Does mutual sexual selection explain the evolution of head crests in pterosaurs and dinosaurs?

Lethaia, Journal Year: 2011, Volume and Issue: 45(2), P. 139 - 156

Published: Dec. 19, 2011

Cranial ornamentation is widespread throughout the extinct non-avialian Ornithodira, being present Pterosauria, Ornithischia and Saurischia. Ornaments take many forms, can be composed of at least a dozen different skull bones, indicating multiple origins. Many these crests serve no clear survival function it has been suggested that their primary use was for species recognition or sexual display. The distribution within Ornithodira form position suggest selection as key factor, although role latter often rejected on grounds an apparent lack dimorphism in species. Surprisingly, phenomenon mutual – where both males females are ornamented select mates ignored research fossil ornithodirans, despite rich history frequent expression modern birds. Here, we review available evidence functions ornithodiran cranial conclude presents valid hypothesis presence distribution. integration into future studies critical to our understanding ecology, evolution particularly questions regarding dimorphism.

Language: Английский

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Melanosome evolution indicates a key physiological shift within feathered dinosaurs

Nature, Journal Year: 2014, Volume and Issue: 507(7492), P. 350 - 353

Published: Feb. 12, 2014

Language: Английский

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A guide to the field of palaeo colour

BioEssays, Journal Year: 2015, Volume and Issue: 37(6), P. 643 - 656

Published: April 8, 2015

Melanin, and other pigments have recently been shown to preserve over geologic time scales, are found in several different organisms. This opens up the possibility of inferring colours colour patterns ranging from invertebrates feathered dinosaurs mammals. An emerging discipline is palaeo colour: plays an important role display camouflage as well integumental strengthening protection, which makes possible hitherto difficult task doing inferences about past ecologies, behaviours, organismal appearance. Several studies techniques presented last couple years that described ways characterize pigment patterns. Here, I will review available methods likely applications understand ecologies. A golden age colourized animals now dawning upon us, may elucidate nature ancient predator prey interactions structures. Also watch Video Abstract .

Language: Английский

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Topology of Feather Melanocyte Progenitor Niche Allows Complex Pigment Patterns to Emerge

Science, Journal Year: 2013, Volume and Issue: 340(6139), P. 1442 - 1445

Published: April 26, 2013

Color patterns of bird plumage affect animal behavior and speciation. Diverse are present in different species within the individual. Here, we study cellular molecular basis feather pigment pattern formation. Melanocyte progenitors distributed as a horizontal ring proximal follicle, sending melanocytes vertically up into epithelial cylinder, which gradually emerges feathers grow. Different form by modulating presence, arrangement, or differentiation melanocytes. A layer peripheral pulp further regulates pigmentation via patterned agouti expression. Lifetime cyclic regeneration resets for physiological needs. Thus, evolution stem cell niche topology allows complex patterning through combinatorial co-option simple regulatory mechanisms.

Language: Английский

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3D Camouflage in an Ornithischian Dinosaur

Current Biology, Journal Year: 2016, Volume and Issue: 26(18), P. 2456 - 2462

Published: Sept. 1, 2016

Countershading was one of the first proposed mechanisms camouflage [1Poulton E.B. The Colours Animals: Their Meaning and Use, Especially Considered in Case Insects.Second Edition. Kegan Paul, Trench, Trübner, 1890Crossref Google Scholar, 2Thayer A.H. law which underlies protective coloration.Auk. 1896; 13: 477-482Google Scholar]. A dark dorsum light ventrum counteract gradient created by illumination from above, obliterating cues to 3D shape [3Ruxton G.D. Speed M.P. Kelly D.J. What, if anything, is adaptive function countershading?.Anim. Behav. 2004; 68: 445-451Crossref Scopus (89) 4Caro T. Concealing coloration animals.Q. Rev. Biol. 2014; 89: 63Crossref 5Rowland H.M. From Abbott Thayer present day: what have we learned about countershading?.Philos. Trans. R. Soc. Lond. B Sci. 2009; 364: 519-527Crossref PubMed (64) 6Kiltie R.A. Testing Thayer's countershading hypothesis: an image processing approach.Anim. 1989; 38: 542-544Crossref (20) Because optimal varies strongly with environment [7Penacchio O. Lovell P.G. Cuthill I.C. Ruxton Harris J.M. Three-dimensional camouflage: exploiting photons conceal form.Am. Nat. 2015; 186: 553-563Crossref (15) 8Penacchio Orientation sun animals its interaction crypsis.Funct. Ecol. 29: 1165-1177Crossref (21) 9Allen W.L. Baddeley Scott-Samuel N.E. quantitative test predicted relationship between lighting environment.Am. 2012; 180: 762-776Crossref (41) Scholar], pigmentation patterns give clues animal's habitat. Indeed, comparative evidence ungulates [9Allen Scholar] shows that interspecific variation matches predictions: open habitats, where direct overhead sunshine dominates, a sharp dark-light color transition high up body evident; closed habitats (e.g., under forest canopy), diffuse dominates smoother dorsoventral gradation found. We can apply this approach extinct preservation fossil melanin allows reconstruction [10Vinther J. Briggs D.E.G. Clarke Mayr G. Prum R.O. Structural feather.Biol. Lett. 2010; 6: 128-131Crossref (94) 11Vinther Saranathan V. colour feathers.Biol. 2008; 4: 522-525Crossref (144) 12Li Q. Gao K.-Q. Meng J.A. Shawkey M.D. D'Alba L. Pei Ellison M. Norell M.A. Vinther Reconstruction Microraptor evolution iridescent plumage.Science. 335: 1215-1219Crossref 13Li Plumage dinosaur.Science. 327: 1369-1372Crossref (194) 14Lindgren Sjövall P. Carney R.M. Uvdal Gren Dyke Schultz B.P. Barnes K.R. Polcyn M.J. Skin provides convergent melanism marine reptiles.Nature. 506: 484-488Crossref (2) 15Zhang F. Kearns S.L. Orr P.J. Benton Zhou Z. Johnson D. Xu X. Wang Fossilized melanosomes Cretaceous dinosaurs birds.Nature. 463: 1075-1078Crossref (210) Here study exceptionally well-preserved specimen Psittacosaurus sp. Chinese Jehol biota [16Lingham-Soliar Plodowski integument Liaoning Province, China: taphonomy, epidermal ceratopsian dinosaur.Naturwissenschaften. 97: 479-486Crossref (33) 17Mayr Peters D.S. Vogel Bristle-like integumentary structures at tail horned dinosaur Psittacosaurus.Naturwissenschaften. 2002; 361-365Crossref (90) This countershaded underbelly tail, whereas chest more pigmented. Other resemble disruptive camouflage, chin jugal bosses on face appear dark. projected onto anatomically accurate life-size model order assess their experimentally. are compared measured radiance generated identical uniform gray versus illumination. These studies suggest inhabited habitat such as relatively dense canopy.Video AbstracteyJraWQiOiI4ZjUxYWNhY2IzYjhiNjNlNzFlYmIzYWFmYTU5NmZmYyIsImFsZyI6IlJTMjU2In0.eyJzdWIiOiI1ZjY4YzU2MWIyN2UxYzM0ZjNjNDJjZTFjMGMyNGNkYyIsImtpZCI6IjhmNTFhY2FjYjNiOGI2M2U3MWViYjNhYWZhNTk2ZmZjIiwiZXhwIjoxNjc4Nzc2NTM4fQ.Jc4lqatPBvlKeVolYxqGWFZuZ4uy4p6FjKkJMd77t9fwrKkbh7jRiSw0jPBlRMcvdisvqLDOocMnmWpg3pw1CygrOD9lEY2Mar7RN3cbYqFPCncJNZOiMwrOtR3ZDqSxjjlQVAv2sJlSM3z_lAC6DgKjNGfRO4L59S7cx53XyijXl1NU6R4DEUjWxbeUautxrFQvmdsOHei0516xovDToWGefBzWPGGOyyUNxuhh1bix3oNe-MciBOw3Dfe54VIbFeN61Y7T2__KVqS3VLL0n5JR6XrHW2NMeQcJKQKCdimBmVmghgSiruy9tqhWZJqkoSegCs4Z59t4MZdVijE4QQ(mp4, (144.74 MB) Download video

Language: Английский

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