Many insect groups have evolved symbiotic relationships with bacteria that facilitate the acquisition of important new traits, promoting ecological niche diversification. This project focuses on feather-feeding bird lice, which have repeatedly and independently evolved symbiotic relationships with bacteria to obtain essential B-vitamins that are lacking in a diet of feather keratin. The unusually uniform and simplified lifestyle of these lice presents a unique opportunity to study the evolutionary outcome of repeated acquisition of symbionts under similar conditions. Thus, the system provides a symbiotic analog of Stephen Jay Gould’s thought experiment “replaying the tape of life” or, in this case, the tape of (symbiosis in) lice. We are using a combination of co-phylogenomics, comparative genomics, and experimental approaches to determine how stochasticity and contingency shape the evolution of these host-beneficial relationships. This integrative approach should yield important new insights into the origins of symbiosis, the molecular processes of symbiont genome degeneration, and the coevolutionary mechanistic adaptations that take place between insects and their symbiotic bacteria.
This work is being done in collaboration with Colin Dale also in the School of Biological Sciences at the University of Utah (Dale Lab website -here) and Kevin P. Johnson at the University of Illinois Champaign-Urbana, Prarie Institute (Johnson lab website - here )
Please note that the PDFs are for personal use only, definitive versions are available from the publishers.
Smith, W. A., K. P. Johnson, D. L. Reed, T. Carter, K. L. Smith, R. Koga, T. Fukatsu, D. H. Clayton and C. Dale. 2013. Phylogenetic analysis of symbionts in feather-feeding lice of the genus Columbicola: Evidence for repeated symbiont replacements. BMC Evolutionary Biology 13:109-23. PDF
Fukatsu, T., R. Koga, W. A. Smith, K. Tanaka, N. Nikoh, K. Sasaki-Fukatsu, K. Yoshizawa, C. Dale, and D. H. Clayton. 2007. Bacterial endosymbiont of the slender pigeon louse Columbicola columbae allied to endosymbionts of grain weevils and tsetse flies. Applied and Environmental Microbiology 73: 6660-6668. PDF