A new microconchid tubeworm from the Lower Permian (Artinskian) of central Texas, USA
by Olev Vinn
Acta Palaeontologica Polonica 56, 785–791.
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Seen by: and 20 moreMorphological trends in the fossil pollen of Decodon and the paleobiogeographic history of the genus
2012
Fridgeir Grimsson, David K. Ferguson, Reinhard Zetter
International Journal of Plant Sciences
Molecular preservation of the pigment melanin in fossil melanosomes.
Fossil feathers, hairs and eyes are regularly preserved as carbonized traces comprised of masses of micrometre-sized... more Fossil feathers, hairs and eyes are regularly preserved as carbonized traces comprised of masses of micrometre-sized bodies that are spherical, oblate or elongate in shape. For a long time, these minute structures were regarded as the remains of biofilms of keratinophilic bacteria, but recently they have been reinterpreted as melanosomes; that is, colour-bearing organelles. Resolving this fundamental difference in interpretation is crucial: if endogenous then the fossil microbodies would represent a significant advancement in the fields of palaeontology and evolutionary biology given, for example, the possibility to reconstruct integumentary colours and plumage colour patterns. It has previously been shown that certain trace elements occur in fossils as organometallic compounds, and hence may be used as biomarkers for melanin pigments. Here we expand this knowledge by demonstrating the presence of molecularly preserved melanin in intimate association with melanosome-like microbodies isolated from an argentinoid fish eye from the early Eocene of Denmark.
El concepto de extinción en el Cuaternario
Realizado con Joan Femenias Gual
Resumen. La extinción de las especies es uno de los temas que más bibliografía ha generado en los estudios de... more
Resumen. La extinción de las especies es uno de los temas que más bibliografía ha generado en los estudios de Cuaternario. Es un acontecimiento normal de la historia biológica, con una especial significación en el Pleistoceno. La actual extinción de especies es un tema de gran repercusión social, lo que acrecenta los esfuerzos dedicados a su investigación. Este artículo se centra en el concepto de extinción en el Cuaternario, sus causas y su especial significación para la investigación. Un profundo estudio de las extinciones puede ser una importante fuente de hipótesis para las investigaciones prehistóricas.
Abstract. The extinction of the species is one of the topics that have created more bibliography within the Quaternary studies. The extinction, a normal event of biological history, holds a special meaning in the Pleistocene. The current extinction is a topic of great social repercusion, which increases the efforts dedicated to its investigation. This paper aims to understand the concept of extinction in the Quaternary, its causes and its special meaning for investigation. Finally, a detailed study of the extinction may be an important source of hypothesis for Prehistory studies.
Bite marks of a large theropod on an hadrosaur limb bone from Coahuila, Mexico
Published in "Boletín de la Sociedad Geológica de Mexico"
Are described theropod bite marks on an hadrosaurine ornithopod tibia from Coahuila, Mexico Are described theropod bite marks on an hadrosaurine ornithopod tibia from Coahuila, Mexico
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