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Protomamíferos Y Mamíferos Mesozoicos De América Del Sur

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Protomamíferos Y Mamíferos Mesozoicos De América Del Sur José F. Bonaparte - Laura A. Migale PROTOMAMÍFEROS Y MAMÍFEROS MESOZOICOS de América del Sur Museo Municipal de Ciencias Naturales “Carlos Ameghino” Mercedes - Buenos Aires -Argentina PROTOMAMÍFEROS Y MAMÍFEROS MESOZOICOS de América del Sur PROTOMAMÍFEROS Y MAMÍFEROS MESOZOICOS de América del Sur José F. Bonaparte Laura A. Migale PROTOMAMÍFEROS Y MAMÍFEROS MESOZOICOS de América del Sur Autores: José F. Bonaparte y Laura A. Migale. Diseño gráfico: Mariano Masariche. Ilustración de tapa: Jorge Blanco. Fundación de Historia Natural Félix de Azara Departamento de Ciencias Naturales y Antropológicas CEBBAD - Instituto Superior de Investigaciones - Universidad Maimónides Hidalgo 775 P. 7º - Ciudad Autónoma de Buenos Aires (54) 11-4905-1100 int. 1228 / www.fundacionazara.org.ar Tercera edición Impreso en Argentina - 2015 Se ha hecho el depósito que marca la ley 11.723. No se permite la reproducción parcial o total, el almacenamiento, el alquiler, la transmisión o la transformación de este libro, en cualquier forma o por cualquier medio, sea electrónico o mecánico, mediante fotocopias, digitalización u otros métodos, sin el permiso previo y escrito del editor. Su infracción está penada por las leyes 11.723 y 25.446. El contenido de este libro es responsabilidad de su autor. Bonaparte, José Fernando, Protomamíferos mesozoicos de América del Sur / Bonaparte, José Fernando ; Laura Migale. - 3a ed ampliada. - Ciudad Autónoma de Buenos Aires : Fundación de Historia Natural Félix de Azara, 2015. 254 p. ; 24 x 17 cm. ISBN 978-987-3781-25-4 1. Paleontología. I. Migale, Laura II. Título CDD 560 PLRÓ OGO Esta nueva edición tiene dos motivaciones trascendentes para los temas paleobioló- gicos tratados que nos han parecido indispensables incorporarlos para mantener actua- lizadas las interpretaciones sobre el origen de los mamíferos ocurrido a fines del Triá- sico Superior y también incorporar descubrimientos recientes de nuevos mamíferos cretácicos de Patagonia. En el primer tema las revisiones recientes sobre los pequeños “protomamíferos” Brasilodontidae han modificado substancialmente interpretaciones anteriores sobre el supuesto grupo ancestral a los más antiguos mamíferos, lo cual ha jerarquizado aún más la compleja importancia filogenética del registro terápsidos sud- americanos relacionados, de una manera u otra al surgimiento de los mamíferos, tema en el cual los paleontólogos argentinos y brasileños han logrado comunicar hallazgos e interpretaciones de notable significación para este importante tema señalado. En cuanto a los mamíferos cretácicos se han producido algunos estudios sobre ha- llazgos no señalados en la primera edición de este libro, especialmente de un notable mamífero del Cenomaniano (Cretácico Superior de Río Negro), descubierto por el no- table sabueso paleontológico Dr. Sebastián Apesteguía y colaboradores en 2008 y recién publicado con toda la pompa editorial que merece ese notable espécimen por Guiller- mo Rougier y colaboradores en Nature (2011). Sin dudas este notable mamífero amplia el registro mamaliano del Cretácico Supe- rior hacia niveles previos a los mamíferos de Los Alamitos y de La Colonia con lo cual se vislumbra el comienzo de una secuencia biocronológica que ampliará en pocos años el historial mamaliano en estas latitudes del ex supercontinente de Gondwana. Finalmente los nuevos hallazgos del área jurásica de Cerro Cóndor en la Provincia de Chubut aportan muchas complejas evidencias para ser desarrolladas paso a paso por nuestros paleontólogos. También un notable hallazgo extra sudamericano realizado en el Cretácico Superior de Madagascar, lo citamos brevemente por su eventual significación paleobiogeográ- fica para evaluar mejor la historia biológica de los mamíferos del Cretácico Superior sudamericano. José F. Bonaparte ÍNDICE 7 CAPÍTULO 1 AnTECEDENTES GENERALES 17 CAPÍTULO 2 INTRODUCCIÓN A LOS PROTOMAMÍFEROS 21 CAPÍTULO 3 CINODONTES ANCESTRALES 27 CAPÍTULO 4 SUBCLADO GOMPHODONTA, FAMILIA TRAVERSODONTIDAE Y DIADEMODONTIDAE 45 CAPÍTULO 5 EL SUBCLADO GALESAURIA. SUS REPRESENTANTES EN AMÉRICA DEL SUR 59 CAPÍTULO 6 SUBCLADO BRASILODONTA: THITHELEDONTA (IN PART.) KEMP, 2005. LOS “ICTIDOSAURIA” 69 CAPÍTULO 7 CINODONTES TENTATIVAMENTE BRASILODONTIDAE 75 CAPÍTULO 8 SUBCLADO BRASILODONTA. FAMILIA BRASILODONTIDAE 91 CAPÍTULO 9 LA CAJA CEREBRAL DE Brasilitherium riograndensis 105 CAPÍTULO 10 LOS MAMÍFERAS JURÁSICOS DE AMÉRICA DEL SUR 111 CAPÍTULO 11 LOS MAMÍFEROS CRETÁCICOS DE AMÉRICA DEL SUR. CRETÁCICO INF. Vinceleste neuquenianus 131 CAPÍTULO 12 LOS MAMÍFEROS DEL CRETÁCICO SUPERIOR DE AMÉRICA DEL SUR 149 CAPÍTULO 13 MAMÍFEROS DE LOS ÓRDENES TRICONODONTA Y SYMMETRODONTA 163 CAPÍTULO 14 LOS MAMÍFEROS MERIDIOLESTIDA DEL CRETÁCICO SUPERIOR DE PATAGONIA 187 CAPÍTULO 15 ORDEN MERIDIOLESTIDA? FAMILIA? CASAMIQUELIDAE BONAPARTE 2002 195 CAPÍTULO 16 COMENTARIOS MÁS DESTACADOS 203 CAPÍTULO 17 LAS EXPLORACIONES 213 BIBLIOGRAFÍA PROTOMAMÍFEROS Y MAMÍFEROS MESOZOICOS DE AMÉRICA DEL SUR CAPÍTULO ANTECEDENTES GENERALES 1 Fig. 1-1. José F. Bonaparte y Don Victorino Herrera en el Co. Cacheuta trabajando en la extracción de un laberintodonte. n este capítulo presentamos una muy Ameghino, G. Burmeister, A. Cabrera, N. E breve reseña de una cantidad de fac- Cattoi, L. Kraglievich, R. Pascual, M. Dol- tores y hechos no sólo paleontológicos que gopol de Saenz, y A. Castellanos, se dedi- han condicionado y alentado la dedicación de JFB desde sus comienzos al presente. Fig. 1-2. Dr. Osvaldo Cuando en 1959 Osvaldo A. Reig organizó A. Reig. Organizó la la 1ª. Expedición Paleontológica a la locali- primera expedición dad fosilífera triásica de Ischigualasto, en la paleontológica Provincia de San Juan, comenzó a abrirse argentina a la rica un amplio, novedoso y fructífero horizonte localidad fosilífera en los estudios de paleovertebrados en Ar- de Ischibualasto gentina. en la provincia Tradicionalmente dedicados a los ma- de San Juan en míferos cenozoicos desde los años del Dr. 1959. Tomado de Francisco Javier Muñiz (1830 aprox.), los Wikipedia. pocos paleontólogos argentinos o radica- dos en Argentina, como Florentino y Carlos ANTECEDENTES GENERALES CAPÍTULO 1 7 PROTOMAMÍFEROS Y MAMÍFEROS MESOZOICOS DE AMÉRICA DEL SuR caron al estudio de los mamíferos cenozoi- terrestres de algunos de los períodos del cos. Asimismo, las diversas expediciones Mesozoico. paleontológicas del American Museum de Las expediciones de F. von Huene, de la New York, el Field Museum de Chicago, Universidad de Tubingen al Triásico del sur de la Princeton University de Philadelphia de Brasil (1928, 1935, etc.) son una excepción realizadas a Patagonia entre fines de siglo a ese enunciado, ya que culminaron con el XIX y principios del siglo XX, centraron el logro de una amplia colección (hoy en Tu- grueso de sus estudios y exploraciones en el bingen) y un extenso estudio publicado en Cenozoico de Argentina, atraídos por los re- Alemania entre 1935 y 1942. levantes descubrimientos y estudios de los El pleno funcionamiento del CONICET, hermanos Ameghino. Poca atención, com- creado en 1955, posibilitó las expediciones parativamente, se prestó al estudio de los paleontológicas organizadas por O. A. Reig vertebrados cretácicos, excepto aquellos de en 1959 y 1960, y su ulterior continuación Lydekker (1893), Smith Woodward (1896, anual bajo la dirección del autor, inicián- 1901) y von Huene (1929), propiciados por dose así trabajos metódicos y continuados el Museo de La Plata, los que revelaron la de la exploración e investigación de verte- potencial diversidad de las faunas terrestres brados tetrápodos mesozoicos en Argentina sudamericanas de esa época. y Brasil, los que se prolongaron hasta 2002, Para el Jurásico, sólo un estudio del Dr. incorporando trabajos conjuntos con los co- Ángel Cabrera de un saurópodo fragmenta- legas brasileros, Dr. Jorge Ferigolo, Mario rio de ese período (Cabrera, 1943), alertaba Costa Barberena y sus discípulos de la Uni- sobre la existencia de dinosaurios jurásicos versidad Federal de Río Grande do Sul diri- en este subcontinente. Y para el Triásico, gidos por el Dr. C. M. Schultz. también fue el Dr. A. Cabrera (1944) que La 1ra. expedición al Triásico de Ischigua- comunicó la presencia de “reptiles” mami- lasto dirigida por O. A. Reig en 1959 se orga- feroides, terápsidos, en el Triásico de San nizó desde la entonces Escuela de Ciencias Juan y de anfibios laberintodontes en el Naturales de la Universidad Nacional de Triásico de Mendoza. Tucumán, y conjuntamente desde la Fun- De tal modo, aún cuando existían eviden- dación M. Lillo de la misma Universidad. cias y estudios de vertebrados mesozoicos El entomólogo Dr. Abraham Willink que en nuestro país y en Brasil, no superaron dirigía esas reparticiones de la UNT., facili- la etapa inicial caracterizada por estudios tó y apoyó la iniciativa de O. A. Reig que, ocasionales resultantes de hallazgos aisla- aunque financiada por el Conicet, requería dos, sin un plan de continuidad destinado diversos aspectos logísticos para su realiza- a coleccionar y estudiar los vertebrados ción. El apoyo del Dr. Willink fue decisivo para la continuidad de esos planes paleon- Fig. 1-3. El Dr. tológicos. Ángel Cabrera La citada 1ª Expedición contó con la pre- fue el primer sencia de un avezado coleccionista de fó- científico del siles, el Sr. Galileo J. Scaglia, por entonces Museo de La Director del Museo Municipal de Ciencias Plata que dio Naturales de Mar del Plata, por el autor, que a conocer en ese tiempo estaba al frente del Museo de cinodontes Ciencias Naturales “Carlos Ameghino” de triásicos y Mercedes
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