Countershading and Stripes in the Theropod Dinosaur Sinosauropteryx Reveal Heterogeneous Habitats in the Early Cretaceous Jehol Biota
2017; Elsevier BV; Volume: 27; Issue: 21 Linguagem: Inglês
10.1016/j.cub.2017.09.032
ISSN1879-0445
AutoresFiann M. Smithwick, Robert D. Nicholls, Innes C. Cuthill, Jakob Vinther,
Tópico(s)Animal Behavior and Reproduction
ResumoCountershading is common across a variety of lineages and ecological time [1Allen W.L. Baddeley R. Cuthill I.C. Scott-Samuel N.E. A quantitative test of the predicted relationship between countershading and lighting environment.Am. Nat. 2012; 180: 762-776Crossref PubMed Scopus (41) Google Scholar, 2Thayer A.H. The law which underlies protective coloration.Auk. 1896; 13: 124-129Crossref Google Scholar, 3Vinther J. Nicholls R. Lautenschlager S. Pittman M. Kaye T.G. Rayfield E. Mayr G. Cuthill I.C. 3D camouflage in an ornithischian dinosaur.Curr. Biol. 2016; 26: 2456-2462Abstract Full Text Full Text PDF PubMed Scopus (60) Google Scholar, 4Rowland H.M. From Abbott Thayer to the present day: what have we learned about the function of countershading?.Philos. Trans. R. Soc. Lond. B Biol. Sci. 2009; 364: 519-527Crossref PubMed Scopus (64) Google Scholar]. A dark dorsum and lighter ventrum helps to mask the three-dimensional shape of the body by reducing self-shadowing and decreasing conspicuousness, thus helping to avoid detection by predators and prey [1Allen W.L. Baddeley R. Cuthill I.C. Scott-Samuel N.E. A quantitative test of the predicted relationship between countershading and lighting environment.Am. Nat. 2012; 180: 762-776Crossref PubMed Scopus (41) Google Scholar, 2Thayer A.H. The law which underlies protective coloration.Auk. 1896; 13: 124-129Crossref Google Scholar, 4Rowland H.M. From Abbott Thayer to the present day: what have we learned about the function of countershading?.Philos. Trans. R. Soc. Lond. B Biol. Sci. 2009; 364: 519-527Crossref PubMed Scopus (64) Google Scholar, 5Cuthill I.C. Sanghera N.S. Penacchio O. Lovell P.G. Ruxton G.D. Harris J.M. Optimizing countershading camouflage.Proc. Natl. Acad. Sci. USA. 2016; 113: 13093-13097Crossref PubMed Scopus (28) Google Scholar]. The optimal countershading pattern is dictated by the lighting environment, which is in turn dependent upon habitat [1Allen W.L. Baddeley R. Cuthill I.C. Scott-Samuel N.E. A quantitative test of the predicted relationship between countershading and lighting environment.Am. Nat. 2012; 180: 762-776Crossref PubMed Scopus (41) Google Scholar, 3Vinther J. Nicholls R. Lautenschlager S. Pittman M. Kaye T.G. Rayfield E. Mayr G. Cuthill I.C. 3D camouflage in an ornithischian dinosaur.Curr. Biol. 2016; 26: 2456-2462Abstract Full Text Full Text PDF PubMed Scopus (60) Google Scholar, 5Cuthill I.C. Sanghera N.S. Penacchio O. Lovell P.G. Ruxton G.D. Harris J.M. Optimizing countershading camouflage.Proc. Natl. Acad. Sci. USA. 2016; 113: 13093-13097Crossref PubMed Scopus (28) Google Scholar, 6Penacchio O. Lovell P.G. Cuthill I.C. Ruxton G.D. Harris J.M. Three-dimensional camouflage: exploiting photons to conceal form.Am. Nat. 2015; 186: 553-563Crossref PubMed Scopus (15) Google Scholar]. With the discovery of fossil melanin [7Vinther J. A guide to the field of palaeo colour: Melanin and other pigments can fossilise: Reconstructing colour patterns from ancient organisms can give new insights to ecology and behaviour.BioEssays. 2015; 37: 643-656Crossref PubMed Scopus (79) Google Scholar, 8Vinther J. Briggs D.E. Prum R.O. Saranathan V. The colour of fossil feathers.Biol. Lett. 2008; 4: 522-525Crossref PubMed Scopus (144) Google Scholar], it is possible to infer original color patterns from fossils, including countershading [3Vinther J. Nicholls R. Lautenschlager S. Pittman M. Kaye T.G. Rayfield E. Mayr G. Cuthill I.C. 3D camouflage in an ornithischian dinosaur.Curr. Biol. 2016; 26: 2456-2462Abstract Full Text Full Text PDF PubMed Scopus (60) Google Scholar, 9Li Q. Gao K.-Q. Meng Q. Clarke J.A. Shawkey M.D. D'Alba L. Pei R. Ellison M. Norell M.A. Vinther J. Reconstruction of Microraptor and the evolution of iridescent plumage.Science. 2012; 335: 1215-1219Crossref PubMed Scopus (144) Google Scholar, 10Li Q. Gao K.-Q. Vinther J. Shawkey M.D. Clarke J.A. D'Alba L. Meng Q. Briggs D.E. Prum R.O. Plumage color patterns of an extinct dinosaur.Science. 2010; 327: 1369-1372Crossref PubMed Scopus (194) Google Scholar]. Applying these principles, we describe the pattern of countershading in the diminutive theropod dinosaur Sinosauropteryx from the Early Cretaceous Jehol Biota of Liaoning, China. From reconstructions based on exceptional fossils, the color pattern is compared to predicted optimal countershading transitions based on 3D reconstructions of the animal's abdomen, imaged in different lighting environments. Reconstructed patterns match well with those predicted for animals living in open habitats. Jehol is presumed to have been a predominantly closed forested environment [3Vinther J. Nicholls R. Lautenschlager S. Pittman M. Kaye T.G. Rayfield E. Mayr G. Cuthill I.C. 3D camouflage in an ornithischian dinosaur.Curr. Biol. 2016; 26: 2456-2462Abstract Full Text Full Text PDF PubMed Scopus (60) Google Scholar, 11Zhonghe Z. Evolutionary radiation of the Jehol Biota: chronological and ecological perspectives.Geol. J. 2006; 41: 377-393Crossref Scopus (116) Google Scholar, 12Barrett P.M. Hilton J.M. The Jehol Biota (Lower Cretaceous, China): new discoveries and future prospects.Integr. Zool. 2006; 1: 15-17Crossref PubMed Google Scholar], but our results indicate a more heterogeneous range of habitats. Sinosauropteryx is also shown to exhibit a "bandit mask," a common pattern in many living vertebrates, particularly birds, that serves multiple functions including camouflage [13Bortolotti G.R. Hill G. McGraw K. Natural selection and coloration: protection, concealment, advertisement, or deception.in: Bird Coloration. Volume 2. 2006: 3-35Google Scholar, 14Ficken R.W. Wilmot L.B. Do facial eye-stripes function in avian vision?.Am. Midl. Nat. 1968; 79: 522-523Crossref Google Scholar, 15Ortolani A. Spots, stripes, tail tips and dark eyes: predicting the function of carnivore colour patterns using the comparative method.Biol. J. Linn. Soc. Lond. 1999; 67: 433-476Crossref Google Scholar, 16Caro T. The adaptive significance of coloration in mammals.Bioscience. 2005; 55: 125-136Crossref Scopus (336) Google Scholar, 17Caro T. Contrasting coloration in terrestrial mammals.Philos. Trans. R. Soc. Lond. B Biol. Sci. 2009; 364: 537-548Crossref PubMed Scopus (111) Google Scholar, 18Caro T. The colours of extant mammals.Semin. Cell Dev. Biol. 2013; 24: 542-552Crossref PubMed Scopus (41) Google Scholar]. Sinosauropteryx therefore shows multiple color pattern features likely related to the habitat in which it lived. Our results show how reconstructing the color of extinct animals can inform on their ecologies beyond what may be obvious from skeletal remains alone.Video AbstracteyJraWQiOiI4ZjUxYWNhY2IzYjhiNjNlNzFlYmIzYWFmYTU5NmZmYyIsImFsZyI6IlJTMjU2In0.eyJzdWIiOiJkY2QzYWNjYjM1ZWQ1MDMzNzRmNDE4ZmE3ZDgwMGM5MSIsImtpZCI6IjhmNTFhY2FjYjNiOGI2M2U3MWViYjNhYWZhNTk2ZmZjIiwiZXhwIjoxNjc4MzU5OTc3fQ.pOzsDO3BTFcdgfdoZS5KUyAn3cEZk775DPp-wIXhmfMK7kMv3qFbYEetmb6vLSWamlYdy53Tyr3S58vCluzcGat-MVuzxQBz9qqI97QJkLXwoxksIJ5xb1ahPgkzSjUijGyzwW2rVBRWN9yMnLXV1X4jsJ2qldTjH4OyM2nHWOopaC6t1Q7sQlquuXQ2xB0oYlNje3vXB0EyAn2DhLBThNODW5b_4S2jh_SK-5zpDn17taonSZ_T5KheWX9PXS4bWL02GyW0SYT6MY_dCFXLeCJoUV-D7xuBbjTEPDTe5oiPCIPfXWjt2N6kCeuSLxX0W3MyP0HyB-DTB5hPxjEYtQ(mp4, (38.44 MB) Download video
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