Restricted geographic distribution and low genetic diversity of the brooding sea urchin Abatus agassizii (Spatangoidea: Schizasteridae) in the South Shetland Islands: A bridgehead population before the spread to the northern Antarctic Peninsula?

The glacial cycles of the Pleistocene have promoted the principal climatic changes of the Southern Ocean, and motivated scientific interest regarding the strategies developed by marine benthic invertebrates to tolerate and overcome the extension and contraction of the ice sheet on the Antarctic cont...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	DÍAZ,ANGIE, GONZÁLEZ-WEVAR,CLAUDIO ALEJANDRO, MATURANA,CLAUDIA S, PALMA,ALVARO T, POULIN,ELIE, GERARD,KARIN
Lenguaje:	English
Publicado:	Sociedad de Biología de Chile 2012
Materias:	Antarctic benthic fauna COI phylogenetic relationships King George Island Southern Ocean survivor population
Acceso en línea:	http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2012000400008
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:scielo:S0716-078X2012000400008
record_format	dspace
spelling	oai:scielo:S0716-078X20120004000082013-07-26Restricted geographic distribution and low genetic diversity of the brooding sea urchin Abatus agassizii (Spatangoidea: Schizasteridae) in the South Shetland Islands: A bridgehead population before the spread to the northern Antarctic Peninsula?DÍAZ,ANGIEGONZÁLEZ-WEVAR,CLAUDIO ALEJANDROMATURANA,CLAUDIA SPALMA,ALVARO TPOULIN,ELIEGERARD,KARIN Antarctic benthic fauna COI phylogenetic relationships King George Island Southern Ocean survivor population The glacial cycles of the Pleistocene have promoted the principal climatic changes of the Southern Ocean, and motivated scientific interest regarding the strategies developed by marine benthic invertebrates to tolerate and overcome the extension and contraction of the ice sheet on the Antarctic continental platform. A recent study of the bathymetric zonation and distribution of macro-invertebrates in a shallow subtidal area of Fildes Bay (King George Island, South Shetlands Islands, Antarctica) highlighted the presence of a large aggregation of the brooding sea urchin Abatus agassizii, whose geographic distribution is known only for localities south of the Antarctic convergence (Antarctic Peninsula and South Shetland and South Georgia Islands in the Scotia Arc). Its presence is atypical, given that these shallow populations should have been erased from the vicinity of the Antarctic Peninsula by the advances and retreats of the ice sheet, and the absence of a larval stage associated with brooding should limit re-colonization from northern Subantarctic areas. The aim of the study was to evaluate whether A. agassizii may have survived the glaciations in its narrow bathymetric range in the South Shetland Islands, or whether this population corresponds to a newcomer that re-colonized the area despite its low dispersal capacities. For this, we combined multidisciplinary approaches based on the geographical distribution of A. agassizii, its genetic diversity and its phylogenetic relationships with other species of the genus. In spite of an intensive sampling effort, the low occurrence of A. agassizii indicated that its distribution is very scarce along the Shetlands Islands and the Antarctic Peninsula, and seems to be restricted to protected and ice-free areas of Fildes Bay in King George Island. Moreover, this population presented very low genetic diversity associated with the signal of a recent demographic expansion. Finally, the reconstruction of the phylogenetic relationships among species of Abatus using mitochondrial COI sequences established the affinity of the Antarctic A. agassizii with Subantarctic species. Based on these results we consider that the presence of this species in the Shetland Islands more likely corresponds to a recent re-colonization from Antarctic Islands located further north.info:eu-repo/semantics/openAccessSociedad de Biología de ChileRevista chilena de historia natural v.85 n.4 20122012-12-01text/htmlhttp://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2012000400008en10.4067/S0716-078X2012000400008
institution	Scielo Chile
collection	Scielo Chile
language	English
topic	Antarctic benthic fauna COI phylogenetic relationships King George Island Southern Ocean survivor population
spellingShingle	Antarctic benthic fauna COI phylogenetic relationships King George Island Southern Ocean survivor population DÍAZ,ANGIE GONZÁLEZ-WEVAR,CLAUDIO ALEJANDRO MATURANA,CLAUDIA S PALMA,ALVARO T POULIN,ELIE GERARD,KARIN Restricted geographic distribution and low genetic diversity of the brooding sea urchin Abatus agassizii (Spatangoidea: Schizasteridae) in the South Shetland Islands: A bridgehead population before the spread to the northern Antarctic Peninsula?
description	The glacial cycles of the Pleistocene have promoted the principal climatic changes of the Southern Ocean, and motivated scientific interest regarding the strategies developed by marine benthic invertebrates to tolerate and overcome the extension and contraction of the ice sheet on the Antarctic continental platform. A recent study of the bathymetric zonation and distribution of macro-invertebrates in a shallow subtidal area of Fildes Bay (King George Island, South Shetlands Islands, Antarctica) highlighted the presence of a large aggregation of the brooding sea urchin Abatus agassizii, whose geographic distribution is known only for localities south of the Antarctic convergence (Antarctic Peninsula and South Shetland and South Georgia Islands in the Scotia Arc). Its presence is atypical, given that these shallow populations should have been erased from the vicinity of the Antarctic Peninsula by the advances and retreats of the ice sheet, and the absence of a larval stage associated with brooding should limit re-colonization from northern Subantarctic areas. The aim of the study was to evaluate whether A. agassizii may have survived the glaciations in its narrow bathymetric range in the South Shetland Islands, or whether this population corresponds to a newcomer that re-colonized the area despite its low dispersal capacities. For this, we combined multidisciplinary approaches based on the geographical distribution of A. agassizii, its genetic diversity and its phylogenetic relationships with other species of the genus. In spite of an intensive sampling effort, the low occurrence of A. agassizii indicated that its distribution is very scarce along the Shetlands Islands and the Antarctic Peninsula, and seems to be restricted to protected and ice-free areas of Fildes Bay in King George Island. Moreover, this population presented very low genetic diversity associated with the signal of a recent demographic expansion. Finally, the reconstruction of the phylogenetic relationships among species of Abatus using mitochondrial COI sequences established the affinity of the Antarctic A. agassizii with Subantarctic species. Based on these results we consider that the presence of this species in the Shetland Islands more likely corresponds to a recent re-colonization from Antarctic Islands located further north.
author	DÍAZ,ANGIE GONZÁLEZ-WEVAR,CLAUDIO ALEJANDRO MATURANA,CLAUDIA S PALMA,ALVARO T POULIN,ELIE GERARD,KARIN
author_facet	DÍAZ,ANGIE GONZÁLEZ-WEVAR,CLAUDIO ALEJANDRO MATURANA,CLAUDIA S PALMA,ALVARO T POULIN,ELIE GERARD,KARIN
author_sort	DÍAZ,ANGIE
title	Restricted geographic distribution and low genetic diversity of the brooding sea urchin Abatus agassizii (Spatangoidea: Schizasteridae) in the South Shetland Islands: A bridgehead population before the spread to the northern Antarctic Peninsula?
title_short	Restricted geographic distribution and low genetic diversity of the brooding sea urchin Abatus agassizii (Spatangoidea: Schizasteridae) in the South Shetland Islands: A bridgehead population before the spread to the northern Antarctic Peninsula?
title_full	Restricted geographic distribution and low genetic diversity of the brooding sea urchin Abatus agassizii (Spatangoidea: Schizasteridae) in the South Shetland Islands: A bridgehead population before the spread to the northern Antarctic Peninsula?
title_fullStr	Restricted geographic distribution and low genetic diversity of the brooding sea urchin Abatus agassizii (Spatangoidea: Schizasteridae) in the South Shetland Islands: A bridgehead population before the spread to the northern Antarctic Peninsula?
title_full_unstemmed	Restricted geographic distribution and low genetic diversity of the brooding sea urchin Abatus agassizii (Spatangoidea: Schizasteridae) in the South Shetland Islands: A bridgehead population before the spread to the northern Antarctic Peninsula?
title_sort	restricted geographic distribution and low genetic diversity of the brooding sea urchin abatus agassizii (spatangoidea: schizasteridae) in the south shetland islands: a bridgehead population before the spread to the northern antarctic peninsula?
publisher	Sociedad de Biología de Chile
publishDate	2012
url	http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2012000400008
work_keys_str_mv	AT diazangie restrictedgeographicdistributionandlowgeneticdiversityofthebroodingseaurchinabatusagassiziispatangoideaschizasteridaeinthesouthshetlandislandsabridgeheadpopulationbeforethespreadtothenorthernantarcticpeninsula AT gonzalezwevarclaudioalejandro restrictedgeographicdistributionandlowgeneticdiversityofthebroodingseaurchinabatusagassiziispatangoideaschizasteridaeinthesouthshetlandislandsabridgeheadpopulationbeforethespreadtothenorthernantarcticpeninsula AT maturanaclaudias restrictedgeographicdistributionandlowgeneticdiversityofthebroodingseaurchinabatusagassiziispatangoideaschizasteridaeinthesouthshetlandislandsabridgeheadpopulationbeforethespreadtothenorthernantarcticpeninsula AT palmaalvarot restrictedgeographicdistributionandlowgeneticdiversityofthebroodingseaurchinabatusagassiziispatangoideaschizasteridaeinthesouthshetlandislandsabridgeheadpopulationbeforethespreadtothenorthernantarcticpeninsula AT poulinelie restrictedgeographicdistributionandlowgeneticdiversityofthebroodingseaurchinabatusagassiziispatangoideaschizasteridaeinthesouthshetlandislandsabridgeheadpopulationbeforethespreadtothenorthernantarcticpeninsula AT gerardkarin restrictedgeographicdistributionandlowgeneticdiversityofthebroodingseaurchinabatusagassiziispatangoideaschizasteridaeinthesouthshetlandislandsabridgeheadpopulationbeforethespreadtothenorthernantarcticpeninsula
_version_	1718439672912281600

Restricted geographic distribution and low genetic diversity of the brooding sea urchin Abatus agassizii (Spatangoidea: Schizasteridae) in the South Shetland Islands: A bridgehead population before the spread to the northern Antarctic Peninsula?

Ejemplares similares