Beauty is in the eye of the beholder—even if that beholder is a barn swallow. Depending on where the birds live, some of them may favor mates with a paler chest color while others find a redder chest ...

1. In many parts of the world, changes in agricultural land-use have led to significant declines of bird species, including aerial insectivores such as barn swallows. In particular, barn swallow ...

This is a preview. Log in through your library . Abstract Life history theory describes the optimization of important trade-offs within an individual's lifetime and predicts that an individual's ...

Beauty is in the eye of the beholder—even if that beholder is a barn swallow. Depending on where the birds live, some of them ...

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