DISSERTATION RESEARCH: Behavioral Responses of Male African Elephants (Loxodonta Africana) to Musth Urine

雄性非洲象(Loxodonta Africana)对尿的行为反应：苏珊·C·阿尔贝茨和朱莉·霍利斯特-史密斯公象通常表现出大多数哺乳动物社会中雄性大象的优势关系；较大的个体对较小的个体处于优势地位。然而，男性性欲发作(睾丸激素升高和攻击性强的时期)会暂时使男性的统治地位高于任何非性欲男性，无论其体型或年龄如何。它的典型特征是与雌性的联系增加，性活动增加，颞腺分泌和几乎持续的尿流，已被描述为类似于有蹄类的发情。然而，与发情不同的是，母牛一年四季都在发生，而且在一个种群中是不同步的，因此只有几头公牛同时处于杂交状态。其发病和持续时间的机制尚不清楚，但年龄、体型和身体状况都会影响个体经历MERH的可能性。一次性交周期可能只持续几天到五个月以上，通常随着男性年龄的增长而增加。维持这种状态是耗费精力的，因此雄性大象的身体状况会随着它的持续而下降。这项研究探索了雄性非洲象之间通过在怀孕期间滴尿来传递化学信号的可能性。通过研究MERH期间信号的时间模式，本研究调查了MERH种群水平的异步性如何部分地由个体经济学来解释，即维持这种生理代价高昂的条件和避免与MERH中的其他雄性直接竞争。因此，这些结果可能会为当前的性选择理论、信号理论和男性竞争策略提供更多的线索。这项研究也为未来探索通过尿液信号抑制或刺激男性的MHH奠定了基础。

Behavioral responses of male African elephants (Loxodonta africana) to musth urine.PI: Susan C. Alberts and Julie Hollister-Smith Male elephants generally exhibit the dominance relationships seen in males of most mammalian societies; a larger individual is dominant to a smaller individual. However, musth episodes (periods of elevated testosterone and high aggression) temporarily raise a male's dominance position above any non-musth male regardless of size or age. Typified by increased association with females, increased sexual activity, temporal gland secretions and nearly continual urine dribbling, musth has been described as similar to rut in ungulates. Unlike rut, however, musth occurs throughout the year and is asynchronous in a population, so that only a few bulls are in musth concurrently. The mechanisms underlying its onset and duration are not well understood, but age, size and physical condition all affect the likelihood that an individual will experience musth. A single musth period may last from just a few days to over five months, generally increasing as a male ages. Maintaining the condition is energetically costly, thus a male physically declines as it continues.This study explores the potential for chemical signaling between male African elephants via urine dribbling during musth. By examining the temporal patterns of signaling during musth, this study investigates how population level asynchrony of musth may in part be explained by individual economics of maintaining this physiologically expensive condition and of avoiding direct competition with other males in musth. As such, these results may shed additional light on current theories of sexual selection, signaling theory, and male competition strategies. This study also lays the groundwork for future exploration of possible suppression or stimulation of musth in males via urinary signals of musth.