An analysis of skull and vertebrae fossils suggests that an early relative of giraffes butted heads to compete for mates, which may reveal why modern giraffes are so throaty.
Researchers tracked the movements of endangered caribou and sequenced a portion of their genomes to determine which genes may influence migratory behavior.
More than two-thirds of mammals in Africa and the Arabian Peninsula went extinct during the Eocene-Oligocene transition some 30 million years ago, a study finds.