Temperature and diet modified swimming behaviors of larval sand dollar
Temperature and diet modified swimming behaviors of larval sand dollar
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温度和饮食改变沙钱鱼幼虫的游泳行为
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
D. Grünbaum
中科院分区：
文献类型：
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作者：
Kit Yu Karen Chan;D. Grünbaum
海洋无脊椎动物幼体的游泳行为对幼体的扩散和存活起着关键作用，因此对成体种群动态有重要影响。然而，到目前为止，没有足够的定量信息存在于幼虫游泳，以了解和预测大多数海洋无脊椎动物物种的游泳运动。先前的研究表明，幼虫在较低的温度下游得更慢，因此，在经历温度变化时可能难以调节深度。在必需脂肪酸组成方面改善饮食质量已被建议增加许多生物体的耐寒性。我们使用非侵入性视频跟踪技术来量化沙元Dendrasterexcentricus幼虫的游泳，这些幼虫在4种脂肪酸分布不同的藻类饲料中饲养，然后暴露于20至12°C的生态相关温度下降。饲料质量的差异导致了8臂幼虫阶段的显著形态差异，并且对游泳模式存在显著的饲料-温度互作效应。虽然幼虫游泳速度下降，在所有饮食治疗的温度下降，净垂直速度的幼虫没有减少。幼虫游泳轨迹的螺旋几何形状的变化表明，幼虫通过减少水平运动来补偿游泳速度的降低，从而保持其调节深度的能力。所观察到的补偿机制有效地规避了由于温度降低而对游泳的限制。更一般地说，视频跟踪自由游泳的幼虫可以产生定量数据，以告知biopropionically耦合模型，更好地预测后果的幼虫扩散的成年人口动态在当前和未来的环境条件下。
Swimming behaviors of marine invertebrate larvae play key roles in larval dispersal and survival and, hence, have important consequences for adult population dynamics. However, to date, insufficient quantitative information exists on larval swimming to understand and predict swimming movements in most marine invertebrate species. Previous work suggests that larvae swim more slowly at lower temperatures and, consequently, might have difficulty regulating depth when experiencing temperature changes. Improved diet quality in terms of essential fatty acid composition has been suggested to increase cold tolerance in many organisms. We used non-invasive videotracking techniques to quantify swimming in larvae of the sand dollar Dendraster excentricus, raised on 4 algal diets differing in their fatty acid profiles and then exposed to an ecologically relevant temperature decrease from 20 to 12°C. Differences in diet quality led to significant morphological differences by the 8-arm larval stage, and there were significant diet-temperature interaction effects on swimming patterns. While larval swimming speeds decreased as temperature decreased across all diet treatments, net vertical velocities of larvae did not decrease. Changes in helical geometries of larval swimming trajectories suggest that larvae compensate for reduced swimming speeds by reducing horizontal movement, thus preserving their ability to regulate depth. The observed compensatory mechanism effectively circumvents constraints on swimming due to lowered temperatures. More generally, video-tracking of free-swimming larvae can yield quantitative data to inform biophysically coupled models that better predict consequences of larval dispersal for adult population dynamics under current and future environmental conditions.