Investigators with the USC Wrigley Institute of Environmental Studies have recently begun exploring research questions on the genetics and evolution of the endangered Channel Island fox, which lives exclusively on six of the eight Channel Islands off the coast of southern California. The scientists have teamed up with other research groups around the country using genetic information and chemical analyses to explore such questions as the evolution of the species, genetics across different island populations, and disease resistance.
The USC team will work with collaborators to achieve four primary goals: 1) to better estimate the timing of island fox arrival to the different Channel Islands; 2) to assess early 20th century fox genetics by extracting DNA from the Natural History Museum of Los Angeles’ historic (1930-40s) collections; 3) to attempt to extract ancient DNAs from island fox fossils and study the evolution of dwarfism in the species; and, 4) to analyze fox fecal samples and compare diets across the different islands, to better understand how the foxes may be impacted by food competitors like feral cats and spotted skunks.
USC researchers will focus in particular on Goal 2, as the nearby Natural History Museum’s collections provide a unique resource. Comparing historic genetic data to more modern data from different time points over the last century will allow the researchers to see how genetics of the species have changed over time, and particularly how foxes have been impacted by reductions in population size caused by canine distemper, golden eagle predation and habitat loss.
The biggest wild card may be the subsection of Goal 3 involving extraction of ancient DNA from fossils. The Natural History Museum and its sister museum the La Brea Tar Pits have a moderate number of fossils, but no one has yet succeeded in obtaining usable DNA from fox fossils. However, ancient DNA techniques are rapidly evolving and breakthroughs have been achieved in well-known species such as Neanderthals and woolly mammoths. If ancient fox DNA can be extracted, then that genetic information could be combined with studies of skeletons and ancient diets to yield additional insights into the species.
The convergence of scientific interest in island foxes by several research groups is unsurprising given recent advances in our ability to study the genetics of non-model organisms, combined with the inherent attraction of this charismatic endangered species. Merging the unique talents of researchers at the USC Wrigley Institute with the collective efforts of other researchers across the country should yield increasingly rapid and definitive answers to these types of urgent questions in island fox conservation.