51�Թ�

“This study is one of surprisingly few that compellingly document sympatric speciation caught in the act” in vertebrates, says Martha Muñoz, an evolutionary biologist at Yale University who was not involved with the work.

At first glance, sympatric hybridization makes no evolutionary sense, and even poses a threat to species diversity.

The focus on neighboring dinosaurs - or what experts call sympatric species - is a critical part of the test.

Exactly what this grand, evolving mess means for the distribution and health of hornbill populations, and for sympatric plants and animals, is neither simple nor clear.

Multiple sympatric species specialize on the same sex flowers of the same fly host-plant species—which suggests extreme niche overlap; however, niche partitioning was exposed by interactions between wasps and flies.