正文
“虽然我们相信所有的雌性每年都会交配，但他们仅在交配地停留一个小时内1到3天。而雄性要长得多，少则7天，长的可达21天，这似乎导致雄性老化速度更快。“弗里森博士说。
“女性每隔一年繁殖一次，繁殖成功要依赖它们的脂肪/能量储备。我们以前的研究表明，女性真正完成受精之前，可以将精子存储长达15个月或更长时间！”
加拿大马尼托巴省的剑纹带蛇种群。（Christopher R Friesen）
除了优先保护自己的身体以外，在加拿大马尼托巴省研究的雌性剑纹带蛇不会浪费能量照顾他们的后代，与大多数的蛇类是一致的。
原文链接：http://sydney.edu.au/news-opinion/news/2017/04/05/sex-obsession-a-killer-for-male-snakes--research-footage-shows.html
相关论文信息
题目
Age-related sex differences in body condition and telomere dynamics of red-sided garter snakes
作者
Nicky Rollings, Emily J. Uhrig, Randolph W. Krohmer, Heather L. Waye, Robert T. Mason, Mats Olsson, Camilla M. Whittington, Christopher R. Friesen
发表时间
5 April 2017
DOI
10.1098/rspb.2016.2146
摘要
Life-history strategies vary dramatically between the sexes, which may drive divergence in sex-specific senescence and mortality rates. Telomeres are tandem nucleotide repeats that protect the ends of chromosomes from erosion during cell division. Telomeres have been implicated in senescence and mortality because they tend to shorten with stress, growth and age. We investigated age-specific telomere length in female and male red-sided garter snakes, Thamnophis sirtalis parietalis. We hypothesized that age-specific telomere length would differ between males and females given their divergent reproductive strategies. Male garter snakes emerge from hibernation with high levels of corticosterone, which facilitates energy mobilization to fuel mate-searching, courtship and mating behaviours during a two to four week aphagous breeding period at the den site. Conversely, females remain at the dens for only about 4 days and seem to invest more energy in growth and cellular maintenance, as they usually reproduce biennially. As male investment in reproduction involves a yearly bout of physiologically stressful activities, while females prioritize self-maintenance, we predicted male snakes would experience more age-specific telomere loss than females. We investigated this prediction using skeletochronology to determine the ages of individuals and qPCR to determine telomere length in a cross-sectional study. For both sexes, telomere length was positively related to body condition. Telomere length decreased with age in male garter snakes, but remained stable in female snakes. There was no correlation between telomere length and growth in either sex, suggesting that our results are a consequence of divergent selection on life histories of males and females. Different selection on the sexes may be the physiological consequence of the sexual dimorphism and mating system dynamics displayed by this species.
