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Spheniscidae (1 Viewer)
- Thread starter Richard Klim
- Start date
Daniel Philippe
Well-known member
Subramanian, S., G. Beans-Picón, S. K. Swaminathan, C. D. Millar & D. M. Lambert, 2013. Evidence for a recent origin of penguins. Biol. Lett. 9, 20130748.
access to pdf
access to pdf
Peter Kovalik
Well-known member
Peter Kovalik
Well-known member
Michiko Murata, Masaru Murakami, 2014. Two Distinct mtDNA Lineages among Captive African Penguins in Japan. Journal of Veterinary Medical Science, Vol. 76 No. 4 April p. 559-563.
Abstract:
The African penguin (Spheniscus demersus) is one of the world’s most endangered seabirds. In Japan, although the number of African penguins in captivity continues to increase, genetic data have not been collected for either wild or captive populations. To reveal genetic diversity and characterization in captive African penguins, we analyzed the nucleotide sequences of mitochondrial DNA (mtDNA) from a sample of 236 African penguins. Analysis of 433 bp of the control region and 1,140 bp of cytochrome b sequences revealed the existence of two mtDNA clades. Control region haplotypes were much more divergent (d=3.39%) between the two clades than within each clade. The divergence of these clades may reflect differences at the subspecies or geographical population level in African penguins. These findings suggest that at least two distinct maternal lineages exist in the wild populations of the African penguin.
[PDF]
Abstract:
The African penguin (Spheniscus demersus) is one of the world’s most endangered seabirds. In Japan, although the number of African penguins in captivity continues to increase, genetic data have not been collected for either wild or captive populations. To reveal genetic diversity and characterization in captive African penguins, we analyzed the nucleotide sequences of mitochondrial DNA (mtDNA) from a sample of 236 African penguins. Analysis of 433 bp of the control region and 1,140 bp of cytochrome b sequences revealed the existence of two mtDNA clades. Control region haplotypes were much more divergent (d=3.39%) between the two clades than within each clade. The divergence of these clades may reflect differences at the subspecies or geographical population level in African penguins. These findings suggest that at least two distinct maternal lineages exist in the wild populations of the African penguin.
[PDF]
Nutcracker
Stop Brexit!
Or alternatively, the history of the captive specimens analysed has included misidentified / mislabelled individuals of other related species?? Hardly a rare occurrence!
Peter Kovalik
Well-known member
Eudyptula
Stefanie Grosser (student), Bruce C. Robertson and Jon M. Waters. Two fairy penguins go into a bar. Abstracts from the 2014 New Zealand Bird Conference, Palmerston North.
Abstract:
Little blue penguins, Eudyptula minor, are the smallest extant penguin species and inhabit the coasts of New Zealand and southern Australia. Since the species was described by Forster in 1781 the taxonomy of the genus Eudyptula has been subject to extensive revision. The white-flippered penguin found on Banks Peninsula, Canterbury, was described as a second species, Eudyptula albosignata. Based on morphological measurements of penguins from around New Zealand Kinsky and Falla reclassified E. minor into a single species containing 6 subspecies. The first molecular analysis suggested that no subspecies should berecognized, whereas more recent studies on mitochondrial DNA (mtDNA) discovered a split of E. minor into two highly divergent groups, suggesting the existence of two species of little blue penguin, one Australian (including birds from New Zealand’s Otago region) and one New Zealand species. Although the biology and genetics of little blue penguins have been intensively studied for many years, no consensus exists today about the taxonomy of these birds. In this study we are using mtDNA and 20 nuclear microsatellites to examine the population
structure of little blue penguins across their whole distributional range. Our analyses indicate the presence of two major genetic lineages within the New Zealand region, with little hybridization suggesting the possibility of two distinct biological taxa.
Stefanie Grosser (student), Bruce C. Robertson and Jon M. Waters. Two fairy penguins go into a bar. Abstracts from the 2014 New Zealand Bird Conference, Palmerston North.
Abstract:
Little blue penguins, Eudyptula minor, are the smallest extant penguin species and inhabit the coasts of New Zealand and southern Australia. Since the species was described by Forster in 1781 the taxonomy of the genus Eudyptula has been subject to extensive revision. The white-flippered penguin found on Banks Peninsula, Canterbury, was described as a second species, Eudyptula albosignata. Based on morphological measurements of penguins from around New Zealand Kinsky and Falla reclassified E. minor into a single species containing 6 subspecies. The first molecular analysis suggested that no subspecies should berecognized, whereas more recent studies on mitochondrial DNA (mtDNA) discovered a split of E. minor into two highly divergent groups, suggesting the existence of two species of little blue penguin, one Australian (including birds from New Zealand’s Otago region) and one New Zealand species. Although the biology and genetics of little blue penguins have been intensively studied for many years, no consensus exists today about the taxonomy of these birds. In this study we are using mtDNA and 20 nuclear microsatellites to examine the population
structure of little blue penguins across their whole distributional range. Our analyses indicate the presence of two major genetic lineages within the New Zealand region, with little hybridization suggesting the possibility of two distinct biological taxa.
Peter Kovalik
Well-known member
Peter Kovalik
Well-known member
Eri Kikkawa, Tomi T. Tsuda, Kazuyoshi Hosomiti, Michio Tsuda, Hidetoshi Inoko, Akinori Kimura, Taeko K. Naruse, Koich Murata. Molecular Evolutionary Analysis of Seven Species of Penguins (Order: Sphenisciformes) in MHC Class I Gene. Major Histocompatibility Complex, Vol. 22 (2015) No. 3 p. 156-163.
abstract and pdf here
abstract and pdf here
l_raty
laurent raty
Aptenodytes patagonicus
Clucas, Younger, Kao, Rogers, Handley, Miller, Jouventin, Nolan, Gharbi, Miller, Hart. 2016. Dispersal in the sub-Antarctic: king penguins show remarkably little population genetic differentiation across their range. BMC Evolutionary Biology 16:211.
[full paper]
Clucas, Younger, Kao, Rogers, Handley, Miller, Jouventin, Nolan, Gharbi, Miller, Hart. 2016. Dispersal in the sub-Antarctic: king penguins show remarkably little population genetic differentiation across their range. BMC Evolutionary Biology 16:211.
[full paper]
l_raty
laurent raty
Ramos, González-Acuña, Loyola, Johnson, Parker, Massaro, Dantas, Miranda, Vianna. 2018. Landscape genomics: natural selection drives the evolution of mitogenome in penguins. BMC Genomics 19:53.
[whole paper]
[whole paper]
Daniel Philippe
Well-known member
Chinstrap Penguin
Mura-Jornet I., Pimentel C., Dantas G.P.M., Petry M.V., González-Acuña D., Barbosa A., Lowther A.D., Kovacs K.M., Poulin E. & Vianna J.A., 2018. Chinstrap Penguin population genetic structure: one or more populations along the Southern Ocean? BMC Evol. Biol. 18 (90): 1-12.
Unavailable at present but should be here soon:
https://bmcevolbiol.biomedcentral.com/articles/10.1186/s12862-018-1207-0
Mura-Jornet I., Pimentel C., Dantas G.P.M., Petry M.V., González-Acuña D., Barbosa A., Lowther A.D., Kovacs K.M., Poulin E. & Vianna J.A., 2018. Chinstrap Penguin population genetic structure: one or more populations along the Southern Ocean? BMC Evol. Biol. 18 (90): 1-12.
Unavailable at present but should be here soon:
https://bmcevolbiol.biomedcentral.com/articles/10.1186/s12862-018-1207-0
There now!
Peter Kovalik
Well-known member
Cole, T.L., Rawlence, N.J., Dussex, N., Ellenberg, U., Houston, D.M., Mattern, T., Miskelly, C.M., Morrison, K.W., Paul Scofield, R., Tennyson, A.J.D., Thompson, D.R., Wood, J.R., Waters, J.M., Ancient DNA of crested penguins: Testing for temporal genetic shifts in the world’s most diverse penguin clade, Molecular Phylogenetics and Evolution (2018), doi: https://doi.org/10.1016/j.ympev.2018.10.025
Abstract:
Human impacts have substantially reduced avian biodiversity in many parts of the world, particularly on isolated islands of the Pacific Ocean. The New Zealand archipelago, including its five subantarctic island groups, holds breeding grounds for a third of the world’s penguin species, including several representatives of the diverse crested penguin genus Eudyptes. While this species-rich genus has been little studied genetically, recent population estimates indicate that several Eudyptes taxa are experiencing demographic declines. Although crested penguins are currently limited to southern regions of the New Zealand archipelago, prehistoric fossil and archaeological deposits suggest a wider distribution during prehistoric times, with breeding ranges perhaps extending to the North Island. Here, we analyse ancient, historic and modern DNA sequences to explore two hypotheses regarding the recent history of Eudyptes in New Zealand, testing for (1) human-driven extinction of Eudyptes lineages; and (2) reduced genetic diversity in surviving lineages. From 84 prehistoric bone samples, each tentatively identified as ‘Eudyptes spp.’, we genetically identified six prehistoric penguin taxa from mainland New Zealand, including one previously undescribed genetic lineage. Moreover, our Bayesian coalescent analyses indicated that, while the range of Fiordland crested penguin (E. pachyrhynchus) may have contracted markedly over the last millennium, genetic DNA diversity within this lineage has remained relatively constant. This result contrasts with human-driven biodiversity reductions previously detected in several New Zealand coastal vertebrate taxa.
Abstract:
Human impacts have substantially reduced avian biodiversity in many parts of the world, particularly on isolated islands of the Pacific Ocean. The New Zealand archipelago, including its five subantarctic island groups, holds breeding grounds for a third of the world’s penguin species, including several representatives of the diverse crested penguin genus Eudyptes. While this species-rich genus has been little studied genetically, recent population estimates indicate that several Eudyptes taxa are experiencing demographic declines. Although crested penguins are currently limited to southern regions of the New Zealand archipelago, prehistoric fossil and archaeological deposits suggest a wider distribution during prehistoric times, with breeding ranges perhaps extending to the North Island. Here, we analyse ancient, historic and modern DNA sequences to explore two hypotheses regarding the recent history of Eudyptes in New Zealand, testing for (1) human-driven extinction of Eudyptes lineages; and (2) reduced genetic diversity in surviving lineages. From 84 prehistoric bone samples, each tentatively identified as ‘Eudyptes spp.’, we genetically identified six prehistoric penguin taxa from mainland New Zealand, including one previously undescribed genetic lineage. Moreover, our Bayesian coalescent analyses indicated that, while the range of Fiordland crested penguin (E. pachyrhynchus) may have contracted markedly over the last millennium, genetic DNA diversity within this lineage has remained relatively constant. This result contrasts with human-driven biodiversity reductions previously detected in several New Zealand coastal vertebrate taxa.
Daniel Philippe
Well-known member
Cole T.L., Ksepka D.T., Mitchell K.J., Tennyson A.J.D., Thomas D.B., Pan H., Zhang G., Rawlence N.J., Wood J.R., Bover P., Bouzat J.L., Cooper A., Fiddaman S., Hart T., Miller G., Ryan P.G., Shepherd L.D., Wilmshurst J.M. & Waters J.M., in press. Mitogenomes uncover extinct penguin taxa and reveal island formation as a key driver of speciation. Mol. Biol. Evol.
There
There
Fred Ruhe
Well-known member
I already mentioned this paper on februari 7th 2019. See: https://www.birdforum.net/showthread.php?t=372871
Fred
Peter Kovalik
Well-known member
Eudyptes chrysolophus, Eudyptes schlegeli
María José Frugone, María Eugenia López, Nicolás I. Segovia, Theresa L. Cole, Andrew Lother, Pierre Pistorius, Gisele P.M. Dantas, Maria Virginia Petri, Francesco Bonadonna, Phil Trathan, Andrea Polanowski, Barbara Wienecke, Ke Bi, Cynthia Y. Wang-Claypool, Jonathan M. Waters, Rauri C.K. Bowie, Elie Poulin, Juliana A. Vianna. More than the eye can see: genomic insights into the drivers of genetic differentiation in Royal/Macaroni penguins across the Southern Ocean. Molecular Phylogenetics and Evolution. In Press, Accepted Manuscript, Available online 16 July 2019. https://doi.org/10.1016/j.ympev.2019.106563
Abstract:
The study of systematics in wide-ranging seabirds can be challenging due to the vast geographic scales involved, as well as the possible discordance between molecular, morphological and behavioral data. In the Southern Ocean, macaroni penguins (Eudyptes chrysolophus) are distributed over a circumpolar range including populations in Antarctic and sub-Antarctic areas. Macquarie Island, in its relative isolation, is home to a closely related endemic taxon — the royal penguin (Eudyptes schlegeli), which is distinguishable from E. chrysolophus mainly by facial coloration. Although these sister taxa are widely accepted as representing distinct species based on morphological grounds, the extent of their genome-wide differentiation remains uncertain. In this study, we use genome-wide Single Nucleotide Polymorphisms to test genetic differentiation between these geographically isolated taxa and evaluate the main drivers of population structure among breeding colonies of macaroni/royal penguins. Genetic similarity observed between macaroni and royal penguins suggests they constitute a single evolutionary unit. Nevertheless, royal penguins exhibited a tendency to cluster only with macaroni individuals from Kerguelen Island, suggesting that dispersal occurs mainly between neighborhood colonies. A stepping stone model of differentiation of macaroni/royal populations was further supported by a strong pattern of isolation by distance detected across its whole distribution range, possibly driven by large geographic distances between colonies as well as natal philopatry. However, we also detected intraspecific genomic differentiation between Antarctic and sub-Antarctic populations of macaroni penguins, highlighting the role of environmental factors together with geographic distance in the processes of genetic differentiation between Antarctic and sub-Antarctic waters.
María José Frugone, María Eugenia López, Nicolás I. Segovia, Theresa L. Cole, Andrew Lother, Pierre Pistorius, Gisele P.M. Dantas, Maria Virginia Petri, Francesco Bonadonna, Phil Trathan, Andrea Polanowski, Barbara Wienecke, Ke Bi, Cynthia Y. Wang-Claypool, Jonathan M. Waters, Rauri C.K. Bowie, Elie Poulin, Juliana A. Vianna. More than the eye can see: genomic insights into the drivers of genetic differentiation in Royal/Macaroni penguins across the Southern Ocean. Molecular Phylogenetics and Evolution. In Press, Accepted Manuscript, Available online 16 July 2019. https://doi.org/10.1016/j.ympev.2019.106563
Abstract:
The study of systematics in wide-ranging seabirds can be challenging due to the vast geographic scales involved, as well as the possible discordance between molecular, morphological and behavioral data. In the Southern Ocean, macaroni penguins (Eudyptes chrysolophus) are distributed over a circumpolar range including populations in Antarctic and sub-Antarctic areas. Macquarie Island, in its relative isolation, is home to a closely related endemic taxon — the royal penguin (Eudyptes schlegeli), which is distinguishable from E. chrysolophus mainly by facial coloration. Although these sister taxa are widely accepted as representing distinct species based on morphological grounds, the extent of their genome-wide differentiation remains uncertain. In this study, we use genome-wide Single Nucleotide Polymorphisms to test genetic differentiation between these geographically isolated taxa and evaluate the main drivers of population structure among breeding colonies of macaroni/royal penguins. Genetic similarity observed between macaroni and royal penguins suggests they constitute a single evolutionary unit. Nevertheless, royal penguins exhibited a tendency to cluster only with macaroni individuals from Kerguelen Island, suggesting that dispersal occurs mainly between neighborhood colonies. A stepping stone model of differentiation of macaroni/royal populations was further supported by a strong pattern of isolation by distance detected across its whole distribution range, possibly driven by large geographic distances between colonies as well as natal philopatry. However, we also detected intraspecific genomic differentiation between Antarctic and sub-Antarctic populations of macaroni penguins, highlighting the role of environmental factors together with geographic distance in the processes of genetic differentiation between Antarctic and sub-Antarctic waters.
Fred Ruhe
Well-known member
Hailin Pan, Theresa L Cole, Xupeng Bi, Miaoquan Fang, Chengran Zhou, Zhengtao Yang, Daniel T Ksepka, Tom Hart, Juan L Bouzat, Lisa S Argilla, Mads F Bertelsen, P Dee Boersma, Charles-Andrà Bost, Yves Cherel, Peter Dann, Steven R Fiddaman, Pauline Howard, Kim Labuschagne, Thomas Mattern, Gary Miller, Patricia Parker, Richard A Phillips, Petra Quillfeldt, Peter G Ryan, Helen Taylor, David R Thompson, Melanie J Young, Martin R Ellegaard, M Thomas P Gilbert, Mikkel-Holger S Sinding, George Pacheco, Lara D Shepherd, Alan J D Tennyson, Stefanie Grosser, Emily Kay, Lisa J Nupen, Ursula Ellenberg, David M Houston, Andrew Hart Reeve, Kathryn Johnson, Juan F Masello, Thomas Stracke, Bruce McKinlay, Pablo GarcÃa Borboroglu, De-Xing Zhang & Guojie Zhang, 2019
High-coverage genomes to elucidate the evolution of penguins.
GigaScience 8(9): giz117
doi: https://doi.org/10.1093/gigascience/giz117
Abstract: https://academic.oup.com/gigascience/article/8/9/giz117/5571031
Background
Penguins (Sphenisciformes) are a remarkable order of flightless wing-propelled diving seabirds distributed widely across the southern hemisphere. They share a volant common ancestor with Procellariiformes close to the Cretaceous-Paleogene boundary (66 million years ago) and subsequently lost the ability to fly but enhanced their diving capabilities. With ∼20 species among 6 genera, penguins range from the tropical Galápagos Islands to the oceanic temperate forests of New Zealand, the rocky coastlines of the sub-Antarctic islands, and the sea ice around Antarctica. To inhabit such diverse and extreme environments, penguins evolved many physiological and morphological adaptations. However, they are also highly sensitive to climate change. Therefore, penguins provide an exciting target system for understanding the evolutionary processes of speciation, adaptation, and demography. Genomic data are an emerging resource for addressing questions about such processes.
Results
Here we present a novel dataset of 19 high-coverage genomes that, together with 2 previously published genomes, encompass all extant penguin species. We also present a well-supported phylogeny to clarify the relationships among penguins. In contrast to recent studies, our results demonstrate that the genus Aptenodytes is basal and sister to all other extant penguin genera, providing intriguing new insights into the adaptation of penguins to Antarctica. As such, our dataset provides a novel resource for understanding the evolutionary history of penguins as a clade, as well as the fine-scale relationships of individual penguin lineages. Against this background, we introduce a major consortium of international scientists dedicated to studying these genomes. Moreover, we highlight emerging issues regarding ensuring legal and respectful indigenous consultation, particularly for genomic data originating from New Zealand Taonga species.
Conclusions
We believe that our dataset and project will be important for understanding evolution, increasing cultural heritage and guiding the conservation of this iconic southern hemisphere species assemblage.
Free pdf https://watermark.silverchair.com/g...derg_WpxIZXBRjDyTWGxRlTfcLhIeuVOG4V8J6C607N9E
Enjoy,
Fred
High-coverage genomes to elucidate the evolution of penguins.
GigaScience 8(9): giz117
doi: https://doi.org/10.1093/gigascience/giz117
Abstract: https://academic.oup.com/gigascience/article/8/9/giz117/5571031
Background
Penguins (Sphenisciformes) are a remarkable order of flightless wing-propelled diving seabirds distributed widely across the southern hemisphere. They share a volant common ancestor with Procellariiformes close to the Cretaceous-Paleogene boundary (66 million years ago) and subsequently lost the ability to fly but enhanced their diving capabilities. With ∼20 species among 6 genera, penguins range from the tropical Galápagos Islands to the oceanic temperate forests of New Zealand, the rocky coastlines of the sub-Antarctic islands, and the sea ice around Antarctica. To inhabit such diverse and extreme environments, penguins evolved many physiological and morphological adaptations. However, they are also highly sensitive to climate change. Therefore, penguins provide an exciting target system for understanding the evolutionary processes of speciation, adaptation, and demography. Genomic data are an emerging resource for addressing questions about such processes.
Results
Here we present a novel dataset of 19 high-coverage genomes that, together with 2 previously published genomes, encompass all extant penguin species. We also present a well-supported phylogeny to clarify the relationships among penguins. In contrast to recent studies, our results demonstrate that the genus Aptenodytes is basal and sister to all other extant penguin genera, providing intriguing new insights into the adaptation of penguins to Antarctica. As such, our dataset provides a novel resource for understanding the evolutionary history of penguins as a clade, as well as the fine-scale relationships of individual penguin lineages. Against this background, we introduce a major consortium of international scientists dedicated to studying these genomes. Moreover, we highlight emerging issues regarding ensuring legal and respectful indigenous consultation, particularly for genomic data originating from New Zealand Taonga species.
Conclusions
We believe that our dataset and project will be important for understanding evolution, increasing cultural heritage and guiding the conservation of this iconic southern hemisphere species assemblage.
Free pdf https://watermark.silverchair.com/g...derg_WpxIZXBRjDyTWGxRlTfcLhIeuVOG4V8J6C607N9E
Enjoy,
Fred
Last edited:
Jacana
Will Jones
Vianna JA, et al. 2020. Genome-wide analyses reveal drivers of penguin diversification. PNAS. https://doi.org/10.1073/pnas.2006659117
Significance
Penguins have long been of interest to scientists and the general public, but their evolutionary history remains unresolved. Using genomes, we investigated the drivers of penguin diversification. We found that crown-group penguins diverged in the early Miocene in Australia/New Zealand and identified Aptenodytes (emperor and king penguins) as the sister group to all other extant penguins. Penguins first occupied temperate environments and then radiated to cold Antarctic waters. The Antarctic Circumpolar Current’s (ACC) intensification 11.6 Mya promoted penguin diversification and geographic expansion. We detected interspecies introgression among penguins, in some cases following the direction of the ACC, and identified genes acting on thermoregulation, oxygen metabolism, and diving capacity that underwent adaptive evolution as they progressively occupied more challenging thermal niches.
Abstract
Penguins are the only extant family of flightless diving birds. They currently comprise at least 18 species, distributed from polar to tropical environments in the Southern Hemisphere. The history of their diversification and adaptation to these diverse environments remains controversial. We used 22 new genomes from 18 penguin species to reconstruct the order, timing, and location of their diversification, to track changes in their thermal niches through time, and to test for associated adaptation across the genome. Our results indicate that the penguin crown-group originated during the Miocene in New Zealand and Australia, not in Antarctica as previously thought, and that Aptenodytes is the sister group to all other extant penguin species. We show that lineage diversification in penguins was largely driven by changing climatic conditions and by the opening of the Drake Passage and associated intensification of the Antarctic Circumpolar Current (ACC). Penguin species have introgressed throughout much of their evolutionary history, following the direction of the ACC, which might have promoted dispersal and admixture. Changes in thermal niches were accompanied by adaptations in genes that govern thermoregulation and oxygen metabolism. Estimates of ancestral effective population sizes (Ne) confirm that penguins are sensitive to climate shifts, as represented by three different demographic trajectories in deeper time, the most common (in 11 of 18 penguin species) being an increased Ne between 40 and 70 kya, followed by a precipitous decline during the Last Glacial Maximum. The latter effect is most likely a consequence of the overall decline in marine productivity following the last glaciation.
Significance
Penguins have long been of interest to scientists and the general public, but their evolutionary history remains unresolved. Using genomes, we investigated the drivers of penguin diversification. We found that crown-group penguins diverged in the early Miocene in Australia/New Zealand and identified Aptenodytes (emperor and king penguins) as the sister group to all other extant penguins. Penguins first occupied temperate environments and then radiated to cold Antarctic waters. The Antarctic Circumpolar Current’s (ACC) intensification 11.6 Mya promoted penguin diversification and geographic expansion. We detected interspecies introgression among penguins, in some cases following the direction of the ACC, and identified genes acting on thermoregulation, oxygen metabolism, and diving capacity that underwent adaptive evolution as they progressively occupied more challenging thermal niches.
Abstract
Penguins are the only extant family of flightless diving birds. They currently comprise at least 18 species, distributed from polar to tropical environments in the Southern Hemisphere. The history of their diversification and adaptation to these diverse environments remains controversial. We used 22 new genomes from 18 penguin species to reconstruct the order, timing, and location of their diversification, to track changes in their thermal niches through time, and to test for associated adaptation across the genome. Our results indicate that the penguin crown-group originated during the Miocene in New Zealand and Australia, not in Antarctica as previously thought, and that Aptenodytes is the sister group to all other extant penguin species. We show that lineage diversification in penguins was largely driven by changing climatic conditions and by the opening of the Drake Passage and associated intensification of the Antarctic Circumpolar Current (ACC). Penguin species have introgressed throughout much of their evolutionary history, following the direction of the ACC, which might have promoted dispersal and admixture. Changes in thermal niches were accompanied by adaptations in genes that govern thermoregulation and oxygen metabolism. Estimates of ancestral effective population sizes (Ne) confirm that penguins are sensitive to climate shifts, as represented by three different demographic trajectories in deeper time, the most common (in 11 of 18 penguin species) being an increased Ne between 40 and 70 kya, followed by a precipitous decline during the Last Glacial Maximum. The latter effect is most likely a consequence of the overall decline in marine productivity following the last glaciation.
Peter Kovalik
Well-known member
IOC Updates Diary Oct 19
Revise sequence of genera and species within Spheniscidae to reflect Vianna et al. (2020).
Peter Kovalik
Well-known member
María José Frugone, Theresa L. Cole, María Eugenia López, Gemma Clucas, Pável Matos-Maraví, Nicolás A. Lois, Pierre Pistorius, Francesco Bonadonna, Phil Trathan, Andrea Polanowski, Barbara Wienecke, Andrea Raya-Rey, Klemens Pütz, Antje Steinfurth, Ke Bi, Cynthia Y. Wang-Claypool, Jonathan M. Waters, Rauri C. K. Bowie, Elie Poulin, and Juliana A. Vianna. 2021. Taxonomy based on limited genomic markers may underestimate species diversity of rockhopper penguins and threaten their conservation.
Diversity and Distributions. First published: 23 September 2021.
https://doi.org/10.1111/ddi.13399
Abstract
Aim
Delimiting recently diverged species is challenging. During speciation, genetic differentiation may be distributed unevenly across the genome, as different genomic regions can be subject to different selective pressures and evolutionary histories. Reliance on limited numbers of genetic markers that may be underpowered can make species delimitation even more challenging, potentially resulting in taxonomic inconsistencies. Rockhopper penguins of the genus Eudyptes comprise three broadly recognized taxa: northern (E. moseleyi), southern (E. chrysocome) and eastern rockhopper (E. filholi). Their taxonomic status has been controversial for decades, with researchers disagreeing about whether E. chrysocome and E. filholi are distinct species or conspecific. Our goal is to evaluate genome-wide patterns of divergence to evaluate genetic differentiation and species delimitation in rockhopper penguins, and to assess which mechanisms may underlie previous discordance among nuclear versus mitochondrial analyses.
Location
Sub-Antarctic and temperate coastal regions of the Southern Hemisphere.
Methods
We generated reduced-representation genomic libraries using double digest restriction-site associated DNA (ddRAD) sequencing to evaluate genetic differentiation, contemporary migration rates and admixture among colonies of rockhopper penguins.
Results
The extent of genetic differentiation among the three taxa was consistently higher than population-level genetic differentiation found within these and other penguin species. There was no evidence of admixture among the three taxa, suggesting the absence of ongoing gene flow among them. Species delimitation analyses based on molecular data, along with other lines of evidence, provide strong support for the taxonomic distinction of three species of rockhopper penguins.
Main conclusions
Our results provide strong support for the existence of three distinct species of rockhopper penguins. The recognition of this taxonomic diversity is crucial for the management and conservation of this widely distributed species group. This study illustrates that widespread dispersive seabird lineages lacking obvious morphological differences may nevertheless have complex evolutionary histories and comprise cryptic species diversity.
Diversity and Distributions. First published: 23 September 2021.
https://doi.org/10.1111/ddi.13399
Abstract
Aim
Delimiting recently diverged species is challenging. During speciation, genetic differentiation may be distributed unevenly across the genome, as different genomic regions can be subject to different selective pressures and evolutionary histories. Reliance on limited numbers of genetic markers that may be underpowered can make species delimitation even more challenging, potentially resulting in taxonomic inconsistencies. Rockhopper penguins of the genus Eudyptes comprise three broadly recognized taxa: northern (E. moseleyi), southern (E. chrysocome) and eastern rockhopper (E. filholi). Their taxonomic status has been controversial for decades, with researchers disagreeing about whether E. chrysocome and E. filholi are distinct species or conspecific. Our goal is to evaluate genome-wide patterns of divergence to evaluate genetic differentiation and species delimitation in rockhopper penguins, and to assess which mechanisms may underlie previous discordance among nuclear versus mitochondrial analyses.
Location
Sub-Antarctic and temperate coastal regions of the Southern Hemisphere.
Methods
We generated reduced-representation genomic libraries using double digest restriction-site associated DNA (ddRAD) sequencing to evaluate genetic differentiation, contemporary migration rates and admixture among colonies of rockhopper penguins.
Results
The extent of genetic differentiation among the three taxa was consistently higher than population-level genetic differentiation found within these and other penguin species. There was no evidence of admixture among the three taxa, suggesting the absence of ongoing gene flow among them. Species delimitation analyses based on molecular data, along with other lines of evidence, provide strong support for the taxonomic distinction of three species of rockhopper penguins.
Main conclusions
Our results provide strong support for the existence of three distinct species of rockhopper penguins. The recognition of this taxonomic diversity is crucial for the management and conservation of this widely distributed species group. This study illustrates that widespread dispersive seabird lineages lacking obvious morphological differences may nevertheless have complex evolutionary histories and comprise cryptic species diversity.
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