Bioindicator snake shows genomic signatures of natural and anthropogenic barriers to gene flow
Urbanisation alters landscapes, introduces wildlife to novel stressors, and fragments habitats into remnant ‘islands’. Within these islands, isolated wildlife populations can experience genetic drift and subsequently suffer from inbreeding depression and reduced adaptive potential. The Western tiger...
| Main Authors: | , , , , , , |
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| Format: | Journal Article |
| Language: | English |
| Published: |
2021
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| Subjects: | |
| Online Access: | http://purl.org/au-research/grants/arc/ LP160100189 http://hdl.handle.net/20.500.11937/87412 |
| _version_ | 1848764918001565696 |
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| author | Lettoof, Damian Thomson, V.A. Cornelis, Jari Bateman, Bill Aubret, Fabien Gagnon, Monique von Takach, Brenton |
| author_facet | Lettoof, Damian Thomson, V.A. Cornelis, Jari Bateman, Bill Aubret, Fabien Gagnon, Monique von Takach, Brenton |
| author_sort | Lettoof, Damian |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Urbanisation alters landscapes, introduces wildlife to novel stressors, and fragments habitats into remnant ‘islands’. Within these islands, isolated wildlife populations can experience genetic drift and subsequently suffer from inbreeding depression and reduced adaptive potential. The Western tiger snake (Notechis scutatus occidentalis) is a predator of wetlands in the Swan Coastal Plain, a unique bioregion that has suffered substantial degradation through the development of the city of Perth, Western Australia. Within the urban matrix, tiger snakes now only persist in a handful of wetlands where they are known to bioaccumulate a suite of contaminants, and have recently been suggested as a relevant bioindicator of ecosystem health. Here, we used genome-wide single nucleotide polymorphism (SNP) data to explore the contemporary population genomics of seven tiger snake populations across the urban matrix. Specifically, we used population genomic structure and diversity, effective population sizes (Ne), and heterozygosity-fitness correlations to assess fitness of each population with respect to urbanisation. We found that population genomic structure was strongest across the northern and southern sides of a major river system, with the northern cluster of populations exhibiting lower heterozygosities than the southern cluster, likely due to a lack of historical gene flow. We also observed an increasing signal of inbreeding and genetic drift with increasing geographic isolation due to urbanisation. Effective population sizes (Ne) at most sites were small (< 100), with Ne appearing to reflect the area of available habitat rather than the degree of adjacent urbanisation. This suggests that ecosystem management and restoration may be the best method to buffer the further loss of genetic diversity in urban wetlands. If tiger snake populations continue to decline in urban areas, our results provide a baseline measure of genomic diversity, as well as highlighting which ‘islands’ of habitat are most in need of management and protection. |
| first_indexed | 2025-11-14T11:26:59Z |
| format | Journal Article |
| id | curtin-20.500.11937-87412 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | eng |
| last_indexed | 2025-11-14T11:26:59Z |
| publishDate | 2021 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-874122022-02-03T09:08:00Z Bioindicator snake shows genomic signatures of natural and anthropogenic barriers to gene flow Lettoof, Damian Thomson, V.A. Cornelis, Jari Bateman, Bill Aubret, Fabien Gagnon, Monique von Takach, Brenton Animals Conservation of Natural Resources Elapidae Environmental Biomarkers Genetic Drift Genetic Variation Genetics, Population Western Australia Wetlands Urbanisation alters landscapes, introduces wildlife to novel stressors, and fragments habitats into remnant ‘islands’. Within these islands, isolated wildlife populations can experience genetic drift and subsequently suffer from inbreeding depression and reduced adaptive potential. The Western tiger snake (Notechis scutatus occidentalis) is a predator of wetlands in the Swan Coastal Plain, a unique bioregion that has suffered substantial degradation through the development of the city of Perth, Western Australia. Within the urban matrix, tiger snakes now only persist in a handful of wetlands where they are known to bioaccumulate a suite of contaminants, and have recently been suggested as a relevant bioindicator of ecosystem health. Here, we used genome-wide single nucleotide polymorphism (SNP) data to explore the contemporary population genomics of seven tiger snake populations across the urban matrix. Specifically, we used population genomic structure and diversity, effective population sizes (Ne), and heterozygosity-fitness correlations to assess fitness of each population with respect to urbanisation. We found that population genomic structure was strongest across the northern and southern sides of a major river system, with the northern cluster of populations exhibiting lower heterozygosities than the southern cluster, likely due to a lack of historical gene flow. We also observed an increasing signal of inbreeding and genetic drift with increasing geographic isolation due to urbanisation. Effective population sizes (Ne) at most sites were small (< 100), with Ne appearing to reflect the area of available habitat rather than the degree of adjacent urbanisation. This suggests that ecosystem management and restoration may be the best method to buffer the further loss of genetic diversity in urban wetlands. If tiger snake populations continue to decline in urban areas, our results provide a baseline measure of genomic diversity, as well as highlighting which ‘islands’ of habitat are most in need of management and protection. 2021 Journal Article http://hdl.handle.net/20.500.11937/87412 10.1371/journal.pone.0259124 eng http://purl.org/au-research/grants/arc/ LP160100189 http://purl.org/au-research/grants/arc/DE180100624 http://creativecommons.org/licenses/by/4.0/ fulltext |
| spellingShingle | Animals Conservation of Natural Resources Elapidae Environmental Biomarkers Genetic Drift Genetic Variation Genetics, Population Western Australia Wetlands Lettoof, Damian Thomson, V.A. Cornelis, Jari Bateman, Bill Aubret, Fabien Gagnon, Monique von Takach, Brenton Bioindicator snake shows genomic signatures of natural and anthropogenic barriers to gene flow |
| title | Bioindicator snake shows genomic signatures of natural and anthropogenic barriers to gene flow |
| title_full | Bioindicator snake shows genomic signatures of natural and anthropogenic barriers to gene flow |
| title_fullStr | Bioindicator snake shows genomic signatures of natural and anthropogenic barriers to gene flow |
| title_full_unstemmed | Bioindicator snake shows genomic signatures of natural and anthropogenic barriers to gene flow |
| title_short | Bioindicator snake shows genomic signatures of natural and anthropogenic barriers to gene flow |
| title_sort | bioindicator snake shows genomic signatures of natural and anthropogenic barriers to gene flow |
| topic | Animals Conservation of Natural Resources Elapidae Environmental Biomarkers Genetic Drift Genetic Variation Genetics, Population Western Australia Wetlands |
| url | http://purl.org/au-research/grants/arc/ LP160100189 http://purl.org/au-research/grants/arc/ LP160100189 http://hdl.handle.net/20.500.11937/87412 |