School of Computing, University of Wyoming, Laramie, WY 82071.
Haub School of Environment and Natural Resources, University of Wyoming, Laramie, WY 82072.
Proc Natl Acad Sci U S A. 2024 Mar 19;121(12):e2306389121. doi: 10.1073/pnas.2306389121. Epub 2024 Mar 4.
How animals refine migratory behavior over their lifetime (i.e., the ontogeny of migration) is an enduring question with important implications for predicting the adaptive capacity of migrants in a changing world. Yet, our inability to monitor the movements of individuals from early life onward has limited our understanding of the ontogeny of migration. The exploration-refinement hypothesis posits that learning shapes the ontogeny of migration in long-lived species, resulting in greater exploratory behavior early in life followed by more rapid and direct movement during later life. We test the exploration-refinement hypothesis by examining how white storks () balance energy, time, and information as they develop and refine migratory behavior during the first years of life. Here, we show that young birds reduce energy expenditure during flight while also increasing information gain by exploring new places during migration. As the birds age and gain more experience, older individuals stop exploring new places and instead move more quickly and directly, resulting in greater energy expenditure during migratory flight. During spring migration, individuals innovated novel shortcuts during the transition from early life into adulthood, suggesting a reliance on spatial memory acquired through learning. These incremental refinements in migratory behavior provide support for the importance of individual learning within a lifetime in the ontogeny of long-distance migration.
动物如何在其一生中（即迁徙的个体发育）完善迁徙行为，这是一个长期存在的问题，对于预测在不断变化的世界中迁徙者的适应能力具有重要意义。然而，由于我们无法从早期开始监测个体的运动，因此我们对迁徙的个体发育的理解受到限制。探索-精炼假说认为，学习塑造了长寿物种迁徙的个体发育，导致生命早期表现出更多的探索性行为，随后在生命后期表现出更快、更直接的运动。我们通过研究白头鹤（）如何在生命的头几年发展和完善迁徙行为，来检验探索-精炼假说。在这里，我们表明，幼鸟在飞行中减少能量消耗，同时通过在迁徙过程中探索新的地方来增加信息获取。随着鸟类年龄的增长和经验的增加，年龄较大的个体停止探索新的地方，而是更快、更直接地移动，导致迁徙飞行中的能量消耗增加。在春季迁徙期间，个体在从早期生活过渡到成年期的过程中创新了新的捷径，这表明它们依赖于通过学习获得的空间记忆。这些迁徙行为的逐渐完善为个体学习在长距离迁徙的个体发育中的重要性提供了支持。
