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| - In 1912, Osborn came up with a description of the fossil and a theory to its mummification: "After a natural death (in other words, not death by predators) the body lay exposed to the sun for a long time, perhaps on a sand bar or in a stream. The muscles and soft internal tissues became completely dried and shrunken while the skin, hardened and leathery, shrank around the limbs and was drawn down along the bones. In the stomach and abdominal areas the skin was drawn within the body cavity, while along the sides of the body and on the arms, it was formed into creases and folds. At some later date, the "mummy" may have been caught in a sudden flood and carried downstream and rapidly buried in fine sand and clay. A cast, or impression, of the skin formed in the sand before the skin and other
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| abstract
| - In 1912, Osborn came up with a description of the fossil and a theory to its mummification: "After a natural death (in other words, not death by predators) the body lay exposed to the sun for a long time, perhaps on a sand bar or in a stream. The muscles and soft internal tissues became completely dried and shrunken while the skin, hardened and leathery, shrank around the limbs and was drawn down along the bones. In the stomach and abdominal areas the skin was drawn within the body cavity, while along the sides of the body and on the arms, it was formed into creases and folds. At some later date, the "mummy" may have been caught in a sudden flood and carried downstream and rapidly buried in fine sand and clay. A cast, or impression, of the skin formed in the sand before the skin and other soft parts decayed. There is no remnant of the actual skin preserved only its imprint." AMNH 5060, the "Trachodon mummy" (so-called because it appears to be a fossil of a natural mummy), is now recognized as a specimen of E. annectens. It was found to have skin impressions over the snout, much of the neck and torso, and parts of the arms and legs. The tail and part of the legs eroded before collection, so these areas are unknown for the specimen. Additionally, some areas with skin impressions, such as sections associated with the neck ridge (see below) and hands, were accidentally removed during preparation of the specimen. The specimen is thought to have desiccated in a dry stream bed, probably on or near a point bar. The circumstances of the location and preservation of the body suggest that the animal died during a prolonged drought, perhaps from starvation. The desiccated carcass was eventually buried in a sudden flood, surrounded by sediment that had enough fine particles to make a cast of the epidermal structures. The epidermis was thin, and the scalation composed of small nonoverlapping scales, as seen in the Gila monster. Two general types of scales were present over most of the body: small pointed or convex tubercles, in diameter with no definite arrangement (ground tubercles); and larger, flat polygonal tubercles (pavement tubercles) typically less than in diameter, but up to over the forearm. The pavement tubercles were grouped into clusters separated by ground tubercles, with transitional scales between the two types. Over most of the body, the pavement tubercles were arranged in circular or oval clusters, while near the shoulder on the upper arm, they formed strips roughly parallel to each other and the shoulder blade. Generally, clusters were larger on the upper surfaces of the body and smaller on the underside. Clusters up to in length were present above the hips. The only impressions from the head came from the large opening for the nostrils. Instead of tubercle impressions, there were impressions of folded soft tissue, with a deeper area at the anterior end of the opening that may have been the approximate location of the nostril itself. The neck and back had a soft ridge or frill running down the midline, with a row of oval tubercle clusters arranged above the spines of the vertebrae. The total height of the ridge on AMNH 5060 is not known, nor the disposition of its upper border, as the upper extremity was prepared away. The ridge was at least tall, and was folded and creased to permit movement. Osborn proposed that it was tall enough for another row of clusters. The forearms had the largest tubercles, arranged in single large clusters that covered the leading surfaces. The hands were covered in small pavement tubercles in a soft-tissue structure than enclosed the three central fingers; not even the tips were exposed. Osborn interpreted this as a paddle for swimming. Robert T. Bakker later reinterpreted it as a soft-tissue pad for walking, analogous to that of a camel. Like the forearm, the shin had large tubercles. The scalation of the rest of the leg is not presently known, although impressions on a specimen of the crested hadrosaurid Lambeosaurus suggest that the thighs were under the skin of the body, like modern birds. The tail of AMNH 5060 was not present, but other specimens have filled in some details for that area. Skin impressions from a partial tail belonging to either Edmontosaurus or its close relative Anatotitan, recovered from the Hell Creek Formation of Montana, show a segmented ridge above the vertebrae. The ridge was about tall, with the segments being about long and high, spaced apart, with one segment to a vertebra. Another tail, this time pertaining to a juvenile E. annectens, had fossilized impressions including tubercles as well as previously unseen skin textures. These impressions included elliptical overlapping scales, grooved scales, and a "9 cm by 10 cm trapezoidal horn-like structure".
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![[RDF Data]](/fct/images/sw-rdf-blue.png)