Ancient DNA
Ancient DNA (DNA isolated from things long dead such as subfossil bones, mummies or museum specimens) methods are extremely useful in studies of conservation and evolutionary genetics. Careful application of these methods has enabled Center for Conservation Genomics researchers to estimate the levels and patterns of genetic variation in a species even thousands of years ago, and how this variation has changed over time.
Scientists use this information to determine whether low genetic variation in a species was caused by recent human-influenced declines in population size, or from declines that occurred in the more distant past (in, for example, the Hawaiian goose or nene and the Hawaiian petrel). Scientists can also use ancient DNA analysis to reconstruct evolutionary relationships of extinct and endangered animals, allowing them to better define species and populations and their evolutionary uniqueness.
Using these methods, CCG scientists found that the five honeyeater species that once lived in Hawaii (one until the 1980s) are not the same as Australian honeyeaters, but are a unique family of Hawaiian birds related most closely to waxwings and silky flycatchers. Convergent evolution because of similar foraging habits caused the deceptive similarity.
Ancient DNA methods have also proven very useful for studies of wildlife disease. They can allow scientists to determine when invasive pathogens colonized native host populations, genetic changes in introduced vectors, and even to assess coevolution that can occur between host and parasite.
CCG researchers have been leaders in the application of ancient DNA methods to issues in conservation and evolutionary biology. Notable studies involve extinct and endangered Hawaiian honeycreepers, black-footed ferrets, quaggas, Indian wolves, ivory-billed woodpeckers and a new species of forest robin from Gabon.
