Historical dynamics of Leopard Seal (Hydrurga leptonyx) and Southern Elephant Seal (Mirounga leonina) populations in the Southern Ocean
The history of the Pinnipeds living in Antarctic waters has been shaped by periods of climatic changes and anthropogenic impact which have affected their population dynamics. In this study, molecular genetic data were used to test hypotheses about the impact of environmental change and the mechanism...
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ftunidurhamethes:oai:etheses.dur.ac.uk:12483 2023-05-15T14:04:17+02:00 Historical dynamics of Leopard Seal (Hydrurga leptonyx) and Southern Elephant Seal (Mirounga leonina) populations in the Southern Ocean BONILLAS-MONGE, MARIO,ERANDI 2018 application/pdf http://etheses.dur.ac.uk/12483/ http://etheses.dur.ac.uk/12483/1/Msc_Thesis_ME_Bonillas.pdf unknown oai:etheses.dur.ac.uk:12483 http://etheses.dur.ac.uk/12483/1/Msc_Thesis_ME_Bonillas.pdf BONILLAS-MONGE, MARIO,ERANDI (2018) Historical dynamics of Leopard Seal (Hydrurga leptonyx) and Southern Elephant Seal (Mirounga leonina) populations in the Southern Ocean. Masters thesis, Durham University. http://etheses.dur.ac.uk/12483/ Genetics DNA Elephant Seal Leopard Seal Thesis NonPeerReviewed 2018 ftunidurhamethes 2022-09-23T14:16:59Z The history of the Pinnipeds living in Antarctic waters has been shaped by periods of climatic changes and anthropogenic impact which have affected their population dynamics. In this study, molecular genetic data were used to test hypotheses about the impact of environmental change and the mechanisms generating changes in the population dynamics of two Southern Ocean Pinniped species. The genetic diversity of contemporary Southern Elephant Seal populations was investigated in order to assess the demographic history and the degree of connectivity between the only continental colony and the three closest island colonies. For Leopard Seals, ancient DNA in comparison with modern samples provided even greater resolution on how the dynamics of a population changed in the Antarctic region through time and how this could be related to climate change. The Leopard Seal data provided an estimate of the whole mitochondrial genome mutation rate that was higher than previous phylogenetic estimates, but consistent with other estimates incorporating ancient DNA (including that calculated earlier for the Southern Elephant Seal). The Leopard Seal showed an expansion that occurred from 7,500 to 2,500 YBP, overlapping with two major periods of climatic change. For the Southern Elephant Seal, all sub-Antarctic island colonies could be considered as a single population, whereas the mainland population (the Argentinean colony) was genetically differentiated from the island colonies and had a significantly lower effective population size. The divergence of the continental colony from the island colonies occurred during the Holocene. Each species showed transitional changes during the Holocene, but while the Leopard Seal population expanded, the Southern Elephant Seal populations diverged, founding a new colony on the mainland. The broader implications for understanding historical biogeography in marine systems are discussed. Thesis Antarc* Antarctic Elephant Seal Hydrurga leptonyx Leopard Seal Leopard Seals Mirounga leonina Southern Elephant Seal Southern Ocean Durham University: Durham e-Theses Antarctic Hydrurga ENVELOPE(-61.626,-61.626,-64.145,-64.145) Southern Ocean The Antarctic |
institution |
Open Polar |
collection |
Durham University: Durham e-Theses |
op_collection_id |
ftunidurhamethes |
language |
unknown |
topic |
Genetics DNA Elephant Seal Leopard Seal |
spellingShingle |
Genetics DNA Elephant Seal Leopard Seal BONILLAS-MONGE, MARIO,ERANDI Historical dynamics of Leopard Seal (Hydrurga leptonyx) and Southern Elephant Seal (Mirounga leonina) populations in the Southern Ocean |
topic_facet |
Genetics DNA Elephant Seal Leopard Seal |
description |
The history of the Pinnipeds living in Antarctic waters has been shaped by periods of climatic changes and anthropogenic impact which have affected their population dynamics. In this study, molecular genetic data were used to test hypotheses about the impact of environmental change and the mechanisms generating changes in the population dynamics of two Southern Ocean Pinniped species. The genetic diversity of contemporary Southern Elephant Seal populations was investigated in order to assess the demographic history and the degree of connectivity between the only continental colony and the three closest island colonies. For Leopard Seals, ancient DNA in comparison with modern samples provided even greater resolution on how the dynamics of a population changed in the Antarctic region through time and how this could be related to climate change. The Leopard Seal data provided an estimate of the whole mitochondrial genome mutation rate that was higher than previous phylogenetic estimates, but consistent with other estimates incorporating ancient DNA (including that calculated earlier for the Southern Elephant Seal). The Leopard Seal showed an expansion that occurred from 7,500 to 2,500 YBP, overlapping with two major periods of climatic change. For the Southern Elephant Seal, all sub-Antarctic island colonies could be considered as a single population, whereas the mainland population (the Argentinean colony) was genetically differentiated from the island colonies and had a significantly lower effective population size. The divergence of the continental colony from the island colonies occurred during the Holocene. Each species showed transitional changes during the Holocene, but while the Leopard Seal population expanded, the Southern Elephant Seal populations diverged, founding a new colony on the mainland. The broader implications for understanding historical biogeography in marine systems are discussed. |
format |
Thesis |
author |
BONILLAS-MONGE, MARIO,ERANDI |
author_facet |
BONILLAS-MONGE, MARIO,ERANDI |
author_sort |
BONILLAS-MONGE, MARIO,ERANDI |
title |
Historical dynamics of Leopard Seal (Hydrurga leptonyx) and Southern Elephant Seal (Mirounga leonina) populations in the Southern Ocean |
title_short |
Historical dynamics of Leopard Seal (Hydrurga leptonyx) and Southern Elephant Seal (Mirounga leonina) populations in the Southern Ocean |
title_full |
Historical dynamics of Leopard Seal (Hydrurga leptonyx) and Southern Elephant Seal (Mirounga leonina) populations in the Southern Ocean |
title_fullStr |
Historical dynamics of Leopard Seal (Hydrurga leptonyx) and Southern Elephant Seal (Mirounga leonina) populations in the Southern Ocean |
title_full_unstemmed |
Historical dynamics of Leopard Seal (Hydrurga leptonyx) and Southern Elephant Seal (Mirounga leonina) populations in the Southern Ocean |
title_sort |
historical dynamics of leopard seal (hydrurga leptonyx) and southern elephant seal (mirounga leonina) populations in the southern ocean |
publishDate |
2018 |
url |
http://etheses.dur.ac.uk/12483/ http://etheses.dur.ac.uk/12483/1/Msc_Thesis_ME_Bonillas.pdf |
long_lat |
ENVELOPE(-61.626,-61.626,-64.145,-64.145) |
geographic |
Antarctic Hydrurga Southern Ocean The Antarctic |
geographic_facet |
Antarctic Hydrurga Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Elephant Seal Hydrurga leptonyx Leopard Seal Leopard Seals Mirounga leonina Southern Elephant Seal Southern Ocean |
genre_facet |
Antarc* Antarctic Elephant Seal Hydrurga leptonyx Leopard Seal Leopard Seals Mirounga leonina Southern Elephant Seal Southern Ocean |
op_relation |
oai:etheses.dur.ac.uk:12483 http://etheses.dur.ac.uk/12483/1/Msc_Thesis_ME_Bonillas.pdf BONILLAS-MONGE, MARIO,ERANDI (2018) Historical dynamics of Leopard Seal (Hydrurga leptonyx) and Southern Elephant Seal (Mirounga leonina) populations in the Southern Ocean. Masters thesis, Durham University. http://etheses.dur.ac.uk/12483/ |
_version_ |
1766275322611761152 |