Presenter(s): Connor Lane—Biology
Faculty Mentor(s): Matt Streisfeld
Session 4: Preserving Mother Earth
One of the main goals of evolutionary biology and ecology is to understand the mechanisms by which the vast diversity in life on Earth is created . Integral to this process is speciation, where one species diverges into two . Recent work has shown that speciation can occur even if populations are not completely isolated with each other, which is known as speciation with gene flow . To understand this phenomenon, we perform a survey characterizing genetic admixture and genomic ancestry in Mimulus aurantiacus ssp . puniceus . From here, we test whether or not certain genome features thought to be indicative of local adaptation covary with geographic space and environmental differences . We hypothesize that due to local adaptation being well-characterized within ssp . puniceus, we will observe substantial genetic subdivision in our survey and find that important genome statistics covary with environment due to adaptation leading to genetic isolation . From our survey, we found both an extraordinary amount of genetic subdivision in ssp . puniceus, indicating that what we consider to be one subspecies has many distinct groups . In addition to this, we find that the most differentiated groups within puniceus have indistinguishable floral trait distributions, hinting at a deeper history of isolation rather than these groups being separated due to natural selection . Population genomic data reveals that variation in genome features signaling divergence is explained by variation in both geography and environment, implying that both neutral processes based on geographic isolation and positive selection due to local ecology are important for shaping the genome .