Migrating is a major physical challenge. The energy required to fly hundreds or thousands of miles in a short span leaves birds with little room for error and vulnerable to many natural and human-caused threats. In preparation for such perilous journeys, birds undergo physical transformation unmatched by human gains from years of training.
To fly vast distances between breeding and wintering grounds, birds can shrink their internal organs, rapidly gain and burn through fat stores, reduce sleep requirements, and more. Here are some of the incredible ways birds morph their bodies for migration. |
|
|
|
|