Key Laboratory of Biodiversity Science and Ecological Engineering of Ministry of Education, School of Life Sciences, Beijing Normal University, Beijing, China.
PLoS One. 2013 Aug 5;8(8):e69889. doi: 10.1371/journal.pone.0069889. Print 2013.
Males will alter their mating behavior to cope with the presence of their competitors. Even exposure to odors from potential competitors can greatly increase male ejaculate expenditure in a variety of animals including insects, fishes, birds and rodents. Major efforts have been made to examine males' plastic responses to sperm competition and its fitness benefits. However, the effects of competitor absence on male's sexual motivation and behaviors remain unclear, which has been proposed to be one of the causes for the poor sexual performance of some captive mammals. This study revealed that sexual motivation can be greatly enhanced in captive male giant pandas (Ailuropoda melanoleuca) by exposure to chemosensory cues from either one or three conspecifics males. It had been shown that potential rivals' odors increased males' chemosensory investigation behavior, as well as their observing, following and sniffing behaviors towards estrous females. Behaviors changed regardless of the number of rivals (one or three). Our results demonstrate the effects of potential competition on male giant pandas' sexual motivation and behavioral coping strategy. We anticipate that our research will provide a fresh insight into the mechanisms underlying poor sexual performance in male captive mammals, and valuable information for the practical management and ex situ conservation of endangered species.
雄性动物会改变其交配行为以应对竞争对手的存在。即使暴露在潜在竞争对手的气味中，也能在包括昆虫、鱼类、鸟类和啮齿动物在内的多种动物中大大增加雄性的精液支出。人们已经做出了重大努力来研究雄性对精子竞争的可塑性反应及其对适应度的好处。然而，竞争缺失对雄性性动机和行为的影响仍不清楚，这被认为是一些圈养哺乳动物性表现不佳的原因之一。本研究表明，通过接触一只或三只同种雄性的化学感觉线索，圈养雄性大熊猫（Ailuropoda melanoleuca）的性动机可以大大增强。已经表明，潜在对手的气味增加了雄性的化学感觉探究行为，以及它们对发情雌性的观察、跟随和嗅探行为。无论对手数量多少（一只或三只），行为都会发生变化。我们的研究结果表明，潜在竞争对雄性大熊猫的性动机和行为应对策略有影响。我们预计，我们的研究将为理解雄性圈养哺乳动物性表现不佳的机制提供新的视角，并为濒危物种的实际管理和异地保护提供有价值的信息。
