[PaleoOrnithology • 2017] Ancient DNA and Morphometric Analysis Reveal Extinction and Replacement of New Zealand's Unique Black Swans, Cygnus sumnerensis ---ScRaBBlE

The skeleton of the poūwa, Cygnus sumnerensis (Forbes, 1890) 

Rawlence, Kardamaki, Easton, et al. 2017.

 Ancient DNA and Morphometric Analysis Reveal Extinction and Replacement of New Zealand's Unique Black Swans.  Proceedings of the Royal Society B.  DOI:  10.1098/rspb.2017.0876 

Abstract

Prehistoric human impacts on megafaunal populations have dramatically reshaped ecosystems worldwide. However, the effects of human exploitation on smaller species, such as anatids (ducks, geese, and swans) are less clear. In this study we apply ancient DNA and osteological approaches to reassess the history of Australasia's iconic black swans (Cygnus atratus) including the palaeo-behaviour of prehistoric populations. Our study shows that at the time of human colonization, New Zealand housed a genetically, morphologically, and potentially ecologically distinct swan lineage (Cygnus sumnerensis, Poūwa), divergent from modern (Australian) C. atratus. Morphological analyses indicate C. sumnerensis exhibited classic signs of the ‘island rule’ effect, being larger, and likely flight-reduced compared to C. atratus. Our research reveals sudden extinction and replacement events within this anatid species complex, coinciding with recent human colonization of New Zealand. This research highlights the role of anthropogenic processes in rapidly reshaping island ecosystems and raises new questions for avian conservation, ecosystem re-wilding, and de-extinction.

KEYWORDS:  ancient-DNA, Australia, black swan, Chatham Islands, Cygnus atratus, Cygnus sumnerensis, Q1 extinction, island rule, New Zealand, Poūwa, recolonization

The skeleton of the extinct poūwa.

Jean-Claude Stahl / Museum of New Zealand Te Papa Tongarewa 

The mounted bones of an extinct poūwa.

Photo: Museum of New Zealand Te Papa Tongarewa

Nicolas J. Rawlence, Afroditi Kardamaki, Luke J. Easton, Alan J. D. Tennyson, R. Paul Scofield and Jonathan M. Waters. 2017. Ancient DNA and Morphometric Analysis Reveal Extinction and Replacement of New Zealand's Unique Black Swans.
 Proceedings of the Royal Society B.  DOI:  10.1098/rspb.2017.0876

https://assets.documentcloud.org/documents/3900672/Ancient-DNA-and-morphometric-analysis-reveal.pdf

 Introducing the Poūwa: New Zealand’s unique and ill-fated black swan
sciblogs.co.nz/guestwork/2017/07/26/introducing-pouwa-new-zealands-unique-ill-fated-black-swan/  @sciblogsnz

The legend of Poūwa: ancient myths of New Zealand's black swan confirmed by fossil DNA
 theconversation.com/the-legend-of-pouwa-ancient-myths-of-new-zealands-black-swan-confirmed-by-fossil-dna-81611 @ConversationEDU

NZ's ill-fated burly black swan  radionz.co.nz/news/national/335850/nz-s-ill-fated-burly-black-swan

  

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل

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شاهد هذا الفيديو القصير لطريقة التحميل البسيطة

منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات

كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا

شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا

رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا

تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[Entomology • 2017] Evolutionary Assembly of Communities in Butterfly Mimicry Rings ---ScRaBBlE

in Joshi, Prakash & Kunte, 2017. 
DOI:  10.1086/690907  twitter.com/ASNAmNat

Abstract

 Species co-occurrence in ecological communities is thought to be influenced by multiple ecological and evolutionary processes, especially colonization and competition. However, effects of other interspecific interactions and evolutionary relationships are less explored. We examined evolutionary histories of community members and roles of mutualistic and parasitic interactions (Müllerian and Batesian mimicry, respectively) in the assembly of mimetic butterfly communities called mimicry rings in tropical forests of the Western Ghats, India. We found that Müllerian mimics were phylogenetically clustered, sharing aposematic signals due to common ancestry. On the other hand, Batesian mimics joined mimicry rings through convergent evolution and random phylogenetic assembly. Since the Western Ghats are a habitat island, we compared species diversity and composition in its mimicry rings with those of habitat mainland to test effects of biogeographic connectivity. The Western Ghats consisted of fewer mimicry rings and an overall smaller number of aposematic species and mimics compared to habitat mainland. The depauperate mimicry rings in the Western Ghats could have resulted from stochastic processes, reflecting their long temporal and spatial isolation and trickling colonization by the mimetic butterfly communities. These results highlight how evolutionary history, biogeographic isolation, and stochastic colonization influence the evolutionary assembly and diversity of ecological communities.

Keywords: phylogenetic community ecology, community dynamics, island biogeography, Batesian mimicry, Müllerian mimicry.

      

Figure 1. Mimicry rings in the Western Ghats, India, showing spatial and temporal overlap between Batesian mimics and aposematic species and their mimicry phenotypes. Each mimicry ring is named after the predominant species or genus of aposematic species. In the phenological tables, J–D represent months in a year; monthly occurrence of aposematic species and Batesian mimics are shown in green, and absence is shown in white; and in each mimicry ring, aposematic species are listed before Batesian mimics, separated by a black line. Most aposematic species and Batesian mimics overlap in time. The distributional maps on the outline of the Western Ghats show spatial overlap between aposematic species and Batesian mimics. Green areas represent distributions of aposematic species, where darker green areas show more restricted distributions of one or more aposematic species when multiple aposematic species exist in mimicry rings. Black spots on these maps show distributions of Batesian mimetic species, with yellow spots representing narrower distributions of some of the Batesian mimetic specie. Distributional ranges of Batesian mimics are embedded within the distributional ranges of aposematic species, signifying ecological dependence of Batesian mimics on the presence of aposematic species.

Jahnavi Joshi, Anupama Prakash and Krushnamegh Kunte. 2017. Evolutionary Assembly of Communities in Butterfly Mimicry Rings. The American Naturalist. 189(4); E58-E76.  DOI:  10.1086/690907

 twitter.com/ASNAmNat/status/978738248930549760

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل

من هنا

او

من هنا

شاهد هذا الفيديو القصير لطريقة التحميل البسيطة

منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات

كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا

شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا

رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا

تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.