鸳鸯种内巢寄生繁殖对策

发布时间：2018-05-10 07:13

本文选题：繁殖对策 + 种内巢寄生　；参考：《东北师范大学》2016年博士论文

【摘要】：种内巢寄生(CBP)是广泛存在的雌性选择性繁殖对策。寄生个体将卵产于同种其它个体巢中,并由后者代为照顾子代而节省能量投入。研究者对种间巢寄生(IBP)的研究较为深入,但对CBP研究相对较少,包括鸳鸯Aix galericulata在内的很多物种CBP的发生机制尚不清楚。先前对鸳鸯CBP的研究,主要通过野外观察的方法鉴定寄生,但非分子方法常表现出较低的精度。本研究利用分子标记技术对鸳鸯种内巢寄生行为进行了研究,探讨鸳鸯CBP发生的影响因素。鸳鸯原生种群的相关研究很少,本研究对人工巢箱条件下该物种的繁殖生态进行了调查。每巢的日产卵率为1.1枚/日,成功孵化巢的窝卵数为13.4枚,弃巢率47.5%,孵化成功率85.5%。环志研究发现鸳鸯雌鸟具有栖息地忠实性,约40%雌性成鸟次年仍返回原繁殖地。基于分子标记的亲权分析结果显示:鸳鸯CBP发生频率(寄生巢:77.5%;寄生后代:40.9%)明显高于以往对鸳鸯原生种群和引进种群的研究结果,且较多数利用分子手段进行寄生鉴定的水鸟CBP发生频率高。本研究比较了分子方法与基于产卵节律、窝卵数或卵形态差异三种非分子方法鉴定巢寄生的准确性,基于巢日产卵数量、窝卵数及卵形态的鉴定结果均在不同程度上低估了寄生频率(分别将30.4%、27.5%和12.5%的繁殖巢误判为非寄生巢)。其中,卵形态鉴定法较为可靠,且省时省力,鉴定结果具有一定参考价值。对鸳鸯寄主繁殖对策研究发现:1)CBP不是巢址竞争的副产物,半数以上巢箱未被占用,巢址可获得性不是限制因素;卵添加实验导致产寄生卵的巢均未被雌性接管孵化(无巢竞争者出现)。2)CBP是鸳鸯一种选择性繁殖对策,在同一繁殖季每个寄生个体同时采取占巢产卵和寄生两种繁殖方式;同一雌性个体在不同年份的繁殖对策(寄生与非寄生)不同;CBP发生的时间贯穿整个繁殖季。3)寄主对宿主的选择与巢间距无显著相关性。4)每个寄主选择多个宿主巢产卵,每个寄主平均产4.89 ±2.98(1-13,n=35)个寄生卵;寄生卵平均分布于2.66±1.3(1-6;n = 35)个巢中;在每个宿主巢内平均产1.65±1.08(1-5,n = 89)个卵。针对寄主寄生原因的众多假说,本研究结果与增加繁殖力假说一致。宿主代价研究结果表明:1)较大的窝卵数需要更长的孵化期,每增加一枚卵孵化期延长0.14天。窝卵数增加未显著降低出雏率,且出雏率在寄生与非寄生巢间无显著差异;2)CBP未影响宿主在自身巢中的产卵数量和总卵数(宿主无窝卵数调整且很少拒绝寄生卵);3)鸳鸯弃巢率较高,且47.5%(n = 40)弃巢不能排除受CBP影响;根据理论公式估测,只有当宿主卵数/寄主卵数比值1/6时,弃巢代价会小于孵化代价,因鸳鸯弃巢行为多发生在产卵阶段,且产卵数较少时,因此,弃巢可能对宿主的繁殖适合度影响较小。4)宿主和寄主存在较近的亲缘关系,鸳鸯的巢寄生行为可能会增加宿主兼性适合度收益。总之,鸳鸯寄生个体将寄生卵分配于多个宿主巢,且宿主和寄主存在较近的亲缘关系,虽弃巢可能是其采取的反寄生对策,但弃巢可能对宿主的繁殖适合度影响较小,因此,CBP可能是鸳鸯雌性个体增加适合度收益的一种选择性繁殖对策。未来仍需开展深入研究,确定宿主和寄主详尽的适合度收益和代价,以充分c彩驹а霤BP进化的适应机制。
[Abstract]:The nests parasitism (CBP) is a widely existing female selective breeding strategy. The parasitic individual produces eggs in other individual nests and is replaced by the latter generation to save energy. Researchers have studied the nests parasitism (IBP) more deeply, but there are relatively few studies on CBP, including many species of C, including the mandarin duck Aix galericulata. The mechanism of the occurrence of BP is still unclear. Previously, the study of mandarin ducks CBP mainly identified parasitism by field observation, but the non molecular methods often showed low accuracy. This study used molecular markers to study the parasitism of the nests in mandarin ducks and explore the influencing factors of the origin of mandarin ducks CBP. In this study, the reproductive ecology of the species under the artificial nest box was investigated. The egg rate per nest was 1.1 / day, the number of nest eggs was 13.4, the rate of abandoned nest was 47.5%. The success rate of hatching 85.5%. discovered that the mandarin duck had a habitat loyalty, and about 40% female adult birds returned to the original breeding ground in the next year. The results of parental weight analysis of sub markers showed that the frequency of CBP (parasitic nest: 77.5%; parasitic progeny: 40.9%) was significantly higher than the previous studies on the primary and imported populations of mandarin ducks, and the frequency of water birds CBP was higher than most of the parasitic identification by molecular means. This study compared the molecular methods and eggs based on oviposition and nest eggs. Three non molecular methods were used to identify the accuracy of nest parasitism. Based on the number of nest eggs, number of fossa eggs and egg morphology, the parasitic frequency was underestimated to varying degrees (30.4%, 27.5% and 12.5% of the reproductive nests were misjudged as non parasitic nests, respectively). The results showed a certain reference value. The study of the host breeding of mandarin ducks found that: 1) CBP is not a by-product of the competition of the nest site, more than half of the nest box is not occupied, the availability of nest site is not a limiting factor; the egg addition experiment leads to the nest of parasitic eggs which are not hatched by the female takeover (no nest competitor appears).2) CBP is a selective propagation of mandarin ducks. In the same breeding season, each parasitic individual took two species of eggs and parasitism at the same time; the reproductive strategies of the same female individuals were different in different years (parasitism and non parasitism); the time of CBP occurred throughout the whole breeding season.3) the host selection had no significant correlation with the nest distance of host.4). The host nest spawned, each host produced an average of 4.89 + 2.98 (1-13, n=35) parasitic eggs, and the parasitic eggs were distributed in 2.66 + 1.3 (1-6; n = 35) nests, with an average of 1.65 + 1.08 (1-5, n = 89) eggs in each host nest. The results of this study were in accordance with the hypothesis that the host parasitism was due to the increase of the fecundity hypothesis. The results of the host cost study showed that 1) 1) the number of larger nest eggs needs longer incubation period, and the incubation period of each egg is prolonged by 0.14 days. The number of nest eggs is not significantly reduced, and there is no significant difference between the parasitic and non parasitic nests; 2) CBP does not affect the number of eggs and the total number of eggs in the host's nest (the number of host eggs without the nest egg is adjusted and the parasitic egg is rarely rejected); 3) The abandoned nest rate of mandarin ducks is high, and the 47.5% (n = 40) abandoned nest can not exclude the effect of CBP. According to the theoretical formula, it is estimated that the cost of abandoning nesting will be less than the cost of hatching when the host egg number / host egg number ratio is 1/6, because the abandoned nest behavior of the mandarin ducks is mostly in the spawning stage, and the number of eggs is less, therefore, the abandoning nest may affect the reproductive fitness of the host. Small.4) there is a close relationship between the host and host, and the parasitic behavior of the mandarin ducks may increase the benefit of the host facultative fitness. In a word, the parasitic individuals of the mandarin ducks distribute the parasitic eggs in many host nests, and there is a close relationship between the host and the host, although the abandoned nest may be the anti parasitic countermeasure it takes, but the abandoned nest may be against the host. The effect of reproductive fitness is small, so CBP may be a selective breeding strategy to increase the fitness benefit of female ducks. In the future, further research is still needed to determine the suitable degree of benefit and cost of host and host for the adaptation mechanism of BP evolution of C colourful colt.

【学位授予单位】：东北师范大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：Q958

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