Johnsen Arild, Pauliny Angela, Lifjeld Jan T, Blomqvist Donald
Natural History Museum, University of Oslo, Oslo, Norway.
Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden.
PLoS One. 2017 Aug 4;12(8):e0182446. doi: 10.1371/journal.pone.0182446. eCollection 2017.
Telomere length is related to aging in many eukaryotes and the rate of telomere attrition has been suggested to reflect individual genetic quality. Telomere length could thus have implications for mate choice. We investigated telomere length variation in bluethroat Luscinia svecica families with mixed paternity, including social parents, extra-pair fathers and nestlings, testing whether telomere length is associated with social and/or extra-pair mate choice through assortative mating or selection of mates with relatively long telomeres. In adults, relative telomere length (rTL) did not differ between the sexes, nor between two age categories. In chicks, however, rTL decreased with body mass at sampling (an index of nestling age). We found a positive correlation between the rTL of social mates, suggesting assortative mating with respect to telomere length or a correlative thereof. However, extra-pair males did not differ from social mates in rTL, and accordingly there was also no difference between within- and extra-pair young (i.e. half-siblings) when controlling for the effect of mass. We found no relationships between telomere length, age and fitness-related traits in adults, but an intriguing year-difference in telomere length in both sexes. In conclusion, we found no support for the idea that females choose extra-pair males based on their telomere length, but social mate choice seems to be influenced by rTL, possibly through its co-variation with aspects reflecting individual quality, like early arrival at the breeding grounds.
端粒长度与许多真核生物的衰老有关，并且有人提出端粒损耗速率能够反映个体的遗传质量。因此，端粒长度可能会影响配偶选择。我们研究了具有混合父权的蓝喉歌鸲家庭中的端粒长度变异情况，这些家庭包括社会父母、配偶外父亲和雏鸟，以测试端粒长度是否通过选型交配或选择具有相对较长端粒的配偶与社会和/或配偶外配偶选择相关联。在成年个体中，相对端粒长度（rTL）在性别之间以及两个年龄类别之间没有差异。然而，在雏鸟中，rTL随采样时的体重（雏鸟年龄的一个指标）而降低。我们发现社会配偶的rTL之间存在正相关，这表明在端粒长度或其相关因素方面存在选型交配。然而，配偶外雄性在rTL方面与社会配偶没有差异，因此在控制体重影响时，配偶内和配偶外的幼鸟（即同父异母或同母异父的兄弟姐妹）之间也没有差异。我们在成年个体中未发现端粒长度、年龄与适应性相关性状之间的关系，但在两性中都发现了有趣的端粒长度年度差异。总之，我们没有找到支持雌性基于端粒长度选择配偶外雄性这一观点的证据，但社会配偶选择似乎受到rTL的影响，可能是通过它与反映个体质量的方面（如早到达繁殖地）的共同变化。
