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[Ornithology • 2017] Myzomela irianawidodoae • A Colourful New Species of Myzomela Honeyeater from Rote Island in eastern Indonesia ---ScRaBBlE

Myzomela irianawidodoae Prawiradilaga, Baveja, Suparno, Ashari, Ng, Gwee, Verbelen & Rheindt, 2017  photo:   Philippe Verbelen  e-journ...

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Showing posts with label Diversification. Show all posts
Showing posts with label Diversification. Show all posts

Wednesday, March 20, 2019

[Herpetology • 2017] Arboreality Constrains Morphological Evolution but Not Species Diversification in Vipers ---ScRaBBlE


Stejneger's Pitviper (Trimeresurus stejnegeri

 Alencar, Martins, Burin & Quental, 2017
    DOI: 10.1098/rspb.2017.1775 

Abstract
An increase in ecological opportunities, either through changes in the environment or acquisition of new traits, is frequently associated with an increase in species and morphological diversification. However, it is possible that certain ecological settings might prevent lineages from diversifying. Arboreality evolved multiple times in vipers, making them ideal organisms for exploring how potentially new ecological opportunities affect their morphology and speciation regimes. Arboreal snakes are frequently suggested to have a very specialized morphology, and being too large, too small, too heavy, or having short tails might be challenging for them. Using trait-evolution models, we show that arboreal vipers are evolving towards intermediate body sizes, with longer tails and more slender bodies than terrestrial vipers. Arboreality strongly constrains body size and circumference evolution in vipers, while terrestrial lineages are evolving towards a broader range of morphological variants. Trait-dependent diversification models, however, suggest similar speciation rates between microhabitats. Thus, we show that arboreality might constrain morphological evolution but not necessarily affect the rates at which lineages generate new species.

KEYWORDS: speciation, divergent selection, snakes, Ornstein–Uhlenbeck

The arboreal Stejneger's Pitviper (Trimeresurus stejnegeri).

Photo: M. Martins 

Laura Rodrigues Vieira de Alencar, Marcio Martins, Gustavo Burin and Tiago Bosisio Quental. 2017. Arboreality Constrains Morphological Evolution but Not Species Diversification in Vipers. Proceedings of the Royal Society B: Biological Sciences. 284(1869)  DOI: 10.1098/rspb.2017.1775 

    

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


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.

[Herpetology • 2017] Diversification in Arid Mountains: Biogeography and Cryptic Diversity of Pristurus rupestris rupestris in Arabia ---ScRaBBlE


 Pristurus r. rupetris of the high altitude robust morphotype.
  Panoramic view of Wadi Sareen, a Protected Area that includes the only known locality of one of the new species discovered in this study.



Abstract

Aim
To understand the patterns of genetic, geographical and morphological diversification in the Arabian gecko subspecies Pristurus rupestris rupestris, and to discuss the various processes that generate and shape diversity in arid mountain ranges.

Location
Hajar Mountains, south-eastern Arabian Peninsula.

Methods
We sampled 466 individuals across the entire range of P. r. rupestris in the Hajar Mountains and sequenced one mitochondrial gene for all the samples, and one extra mitochondrial and four nuclear genes for a subset of 75 specimens. A total of 155 individuals were characterized morphologically. Multilocus coalescent-based methods were used for species delimitation, for phylogenetic inference of species trees and to investigate the diversification dynamics. Multivariate statistics were used to analyse morphological data.

Results
Our molecular methods revealed 14 candidate species hidden within the subspecies P. r. rupestris. Diversification started c. 15 Ma, but most of the lineages have evolved in the last 7 Ma of the mountains’ orogeny, producing a mosaic of allopatric taxa. Secondary interchange has occurred between high and low elevation lineages, and along the mountain chain between unrelated lineages formerly separated by mountain blocks. Morphological variation between the 14 candidate species is slight, but a high elevation robust morphotype is identified.

Main conclusions
Our results support the notion that mountain ranges constitute important centres of diversification in arid regions, and also act as ‘species pumps’ into surrounding areas. We also demonstrate that arid mountains may constitute important reservoirs of cryptic diversity, even in common and widespread species. This, and previous evidence, suggest that the Hajar Mountains are a biological hotspot and an important reservoir of diversity. We therefore suggest that these mountains should be a priority focal point for conservation in Arabia.

Keywords: allopatry; Arabia; arid mountains; biodiversity; biogeography; cryptic species; diversification; evolution; systematics

Photo 1: Pristurus r. rupetris of the high altitude robust morphotype.
photo: S. Carranza.  

Photo 2: Panoramic view of Wadi Sareen, a Protected Area that includes the only known locality of one of the new species discovered in this study.
photo: S. Carranza. 

Joan Garcia-Porta, Marc Simó-Riudalbas, Michael Robinson and Salvador Carranza. 2017. Diversification in Arid Mountains: Biogeography and Cryptic Diversity of Pristurus rupestris rupestris in Arabia.  Journal of Biogeography. DOI: 10.1111/jbi.12929 

Scientists uncover 14 new gecko species within a single subspecies - Oman
 http://www.muscatdaily.com/Archive/Oman/Scientists-uncover-14-new-gecko-species-within-a-single-subspecies-4ykk


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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


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.

[Herpetology • 2017] A Phylogeny of Open-habitat Lizards (Squamata: Lacertidae: Ophisops) Supports the Antiquity of Indian Grassy Biomes ---ScRaBBlE




Abstract

Aim: India is dominated by tropical grassy biomes (TGBs), traditionally considered seres or degraded forest, with low diversity relative to the restricted, ancestral wet zone. It is unclear if Indian grasslands and other open habitats are anthropogenically derived or native, old-growth habitats; without a clear timescale of grassland evolution. One way to understand grassland evolution is to study the diversification in taxa restricted to open habitats. We use a dated phylogeny of Ophisops to address questions related to the origin, diversification and inter-relationships of Indian and Saharo-Arabian Ophisops, and ultimately the origin of Indian grasslands and open habitats.

Location: The Indian subcontinent; the Saharo-Arabian Realm.

Methods: We generated up to 2736 base pairs of aligned sequence data (one mitochondrial, two nuclear genes) for Indian lacertids and reconstructed phylogenetic relationships using maximum likelihood and Bayesian inference. We use a fossil-calibrated timetree, diversification analyses and ancestral area reconstructions to test the hypotheses of origin and relationships with Saharo-Arabian Ophisops.

Results: Ophisops is strongly supported as monophyletic, with a basal split into a large-bodied (LBC) and small-bodied clade (SBC). The Saharo-Arabian species are nested within the Indian species in the LBC. Species diversity in Indian Ophisops is grossly underestimated, with 26–47 candidate species. Ophisops began diversifying in the late Oligocene with significant rate shifts in the late Miocene-Pliocene and Pleistocene within the SBC.

Main conclusions: Our results are consistent with an ancient origin of grassland taxa and TGBs in India. Ophisops is a dramatic example of overlooked cryptic diversity outside forests, with ~30 species where five were known. Ophisops dispersed into India from the Saharo-Arabian Realm in the Oligocene with a back dispersal in the Middle Miocene, a novel biogeographical pattern. Diversification in the SBC of Ophisops increased 8-fold during the global C4 grassland expansion. Indian TGBs are old-growth ecosystems that need urgent conservation attention.




Habitats of Ophisops leschenaultii species complex, Tumkur District, Karnataka. 
  

Ishan Agarwal and Uma Ramakrishnan. 2017. A Phylogeny of Open-habitat Lizards (Squamata: Lacertidae: Ophisops) Supports the Antiquity of Indian Grassy Biomes.  Journal of Biogeography. DOI: 10.1111/jbi.12999

How lizards revealed the millennia-old evolution story of India’s grasslands
  
  

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


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.

[Ichthyology • 2017] Sex-specific Evolution during the Diversification of Live-bearing Fishes ---ScRaBBlE


Samples of fish species from the Poeciliidae family show the diversity in color, fin size and body shape. Kansas State University researchers studied 112 species of these live-bearing fishes and found that males and females evolve differently.


Abstract
Natural selection is often assumed to drive parallel functional diversification of the sexes. But males and females exhibit fundamental differences in their biology, and it remains largely unknown how sex differences affect macroevolutionary patterns. On microevolutionary scales, we understand how natural and sexual selection interact to give rise to sex-specific evolution during phenotypic diversification and speciation. Here we show that ignoring sex-specific patterns of functional trait evolution misrepresents the macroevolutionary adaptive landscape and evolutionary rates for 112 species of live-bearing fishes (Poeciliidae). Males and females of the same species evolve in different adaptive landscapes. Major axes of female morphology were correlated with environmental variables but not reproductive investment, while male morphological variation was primarily associated with sexual selection. Despite the importance of both natural and sexual selection in shaping sex-specific phenotypic diversification, species diversification was overwhelmingly associated with ecological divergence. Hence, the inter-predictability of mechanisms of phenotypic and species diversification may be limited in many systems. These results underscore the importance of explicitly addressing sex-specific diversification in empirical and theoretical frameworks of evolutionary radiations to elucidate the roles of different sources of selection and constraint.


Samples of fish species from the Poeciliidae family show the diversity in color, fin size and body shape. Kansas State University researchers studied 112 species of these live-bearing fishes and found that males and females evolve differently.

  

 Conclusions 
Some of our most basic tenets and enduring theories of evolution have come from systems in which phenotypes or species have diversified in response to putatively clear and strong sources of selection. However, even in those systems, evolutionary dynamics are more complex than previously assumed. Compartmentalizing our understanding of diversification into male or female (or, worse yet, sex averages), natural or sexual selection, phenotypic or species patterns, and micro- or macroevolution provides an incomplete assessment of evolutionary patterns and processes. Only integrative analysis of evolutionary dynamics across these areas will allow us to develop robust understanding of the origins of biodiversity.


Zachary W. Culumber and Michael Tobler. 2017. Sex-specific Evolution during the Diversification of Live-bearing Fishes.
 Nature Ecology & Evolution. DOI: 10.1038/s41559-017-0233-4

A tale of two fishes: Biologists find male, female live-bearing fish evolve differently
 phy.so/419594245 via @physorg_com


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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


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] Phylogeny and Diversification of the Cloud Forest Morpho sulkowskyi Group (Lepidoptera, Nymphalidae) in the Evolving Andes ---ScRaBBlE



Abstract

The monophyletic Morpho sulkowskyi butterfly group, endemic of Andean cloud forests, was studied to test the respective contributions of Mio-Pliocene intense uplift period and Pleistocene glacial cycles on Andean biodiversity. We sampled nine taxa covering the whole geographical range of the group. Two mitochondrial and two nuclear genes were analysed using a Bayesian method. We established a dated phylogeny of the group using a relaxed clock method and a wide-outgroup approach. To discriminate between two hypotheses, we used a biogeographical probabilistic method. Results suggest that the ancestor of the M. sulkowskyi group originated during the Middle–Late Miocene uplift of the Eastern Cordillera in northern Peru. Biogeographical inference suggests that the M. sulkowskyi and Morpho lympharis clades diverged in the northern Peruvian Andes. The subsequent divergences, from the Late Miocene to the Late Pliocene, should have resulted from a dispersal towards the Northern Andes (M. sulkowskyi clade), after the closure of the West Andean Portal separating the Central and Northern Andes, and a southwards dispersal along the Peruvian and Bolivian Eastern Cordilleras (M. lympharis clade). Only a few divergences occurred at the very end of the Pliocene or during the Pleistocene, a period when the more recent uplifts interfered with Pleistocene glacial cycles.

Figure 1.  Map of the region where field studies were carried out, with habitus of the taxa calderoni, zachi and nieva (m: male; f: female; f1 and f2: female morphs within the calderoni population). N1 and N2: sampling areas along the upper Río Nieva. Other localities where specimens were collected: AP: Abra Patricia; EF: El Afluente; OP: Oso Perdido; PM: Abra Pardo Miguel; V: Venceremos. Two specimens of nieva were also collected at Santa Cruz del Mirador (M), at ca. 20 km ESE from El Afluente. 

Conclusions
Simple relationships between Andean uplift and the diversification of various plant and animal groups, implying pre-Pleistocene driving processes, have been supposed by various authors. Doan (2003), for example, proposed the south-to-north speciation hypothesis, where the process of speciation should be related to the south-to-north progression of uplift throughout the Andes. Other authors emphasized the possible role of a rapid uplift that occurred during the Late Miocene and Early Pliocene, but often without establishing clear links between dated divergences and local geologic events (e.g. Casner & Pyrcz 2010; Mulch et al. 2010; Matos-Maraví et al. 2013; Lagomarsino et al. 2016). From a geological point of view, the concept of a progressive, general south-to-north uplift is an oversimplified view of a much more complex reality (Sempere et al. 2008). In the Central Andes, palaeo-elevation histories differ not only between the south and the north, but also between the western and the eastern cordilleras, notably in northern Peru (Picard et al. 2008; Eude et al. 2015; Margirier et al. 2015). The idea that the Northern Andes, as a whole, uplifted later than the Central Andes, as suggested by Doan (2003), and often admitted by other authors, is not supported by geological studies that also demonstrate that the timing of palaeo-elevation differed between the three Colombian Cordilleras (Restrepo- Moreno et al. 2009). Consistent with many other examples, notably the clearwing Oleriina butterflies (De-Silva et al. 2016), the M. sulkowskyi group illustrates the diversity of diversification histories throughout the Andes. It also demonstrates that Mio-Pliocene orogenic and Pleistocene climatic diversification drivers should not be opposed.



Romain Nattier, Claire Capdevielle-Dulac, Catherine Cassildé, Arnaud Couloux, Corinne Cruaud, Gilbert Lachaume, Gerardo Lamas, Jean-François Silvain and Patrick Blandin. 2017. Phylogeny and Diversification of the Cloud Forest Morpho sulkowskyi Group (Lepidoptera, Nymphalidae) in the Evolving Andes.  Zoologica Scripta.  DOI: 10.1111/zsc.12226

   

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


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.

[PaleoMammalogy • 2017] Inermorostrum xenops • A Toothless Dwarf Dolphin (Odontoceti: Xenorophidae) Points to Explosive Feeding Diversification of Modern Whales (Neoceti) ---ScRaBBlE


Inermorostrum xenops
Boessenecker, Fraser, Churchill & Geisler, 2017


Abstract

Toothed whales (Odontoceti) are adapted for catching prey underwater and possess some of the most derived feeding specializations of all mammals, including the loss of milk teeth (monophyodonty), high tooth count (polydonty), and the loss of discrete tooth classes (homodonty). Many extant odontocetes possess some combination of short, broad rostra, reduced tooth counts, fleshy lips, and enlarged hyoid bones—all adaptations for suction feeding upon fishes and squid. We report a new fossil odontocete from the Oligocene (approx. 30 Ma) of South Carolina (Inermorostrum xenops, gen. et sp. nov.) that possesses adaptations for suction feeding: toothlessness and a shortened rostrum (brevirostry). Enlarged foramina on the rostrum suggest the presence of enlarged lips or perhaps vibrissae. Phylogenetic analysis firmly places Inermorostrum within the Xenorophidae, an early diverging odontocete clade typified by long-snouted, heterodont dolphins. Inermorostrum is the earliest obligate suction feeder within the Odontoceti, a feeding mode that independently evolved several times within the clade. Analysis of macroevolutionary trends in rostral shape indicate stabilizing selection around an optimum rostral shape over the course of odontocete evolution, and a post-Eocene explosion in feeding morphology, heralding the diversity of feeding behaviour among modern Odontoceti.

KEYWORDS: Xenorophidae, Odontoceti, Neoceti, suction feeding, Oligocene




Etymology. The generic name is from the Latin inermus, meaning weapon-less or defenceless, and rostrum, meaning snout, referring to the absence of teeth in the rostrum. The species name derives from Greek for strangexeno, and faceops, referring to the highly derived facial morphology of the holotype.


Robert W. Boessenecker, Danielle Fraser, Morgan Churchill and Jonathan H. Geisler. 2017. A Toothless Dwarf Dolphin (Odontoceti: Xenorophidae) Points to Explosive Feeding Diversification of Modern Whales (Neoceti). Proceedings of the Royal Society B. DOI: 10.1098/rspb.2017.0531

This ancient dwarf dolphin may have slurped its food like a walrus  sciencemag.org/news/2017/08/ancient-dwarf-dolphin-may-have-slurped-its-food-walrus

   

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
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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.

[Ornithology • 2017] Tapping the Woodpecker Tree for Evolutionary Insight ---ScRaBBlE



Shakya, Fuchs, Pons & Sheldon, 2017 

Highlights
• We compared DNA sequences of six loci from 203 of the 217 recognized species to construct a comprehensive tree of intrafamilial relationships of woodpeckers and found numerous unknown relationships among clades and species.
• We discuss how convergence, mimicry, and potential cases of hybridization obscured woodpecker relationships for morphological taxonomists.
• We also used the tree to analyze rates of diversification and biogeographic patterns within the family.

Abstract
Molecular phylogenetic studies of woodpeckers (Picidae) have generally focused on relationships within specific clades or have sampled sparsely across the family. We compared DNA sequences of six loci from 203 of the 217 recognized species of woodpeckers to construct a comprehensive tree of intrafamilial relationships. We recovered many known, but also numerous unknown, relationships among clades and species. We found, for example, that the three picine tribes are related as follows (Picini, (Campephilini, Melanerpini)) and that the genus Dinopium is paraphyletic. We used the tree to analyze rates of diversification and biogeographic patterns within the family. Diversification rate increased on two occasions during woodpecker history. We also tested diversification rates between temperate and tropical species but found no significant difference. Biogeographic analysis supported an Old World origin of the family and identified at least six independent cases of New World-Old World sister relationships. In light of the tree, we discuss how convergence, mimicry, and potential cases of hybridization have complicated woodpecker taxonomy.

Keywords: biogeography; convergence; diversification rates; phylogeny; Picidae; rate-shifts


Subir B. Shakya, Jérôme Fuchs, Jean-Marc Pons and Frederick H. Sheldon. 2017. Tapping the Woodpecker Tree for Evolutionary Insight. Molecular Phylogenetics and Evolution. In Press.  DOI: 10.1016/j.ympev.2017.09.005

New paper by #LSUMNS student Subir Shakya & Curator Fred Sheldon in MP&E. "Tapping the Woodpecker Tree for Evolutionary Insight" 

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


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.

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