Abstract Detail

Molecular Ecology

Diaz-Martin, Zoe [1], Cisternas, Anita [2], Skogen, Krissa [3], Kay, Kathleen [4], Raguso, Robert [5], Fant, Jeremie [6].

Differences in gene flow between progenitor-derivative taxa reflect pollination mode and mating system.

Recent, rapid diversification in angiosperms has resulted in many progenitor-derivative species pairs, whereby reproductive isolation in the derivatives arises through a shift to a predominantly selfing mating system or a shift primary pollinator. While these types of shifts are common, the way in which they alter the patterns and consequences of gene flow remain understudied. We use three taxa within the evening primrose family (Onagraceae), Clarkia concinna subsp. concinna (progenitor, pollinated by bees and flies), Clarkia concinna subsp. automixa (derivative, selfing), and Clarkia breweri (derivative, pollinated by hawkmoths) to explore how shifts to predominantly selfing and between pollinator groups shape contemporary patterns of genetic diversity, structure, and inbreeding between taxa using population genomic tools. We found little to no gene flow between the progenitor and the derived taxa or between the derived taxa. Contrary to expectations, C. breweri had lower genetic diversity than C. concinna subsp. concinna and C. concinna subsp. automixa, the latter of which had the highest level of genetic diversity. In addition, C. breweri had comparable levels of genetic structure and inbreeding as the two other species. However, we did observe significant isolation by distance for C. breweri but not for C. concinna subsp. concinna. Similarly, we found a positive association between inbreeding and distance to the ten nearest sites for C. breweri and not C. concinna subsp. concinna. High negative inbreeding in the selfing C. concinna subsp. automixa suggest that  it has experienced chromosomal translocations commonly observed in other Clarkia species. In addition, we propose that while C. breweri has not yet recovered from the initial bottleneck after speciation, hawkmoths still facilitate high rates of gene flow between populations.  

1 - Chicago Botanic Garden, Plant Science and Conservation, 1000 Lake Cook Road, Glencoe, IL, 60022, United States
2 - 1009 Davis St. Apt 28, Evanston, IL, 60201, United States
3 - Chicago Botanic Garden, Conservation Scientist, 1000 Lake Cook Road, Glencoe, IL, 60022, United States
4 - UC Santa Cruz, Ecology And Evolutionary Biology, 130 McAllister Way, Coastal Biology Building, Santa Cruz, CA, 95060, United States
5 - Cornell University, Dept. Of Neurobiology And Behavior, W355 Mudd Hall, 215 Tower Road, Ithaca, NY, 14853, United States
6 - Chicago Botanic Gardens, Plant Biology And Conservation , 1000 Lake Cook Rd, Glencoe, IL, 60022, United States

Keywords:
evolutionary ecology
pollination
gene flow
genetic diversity.

Presentation Type: Oral Paper
Session: ME1, Molecular Ecology
Location: /
Date: Tuesday, July 20th, 2021
Time: 4:00 PM(EDT)
Number: ME1005
Abstract ID:883
Candidate for Awards:None