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有一篇没见过的很好懂，讲一种动物的骨骼在一个沼泽区域被发现，科学家就在研究它怎么死的，第一段BBIBIBI说了一堆然后说这个东西死的时候这个区域还是池塘，不是它活动的区域，所以肯定是别的原因死的。有个题 问能推测出什么，我选的它水性不好=。=感觉凉了
第二段说是不是会被卡在沼泽里陷进去就死了，然后作者也反驳了说它就是沼泽活动的没那么傻，而且骨头发现的深度远大于这个体型的动物会陷进去的深度。 作者后来推测可能是因为什么地质作用（忘了）导致它死这了之后骨头沉下去什么的。有个题问作者态度，还有个问第二段在全文的作用是什么，我选的给可能出现的第三段做铺垫
Journal Article
The Overmyer Mastodon (Mammut americanum) from Fulton County, Indiana
Neal Woodman and Jon W. Branstrator
The American Midland Naturalist
Vol. 159, No. 1 (Jan., 2008), pp. 125-146
Published by: The University of Notre Dame
Stable URL: https://www.jstor.org/stable/20491317
Page Count: 22
The remains of the Overmyer Mastodon exhibited no evidence of weathering, rodent gnawing or carnivore chewing, nor any other indication that they had been exposed at or above the surface of the pond. Hence, it appears that the recovered skeletal elements were submerged and buried quickly, and they remained buried until excavation of the drainage ditch. The scattered pattern of remains generally was similar to the taphonomic patterns of mastodon skeletons described at Christensen Bog (Graham et al., 1983:18), the Wells Mastodon Site (Gooding and Ogden, 1964), the Orelton Farms Mastodon Site (Thomas, 1952) and other pond and bog sites (e.g., Hartnagel and Bishop, 1922). The distribution of remains at the Overmyer Mastodon Site suggests that much of the skeleton of the mastodon laid on its right side, possibly with the posterior lower than the anterior. Portions of the anterior and left limbs of the skeleton that were not recovered may have separated from the decomposing carcass and may be located in an unexpected portion of the former pond; they may have been subsequently redistributed by activities of mastodons or other animals; or they may have been removed by scavengers. It is also possible that some parts of the skeleton were in the main area of the drainage ditch and were removed or destroyed by the equipment excavating the ditch.
说在这一代沼泽地（忘了是以前是沼泽还是现在是沼泽）发现了某种动物的遗骸（Mo开头，绝对不是猛犸）。考古学家有两种看法，第一种是这哥们儿被是淹死在这儿的。但是大家觉得这太不靠谱，因为这种动物是能够适应(adapt)沼泽捕食环境的，所以不靠谱。 p2 其他人认为这个动物mired by swamp, 但是下面说了两个理由说不太可能， 1， 因为他们本来就是在这些地方的， 应该不会那么笨2，好像是说他的腿怎么怎么着
One cause of death that has been suggested for mastodons discovered in former wetland environments is that they drowned after breaking through a floating vegetation mat of a quaking bog (Holman, 1975, 2001). However, sedimentary and paleontological evidence indicates that the pond at the Overmyer Site was open water at the time the mastodon died. Another common scenario has mastodons becoming mired in the sediments of a small pond or swamp (e.g., Hartt. 1871; Clarke, 1908:45; Hartnagle and Bishop, 1922:1915, 1951, 1989; Goldthwait, 1952; Gooding and Ogden, 1965; Camp, 1981; Graham et al., 1983). Incidents involving modern African elephants becoming stuck in mud or drowning have been observed, although they are uncommon (Haynes, 1991). The wet areas that mastodons frequented may have provided abundant opportunities for becoming bogged down, but it seems most likely that an animal adapted for feeding in wetland environments (e.g., Hallin, 1983; Lepper et. al., 1991) generally would be able to avoid such a fate. Based on the depth and distribution of its remains, it seems unlikely that the Overmyer Mastodon was a victim of the muck. Five articulated right tarsals found during the excavation mark the final position of one hind foot in the pond bottom sediments. The dorsal articular surface of the astragalus was at 61 cm below the top of the sand layer. We estimate the total hind leg length (including fleshy foot pads) of this mastodon to have been ca. 161 cm. Given that the bottom of the loot (including flesh) extended 24 cm below the top of the astragalus, the bottom of the foot would have been at ca. 85 cm below the. sand layer. Assuming the sediment-water interface was at ca. 38 cm below the sand at the time the mastodon died (see Stratigraphy), its hind leg would have been mired in ca. 47 cm of pond mud, or less than half way up its lower leg. It seems plausible that a healthy animal would have to sink much further than mid-shin to become irretrievably stuck. If an animal did become so stuck that it could not extract itself; it may already have been weakened by other factors—starvation, injury, illness. More to the point, if the Overmyer Mastodon had simply become mired, more of the bones from this and the other limbs would have been buried and preserved in closer association with each other. Instead, the foot that was found was incomplete, indicating that the foot was not entire when it was finally buried. The generally disordered scattering of remains suggests the bones instead may have gradually come loose and sunk to the bottom of the pond from a floating carcass as it decomposed.
是原文吗？
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发表于 2018-8-14 08:52:35
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