difference was observed between the number of young sired by any of the four males (chi 2 = 2, d.f. = 3, P > 0.1). Mate guarding by the dominant male in our captive breeding group was not, therefore, sufficient to prevent successful subsequent matings by subordinates nor to enhance the genetic contribution of this male to the next generation. In each analysis, visual and computer assignments of paternity coincided, and these concurred with the results of a relatedness test which found that a large number of DNA bands were shared by sires and their progeny. The results from this paternity study show that first mating and subsequent mate guarding by the dominant male tammar wallaby in our captive group do not significantly skew the outcome of paternity towards this male and away from other males that subsequently mate with each female.
帚尾袋鼩具有一雄多雌的交配系统,在该系统中,占主导地位的雄性通常通过首先交配,然后防止雌性受到其他从属雄性的求偶行为,来控制对处于发情期雌性的最初接触机会。在本研究中,我们使用人类3'高变区(HVR)α珠蛋白探针进行DNA指纹分析,以检测13只雌性帚尾袋鼩育儿袋中幼崽的父系情况,这些雌性在繁殖季节可持续接触一组4只性成熟雄性。每只动物都观察到了恒定的个体特异性DNA图谱。通过视觉和基于计算机的分析成功确定了22只育儿袋中幼崽的父系。然而,在这4只雄性中,任何一只雄性所产幼崽的数量之间未观察到统计学差异(卡方 = 2,自由度 = 3,P > 0.1)。因此,在我们的圈养繁殖群体中,占主导地位的雄性的配偶守护行为不足以阻止从属雄性随后成功交配,也不足以增加该雄性对下一代的遗传贡献。在每次分析中,父系的视觉和计算机判定结果一致,并且这些结果与亲缘关系测试的结果相符,该测试发现父系及其后代共享大量DNA条带。这项父系研究的结果表明,在我们的圈养群体中,占主导地位的雄性帚尾袋鼩首先交配并随后进行配偶守护,并不会显著使父系结果偏向该雄性,而远离随后与每只雌性交配的其他雄性。