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

雄性非洲象（Loxodonta africana）对蝇尿的行为反应。雄性大象通常表现出大多数哺乳动物社会中雄性大象的统治关系；体型较大的个体对体型较小的个体具有支配地位。然而，麝香发作（睾丸激素升高和高度攻击性的时期）暂时提高了雄性比任何非麝香雄性的统治地位，无论大小或年龄。典型表现为与女性的联系增加，性活动增加，颞腺分泌和几乎连续的尿滴，musth被描述为类似于有蹄类动物的发情期。然而，与发情期不同的是，发情期贯穿全年，而且在一个种群中是不同步的，所以只有几头公牛同时处于发情期。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老年痴呆的可能性。一次发情期可能持续几天到五个多月，通常随着男性年龄的增长而增加。维持这种状态需要消耗大量的能量，因此男性的身体会随着这种状态的持续而下降。这项研究探索了雄性非洲象在发乳期间通过尿滴来传递化学信号的可能性。通过研究发情期间信号的时间模式，本研究探讨了发情在种群水平上的不同步如何部分地解释为个体维持这种生理上昂贵的状态和避免与其他雄性发情的直接竞争的经济学。因此，这些结果可能会为当前的性选择理论、信号理论和雄性竞争策略提供更多的启示。本研究也为进一步探索通过尿中霉味信号抑制或刺激雄性霉味奠定了基础。

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.