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Did Crocodiles Become Secondarily Ectothermic?

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Did Crocodiles Become Secondarily Ectothermic? Did crocodiles become secondarily ectothermic ? : a paleohistological approach Lucas Legendre To cite this version: Lucas Legendre. Did crocodiles become secondarily ectothermic ? : a paleohistological approach. Ver- tebrate Zoology. Université Pierre et Marie Curie - Paris VI, 2014. English. NNT : 2014PA066307. tel-01205158 HAL Id: tel-01205158 https://tel.archives-ouvertes.fr/tel-01205158 Submitted on 25 Sep 2015 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Université Pierre et Marie Curie École doctorale 398 : Géosciences, ressources naturelles et environnement Institut des Sciences de la Terre de Paris (ISTeP) - UMR 7193 Équipe Biominéralisation et environnements sédimentaires Les crocodiles sont-ils devenus secondairement ectothermes ? Étude paléohistologique Par Lucas LEGENDRE Thèse de doctorat de Paléontologie Dirigée par Jorge CUBO Présentée et soutenue publiquement le 23/09/2014 Devant un jury composé de : Kevin PADIAN Professeur UCMP, Berkeley Rapporteur Philippe JANVIER Directeur de recherche CNRS, Paris Rapporteur Francisco ORTEGA Professeur associé UNED, Madrid Examinateur Romain AMIOT Chargé de recherche CNRS, Lyon Examinateur Alexandra HOUSSAYE Chargée de recherche CNRS, Paris Examinatrice Yves DESDEVISES Professeur UPMC, Banyuls-sur-Mer Examinateur Damien GERMAIN Maître de conférences MNHN, Paris Invité Jorge CUBO Professeur UPMC, Paris Directeur de la thèse !" " A toi, lecteur aventureux en quête de savoir, qui peut-être un jour tombera sur ces pages jaunies par le temps. Puisses-tu y trouver quelque réconfort ! ‘Palaeohistology now stands as a powerful tool to reconstruct fossil vertebrates as living organisms, and accordingly, it is becoming a more and more popular approach for the more palaeobiologically-oriented students of vertebrate evolution.’ Armand de Ricqlès ‘It is paradoxical, yet true, to say, that the more we know, the more ignorant we become in the absolute sense, for it is only through enlightenment that we become conscious of our limitations. Precisely one of the most gratifying results of intellectual evolution is the continuous opening up of new and greater prospects.’ Nikola Tesla 2 Remerciements En premier lieu, merci à mon directeur de thèse, Jorge Cubo. Depuis déjà plus de trois ans que nous partageons les joies et les peines de l’étude de toutes ces coupes histologiques et autres méthodes statistiques, et ç’a été un vrai plaisir. Tu es l’une des personnes les plus patientes, dévouées et passionnées que j’ai pu rencontrer dans ma vie. Encore merci pour tout. Merci à toute l’équipe des irréductibles histologistes de Paris VI, en particulier Armand de Ricqlès, dont la réputation de légende vivante (devrais-je dire grand maître Jedi ?) de l’histologie osseuse est encore bien en dessous de la réalité ; Hayat Lamrous, pour sa disponibilité et son expertise technique irréprochable ; et Laetitia Montes, pour m’avoir permis d’accéder à son incroyable échantillonnage. Alexandra, Louise, nous n’avons pas eu l’opportunité de travailler ensemble, mais qui sait, ce n’est peut-être que partie remise ! Merci à Marc de Rafélis, à Loïc Segalen et à l’ensemble de l’équipe Biominéralisations. Bien que n’ayant qu’un lien scientifique très indirect avec vos travaux, j’ai pu constater le professionnalisme et la bonne ambiance qui règnent dans l’équipe au cours de mon séjour « chez les géologues ». Marc, c’est aussi à toi que je dois la suggestion de faire de l’enseignement, je ne te remercierai jamais assez de l’avoir faite. Un grand merci à Élodie Boucheron-Dubuisson et Sidney Delgado ainsi qu’à toute l’équipe du LV102, qui m’auront permis de faire mes preuves en tant que chargé de TD et de TP face à des hordes d’étudiants à peine plus jeunes que moi (et c’est un euphémisme). Ce fut une sacrée aventure, et je regrette qu’elle se soit terminée de façon aussi abrupte. Un jour, je l’espère, la biologie des organismes et l’étude de l’évolution seront de nouveau reconnues comme les disciplines indispensables qu’elles devraient encore être en licence de biologie dans la plus grande université française. Your move, mister president! Merci aussi à Julien Gasparini et à l’ensemble de l’équipe du LV373 pour avoir accueilli en catastrophe un pauvre paléontologue privé d’enseignement et l’avoir converti, tant bien que mal, à l’écologie évolutive. Cette UE est vraiment bien construite, et je suis content d’avoir pu en faire partie pour cette courte année 2014. Merci à Michel Laurin et à Yves Desdevises ; le premier pour m’avoir « offert » ma première publication avec beaucoup de courtoisie, le second pour ses précieux conseils en matière de méthodes phylogénétiques comparatives, et tous deux pour un comité de thèse complètement improvisé qui s’est avéré aussi intéressant que haut en couleurs (et tant mieux si Pénélope a bien aimé les dinosaures). Merci à Guillaume Guénard pour son aide (le mot est faible) sur la construction de mes modèles prédictifs – quelle connaissance de R ! – et à Pierre Legendre (aucun lien de parenté !) pour nous avoir mis en contact. Au plaisir de collaborer de nouveau sur un autre projet ! Un grand merci à Jennifer Botha-Brink pour ses échantillons d’archosauromorphes fossiles et pour nos longs échanges sur la taille de notre échantillonnage. Là aussi, ce n’est peut-être que le début d’une plus grande aventure… En vrac pour ne pas trop m’étendre, merci à : Holly Woodward et l’ensemble du comité d’organisation de l’ISPH 2013, pour ce merveilleux congrès au fin fond du Montana ; Cary Woodruff et toute la bande de fouilleurs passionnés avec qui j’ai passé dix jours de folie 3 à déterrer des sauropodes au milieu du désert ; Jérôme Sueur et tous ceux qui m’ont aidé dans ma longue découverte de R ; Gaëlle Boutin, la meilleure secrétaire de toute l’UPMC, et le personnel de la défunte école doctorale Diversité du Vivant (ah, Roscoff…) ; Estelle Bourdon, grande prétresse de l’ornithologie et co-auteur particulièrement prolifique ; René Zaragüeta i Bagils, Santiago Aragon et toute la « bande des espagnols », pour nos passionnantes discussions sur tout et n’importe quoi ; Eli Amson et toute l’équipe du BDEM, pour m’avoir invité à faire une présentation à leur congrès ; Kevin Padian et Damien Germain, pour s’être spontanément proposés pour être membres de mon jury de thèse, ainsi que Alexandra Houssaye, Francisco Ortega, Philippe Janvier et Romain Amiot pour avoir accepté d’en faire partie ; Régine Vignes-Lebbe, Pascal Tassy, Véronique Barriel et toute l’équipe pédagogique du Master SEP, qui m’a tant appris aussi bien sur le plan scientifique qu’humain, et sans qui je ne serai jamais arrivé jusqu’à la thèse. Merci à mes parents et à ma sœur, qui bien que ne comprenant pas toujours en quoi consiste exactement mon travail au quotidien m’ont toujours encouragé et soutenu durant toutes ces années. Je ne suis pas toujours très expansif sur le sujet, mais à votre façon vous m’avez énormément aidé. Merci à tous les membres (ils sont désormais trop nombreux pour tous les citer) de la plus si secrète Confrérie des Francs-Taxons, qui en aura surpris et intrigué beaucoup, mais qui malgré son caractère humoristique initial a fait beaucoup plus pour la communication entre étudiants passionnés de systématique et d’évolution que n’importe qui ne l’aurait imaginé au départ. Déjà cinq ans maintenant que les quatre étudiants un peu dingues et idéalistes que nous étions avons fondé ce projet délirant, et je n’ai jamais eu à le regretter. Vous êtes tous des gens géniaux, et vous m’avez apporté tellement que j’ai du mal à réaliser la chance que j’ai de tous vous connaître. Cladistique, VAVE, 3IA ! Et enfin, merci à Houda, qui m’a accompagné durant tout ce temps sans jamais rien demander en retour. Il ne doit pas être facile de vivre avec un doctorant, donc, plus que jamais, merci d’avoir supporté toutes les hésitations sur mon travail et tout le reste. Rendez- vous après la soutenance, et, promis, on pourra enfin se reposer un peu. 4 Sommaire Remerciements ........................................................................................................................... 3 Sommaire ................................................................................................................................... 5 Introduction ................................................................................................................................ 6 Partie I – Le signal phylogénétique dans la variation des caractères ostéohistologiques ........ 15 I – 1. Phylogenetic signal in bone histology of amniotes revisited ................................ 16 Introduction ........................................................................................................... 17 Material and methods ............................................................................................ 18 Results ................................................................................................................... 27 Discussion ............................................................................................................
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