Abstract Detail

Population Genetics/Genomics

Cantley, Jason [1], Bullock, Madison [2], Williams, Tanisha [3], Haase, Butch [4], Martine, Chris [3].

Exploring evolutionary processes promoting adaptive divergence across populations of Hawaiian Chenopodium oahuense (Amaranthaceae).

The widespread Hawaiian taxon Chenopodium oahuense (Amaranthaceae) is morphologically variable and some isolated populations appear to be in the early stages of adaptive divergence. Today, while the two subspecies of the taxon are allopatric in their distribution, one population is morphologically intermediate and occurs at a geographically and climatically intermediate location—the seacliffs of Pu‘u Ka Pele, Moloka‘i. Initially, it was hypothesized that this population could represent clinal variation due to incomplete lineage sorting. However, a recent herbarium investigation revealed that as recently as the 1970s, individuals will strong morphological affinities to the widespread subspecies were collected in the adjacently located Ho‘olehua Dump—a now defunct landfill. This new realization opened the possibility that the Pu‘u Ka Pele population could represent a recent human-facilitated subspecific hybridization since vehicular traffic could have brought this occasionally ruderal behaving species from other locations on the island. Preliminary population genetic analyses indicate that there is subspecific genetic structure and that the Pu‘u Ka Pele population is an admixture of both. Further results will be discussed to provide clarity on the important evolutionary factors promoting what appears to be incipient adaptive divergence in this interesting lineage.

1 - San Francisco State University, 1600 Holloway Ave, SF State University Biology Department, Hensill Hall, 1751 Market Street APT 4, SF State University Biology Department, Hensill Ha, San Francisco, CA, 94103, United States
2 - Texas Tech University, Biological Sciences, 2901 Main Street, Lubbock, TX, 79409, United States
3 - Bucknell University, Biology, 1 Dent Drive, Lewisburg, PA, 17837, United States
4 - Molokai Land Trust, Hawaii

Keywords:
hybridization
adaptation
population genetics
Hawaii
Incomplete Lineage Sorting.

Presentation Type: Oral Paper
Number: PGG4003
Abstract ID:1040
Candidate for Awards:Margaret Menzel Award