Abstract Detail


Antoine, Ariel [1], Williams, Tanisha [2], McDonnell, Angela [3], Cantley, Jason [4], Jobson, Peter [5], Martine, Christopher [6].

Biogeographic barrier testing methods suggest genetic differentiation within a morphologically-stable species of the Australian Monsoon Tropics.

The Australian Monsoon Tropics (AMT) is a biodiversity hotspot with large numbers of endemic plants and animals. The AMT is a vast region known for its dry harsh environment throughout much of the year with the inundation of rainfall during the months of the Austral winter. Over the past three million years, the AMT has undergone climate fluctuations due to cooling and drying patterns that contributed to the development of seven geographic barriers across the AMT. In studies of other plant species, these barriers created patterns of geographic isolation and morphologic distinctiveness, causing populations to adapt and speciate. However, this is not the case with Templetonia hookeri (Fabaceae), a species distributed across the AMT that is  morphologically stable across biogeographic barriers. Biogeographic barrier testing methods were used subsequent to population genetics analyses to assess whether the  barriers influenced the distribution pattern observed. Population genetics revealed that the nine populations observed were genetically isolated,  show low levels of genetic diversity, exhibit high levels of inbreeding, and are structured by geography. Of the biogeographic barrier testing methods, isolation by distance determined that the correlation between geographic distance and genetic distance of the individuals was significant, and gene flow between populations was limited.  Isolation by barrier testing indicated that there was significant differentiation and variation among populations separated by putative biogeographic barriers. Furthermore, the significant population structure coupled with high levels of inbreeding indicate that the biogeographic barriers are true barriers restricting gene flow across populations of T. hookeri - despite a lack of observed morphological variation across the range of the species. 

1 - Bucknell University , Biology, 1 Dent Drive, Lewisburg, PA, 17837, USA
2 - Bucknell University, Biology, 1 Dent Drive, Lewisburg, Pennsylvania, 17837, United States
3 - Chicago Botanic Garden, Science Dept., 1000 Lake Cook Road, Glencoe, IL, 60022, United States
4 - San Francisco State University, Biology, 1600 Holloway Ave, SF State University Biology Department, Hensill Ha, San Francisco, CA, 94132, United States
5 - Northern Territory Herbarium, Alice Springs, NT, AU
6 - Bucknell University, Biological Sciences, 203 Biology Building, Lewisburg, PA, 17837, United States

Australian Monsoon Tropics
biogeographic barriers
gene flow
population structure

Presentation Type: Poster
Session: P, Ecology Posters
Location: Virtual/Virtual
Date: Tuesday, July 28th, 2020
Time: 5:00 PM Time and date to be determined
Number: PEC005
Abstract ID:395
Candidate for Awards:None

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