Nouveaux articles sur Madagascar
The Mahajanga Basin Project, initiated in 1993 and centered in Upper Cretaceous strata of northwestern Madagascar, has
resulted in the discovery of some of the most complete, well-preserved, and significant specimens of Late Cretaceous
vertebrate animals from the Southern Hemisphere and indeed the world. Among the most important finds are various
specimens of crocodyliforms, non-avian dinosaurs, and mammals; these finds have the potential to provide key insights into the biogeographic and paleogeographic history of Gondwana. Madagascar has been physically isolated from Africa for over 160 million years and from all other major landmasses for more than 85 million years. The closest known relatives of many of the Late Cretaceous Malagasy taxa are penecontemporaneous forms from South America (primarily Argentina) and India, thus documenting a previously unrecognized high level of cosmopolitanism among Gondwanan vertebrates near the end of the Cretaceous. The family-level taxa that are shared among Madagascar, South America, and the Indian subcontinent are not known from penecontemporaneous horizons in mainland Africa, but it cannot yet be confidently determined if this is due to differential extinction, poor sampling, true absence (i.e., the taxa were never present on Africa), or some combination thereof. Nonetheless, currently available geologic and paleontologic data are most consistent with the Africa-first model, suggesting that Africa was the first of the major Gondwanan landmasses to be fully isolated prior to the Albian/Cenomanian boundary, and that its terrestrial vertebrate faunas became progressively more provincial during the Cretaceous, while those on other Gondwanan landmasses remained relatively cosmopolitan until the later stages of the Late Cretaceous.
http://rapidshare.de/files/32281590/mobt_93_02_178.pdf.html
D. W. Krause. 2006. Science with a social conscience: digging for dinosaurs and helping children in the land that time forgot. Annals of the Missouri Botanical Garden 93: 367-368.
pas de résumé mais j'ai mis les 2 premiers paragraphes
Madagascar has been good to us. In 1993, I led a reconnaissance expedition in search of Cretaceous dinosaurs, mammals, and other vertebrate animals to this, the fourth-largest island in the world. Not in my wildest dreams did I anticipate the fossil riches that we would find on that expedition, or on the seven field campaigns since. Many of our discoveries are documented in an article in this volume (see pp. 178–208).
What we also found, however, were some of the most abandoned and destitute people on the planet. Many of Madagascar's citizens, particularly in rural areas, do not know how to read or write and have never been seen by a doctor or dentist. Malnutrition is ubiquitous. Children, who are otherwise rail thin, have abdomens that are visibly distended, largely a result of protein deficiency but oftentimes also owing to endemic parasites that inhabit, multiply within, and thus enlarge spleens and livers. Malaria is rampant. Upper respiratory, diarrheal, and dental infections are common and, owing to the lack of access to basic hygiene and antibiotics, all too frequently fatal.
http://rapidshare.de/files/32281818/mobt_93_02_367.pdf.html
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Edité le 07/09/2006 à 18:24 par markvantomme
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