When Does a Population Become a Species? - Johanna Beam
I would be remiss if I didn’t mention the beginning, albeit gloomier and more science lacking, per se, than the present. My college career didn’t start in Colorado, unlike many of my other peers. It began in the art studios of St. Olaf College in Northfield, Minnesota. It began at the fifth desk to the right, covered in pencils, brushes, gouache, and… birds. I double majored in Studio Art and Biology, somehow feeding my love of birds through art instead of science. After my second year of studying, my science-needy self was wilting even as my art side was flourishing. I needed a change of atmosphere. I decided to come home to Colorado and dedicate my last two years of undergrad to birds. I started the semester in the lab of Dr. Scott Taylor, where I proposed my honors thesis of meadowlark genomics and analysis. I wanted to study a particular population of Eastern Meadowlarks in the desert southwest of the United States called Lilian’s Eastern Meadowlark. I was particularly fascinated with the genetic (and thus taxonomic) status of this population because it appeared to have little or no gene flow with its ‘parent’ population of Eastern Meadowlarks, and like all Eastern Meadowlarks, seemed to be declining at an alarming rate.
Earlier research completed by Dr. Keith Barker of the Univ. of Minnesota suggested that Lilian’s be granted full species status based on mitochondrial markers and phylogenetic trees. My research was superficially similar to Dr. Barker’s, but mine would use whole genomes and include vocalization analysis. The American Ornithological Society had noted that they wanted to see more genetic and vocalization work done before they split Lilian’s into its own species. I received an Undergraduate Research Opportunities Program grant to complete my work and took a trip down to Arizona, New Mexico, and Texas to record these birds. My work has continued through all of senior year as I devote my time and energy to this special population of birds whose numbers are rapidly declining. In the time between now and my defense date, many questions keep ticking in and out of my head. The most important one, however, is as such: when does a population become a species?