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Biology Articles » Developmental Biology » Animal Development » Toothed Embryo Of Mammoth Toothed Embryo Of MammothFor the first time, a well-preserved lower jawbone of a mammoth embryo is found by paleontologist E.N. Mashchenko and his colleagues in the Tomsk area. Judging from the size and structure of the bone, the embryo is from 14 to 16 weeks old, which is the last stage of its development (the pregnancy of mammoths as well as elephants lasts for almost two years, i.e., from 22 to 23 months). The size and configuration of alveoli (teeth sockets in the jawbone) of the baby mammoth are indicative of the presence of teeth with well-developed crowns and roots.
The research assistants from the Paleontological Institute of the Russian Academy of Sciences and the Paleontological Museum of the Tomsk State University found the jawbone of the mammoth embryo at the place called Krasny Yar. This is a steep-sloped right side of the Ob River. The beach is composed of alluvial deposits containing bones of ancient animals. These bones are washed out from the rocks on river sides. From this place, paleontologists have collected many remnants of large mammals including the recently found jawbone. All fossils found in the Krasny Yar are dated at the Pleistocene. To determine the geological age of the jawbone of the mammoth embryo more precisely, the scientists studied its coloration and the degree of fossilization. Most probably this embryo was carried by a female mammoth lived at the period between two last glacial epochs, so-called interglacial period, more than 200 thousand years ago. This is the first finding of mammoth embryo in Siberia, and the age of the object is outstandingly old. Earlier findings of mammoth bones come from ancient human settlements and have an age of only from 27 to 14 thousand years. The jawbone of the baby mammoth significantly differs from those of present-day baby elephants by the size and the structure. However, the most striking distinction is the presence of large and fully developed teeth, while modern baby elephants have their teeth undersized. In the Pleistocene epoch, climate was rather harsh and cold, and nutrition from the mother`s milk was probably insufficient to little mammoths. So, they needed to use their teeth from the age of about three months to eat grass and other things. At the present time, young Indian and African elephants live in much milder climates and do not need to chew coarse food to survive. Informnauka (Informscience) Agency. June 2002. rating: 0.00 from 0 votes | updated on: 16 Jan 2008 | views: 66 | |

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