COLLEGE STATION, Nov. 1, 2007 – Researchers at Texas A&M University’s College of Veterinary Medicine & Biomedical Sciences, in collaboration with scientists representing institutions around the world, have discovered the closest living relative to primates. They did so after completing a multispecies genomic comparison within the superordinal group Euarchonta, which includes primates, dermoptera (colugos) and scandentia (tree shrews). Their findings are published in the Nov. 2 edition of the journal Science.
“Determination of the closest living relative of primates has important ramifications for anthropology and genomics,” said Dr. William Murphy, a professor of veterinary integrative biosciences and team leader of the study.“In order to resolve the ancestral relationships among primates and their closest relatives, we had to compare alignments in recently sequenced genomes of multiple species, looking for rare genomic changes which would suggest evolutionary branching patterns between species. This gives us a clearer, more accurate look at how primates evolved and may help in placing fossil primates and their relatives on the evolutionary family tree.”
As conclusions of the study have indicated that colugos (flying lemurs), rather than tree shrews, are genetically more closely related to primates, further sequencing of the colugo genome is warranted, Murphy said, in order to develop a better understanding of the evolutionary changes leading to primates, as well as to more accurately reconstruct the ancestral primate genome.
According to Murphy, the origins of primates and primates found in the fossil record have been a topic of intense debate as there has been an increased focus on identifying adaptive evolutionary changes with primates. By decoding the past through changes in genomics, a clearer picture of the evolution of primates emerges that will provide a broader context for future research, he said.
The multidisciplinary approach to the genomic comparisons utilized in this study also revealed additional information that will prove beneficial to global biodiversity, Murphy added.
“In addition to identifying colugos as the closest living relative to primates, we were able to make some very important discoveries about the tree shrews,” said Murphy. “The phylogenetic uniqueness we documented in Ptilocercus, coupled with its restriction to a lowland forest habitat and limited global range, have certainly identified it as an important conservation effort in a global sense.”
The study was funded by grants from the National Science Foundation and the National Institutes of Health. The paper was led by post-doctoral researcher Jan Janecka of Texas A&M University, and involved specialists in bioinformatics and mammalogy from several institutions, including Dr. Webb Miller from Penn State University, Dr. Thomas Pringle of the Sperling Foundation, Dr. Mark Springer of the University of California at Riverside, Dr. Kristofer Helgen of the Smithsonian Institution, and Drs. Annette Zitzmann and Frank Wiens of the Johann Wolfgang Goethe-University and the University of Bayreuth, respectively.
Journal
Science