Sexual patterns of prebreeding energy reserves in the common frog Rana temporaria along a latitudinal gradient
Sexual patterns of prebreeding energy reserves in the common frog Rana temporaria along a latitudinal gradient
复制标题
DOI：
10.1111/j.1600-0587.2009.05352.x
复制
发表时间：
2009-10-01
期刊：
影响因子：
5.9
通讯作者：
Merila, Juha
中科院分区：
文献类型：
--
作者：
Jonsson, K. Ingemar;Herczeg, Gabor;Merila, Juha
储存能量的能力是面临长期没有能量收入的生物体的重要生活史特征，特别是对于资本繁殖者，如温带两栖动物，它们在繁殖期间依赖储存的能量。然而，大规模的比较研究的能量储存在不同的环境限制的能量分配的人群是稀缺的。研究了沿着1600 km纬度梯度穿越斯堪的纳维亚半岛（年活动期为3-7个月）的8个暴露于不同环境条件下的普通蛙（Rana temporaria）种群春季（冬眠后和繁殖前）的能量储存模式。对瘦体重（取出内脏的体重）、脂肪体重量、肝脏重量和肝脏脂肪含量的分析表明：1）两性冬眠后/繁殖前的能量储存随着纬度的增加而增加; 2）雄性通常比雌性具有更大的能量储存; 3）两性之间的能量储存差异向北减小。向北更大的能源储备可以作为一个缓冲区，以应对较难预测和/或不太良性的天气条件下，在短期活动期间，也可能代表一个风险规避策略与更明显的iteroparous生活史。在女性，连续和重叠的卵黄发生活动在北方也可能需要更多的储备在早春。一般的性别差异可能是这样一个事实的结果，即在我们采样的时候，女性已经投入了他们的精力在给定的一年繁殖（即他们的鸡蛋已经排卵），而男性的主要生殖活动（例如呼叫，交配搜索，性竞争）发生在季节的后期。
The ability to store energy is an important life history trait for organisms facing long periods without energy income, and in particular for capital breeders such as temperate zone amphibians, which rely on stored energy during reproduction. However, large scale comparative studies of energy stores in populations with different environmental constraints on energy allocation are scarce. We investigated energy storage patterns in spring (after hibernation and before reproduction) in eight common frog Rana temporaria populations exposed to different environmental conditions along a 1600 km latitudinal gradient across Scandinavia (range of annual activity period is 3-7 months). Analyses of lean body weight (eviscerated body mass), weight of fat bodies, liver weight, and liver fat content, showed that 1) post-hibernation/pre-breeding energy stores increased with increasing latitude in both sexes, 2) males generally had larger energy reserves than females and 3) the difference in energy stores between sexes decreased towards the north. Larger energy reserves towards the north can serve as a buffer against less predictable and/or less benign weather conditions during the short activity period, and may also represent a risk-averse tactic connected with a more pronounced iteroparous life history. In females, the continuous and overlapping vitellogenic activity in the north may also demand more reserves in early spring. The general sexual difference could be a consequence of the fact that, at the time of our sampling, females had already invested their energy into reproduction in the given year (i.e. their eggs were already ovulated), while the males' main reproductive activities (e.g. calling, mate searching, sexual competition) occurred later in the season.