School of Natural Sciences, University of Stirling, Stirling, UK.
Biol Lett. 2013 Feb 13;9(2):20130011. doi: 10.1098/rsbl.2013.0011. Print 2013 Apr 23.
Growth from conception to reproductive onset in African elephants (Loxodonta africana) provides insights into phenotypic plasticity, individual adaptive plastic responses and facultative maternal investment. Using growth for 867 and life histories for 2652 elephants over 40 years, we demonstrate that maternal inexperience plus drought in early life result in reduced growth rates for sons and higher mortality for both sexes. Slow growth during early lactation was associated with smaller adult size, later age at first reproduction, reduced lifetime survival and consequently limited reproductive output. These enduring effects of trading slow early growth against immediate survival were apparent over the very long term; delayed downstream consequences were unexpected for a species with a maximum longevity of 70+ years and unpredictable environmental experiences.
从受孕到生殖开始的非洲象（Loxodonta africana）生长过程提供了对表型可塑性、个体适应可塑性反应和兼性母性投资的深入了解。通过对 40 年间 867 只大象的生长情况和 2652 只大象的生活史进行研究，我们发现，母象经验不足加上生命早期的干旱会导致雄性大象的生长速度减慢，雌雄两性的死亡率都会升高。在哺乳期早期生长缓慢与成年后体型较小、首次繁殖年龄较大、终生存活率降低以及繁殖产出有限有关。这种以牺牲早期生长速度换取即时生存的持久效应在很长一段时间内都很明显；对于一个最长寿命可达 70 岁以上且环境经历不可预测的物种来说，这种延迟的下游后果是出乎意料的。
