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Researchers Douglas J. Levey and F. Gary Stiles observed that many migratory neotropical landbirds eat fruit or nectar and live in forest edges or other open habitats with large shifts in temperature. The researchers hypothesized that these traits each independently contributed to the evolution of long-distance migration in many neotropical landbird species, supporting their hypothesis with data relating to Turdinae and other families of birds.
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Levey and Stiles’s hypothesis does not account for an additional possible evolutionary precursor to long-distance migration. W. Alice Boyle and Courtney J. Conway analyzed data on Machetornis rixosa and 378 other species of neotropical landbirds. They found that solitary foragers are more likely to migrate than birds that forage in groups, concluding that group foraging is consistently and negatively associated with long-distance migration.
Researchers Douglas J. Levey and F. Gary Stiles observed that many migratory neotropical landbirds eat fruit or nectar and live in forest edges or other open habitats with large shifts in temperature. The researchers hypothesized that these traits each independently contributed to the evolution of long-distance migration in many neotropical landbird species, supporting their hypothesis with data relating to Turdinae and other families of birds.
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Levey and Stiles’s hypothesis does not account for an additional possible evolutionary precursor to long-distance migration. W. Alice Boyle and Courtney J. Conway analyzed data on Machetornis rixosa and 378 other species of neotropical landbirds. They found that solitary foragers are more likely to migrate than birds that forage in groups, concluding that group foraging is consistently and negatively associated with long-distance migration.