A nice feature on the cliff swallow project, by Conor Gearin, appeared in issue 4 of The New Territory magazine. Conor's article focused on the 1996 weather kill and its consequences for the rapid evolution of morphology in cliff swallows.
The revision of the 1995 cliff swallow account in the Birds of North America series was published, after an extensive revision and updating. It had been badly out of date, given the many publications on cliff swallows since the first version.
Collaborator Mary Bomberger Brown, along with co-authors Allison Johnson (a former research assistant on this project) and Jonathan Mitchell, published a paper on convergent evolution in social swallows in Ecology and Evolution. The paper reports results of analyses showing that solitary species of swallows show highly variable morphology, while more social swallows show much less absolute variance in morphological traits. The physical traits seen in the social species (such as cliff swallows) lead to a distinctive flight style that increases maneuverability and foraging success and reduces the likelihood of in-flight collisions within large flocks. Selection for these traits has been less intense in solitary species, potentially explaining their more variable morphology.
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