A grazing Gomphotherium in Middle Miocene Central Asia, 10 million years prior to the origin of the Elephantidae.
A grazing Gomphotherium in Middle Miocene Central Asia, 10 million years prior to the origin of the Elephantidae.
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中亚中新世中期的食草嵌齿兽，比象科起源早 1000 万年
DOI：
10.1038/s41598-018-25909-4
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发表时间：
2018-05-16
影响因子：
4.6
通讯作者：
Wang SQ
中科院分区：
文献类型：
--
作者：
Wu Y;Deng T;Hu Y;Ma J;Zhou X;Mao L;Zhang H;Ye J;Wang SQ
化石植食性哺乳动物的食性是哺乳动物与植物生态系统共同进化的重要研究内容。本文对产于中亚准噶尔盆地中中新世的两个楔齿兽长鼻类化石中的植硅体进行了鉴定，表明楔齿兽属（Gomphotheriumconnexum）为混合食性动物，而楔齿兽属（G. steinheimense指示放牧偏好。这是已知最早的长鼻龙，主要有吃草的习惯。这些结果进一步证实了微磨损和同位素分析。花粉记录显示，在中中新世气候适宜期，亚洲内陆地区处于一个开放的干草原环境，树木稀少，这可能促使G.施泰因海姆人形态学和分支系统学分析表明，G. steinheimense包括四头象属gomphotheres的姐妹分类单元，它们被认为是衍生的“真象”的一般祖先种群; connexum在摄食行为和牙齿形态上都代表了一个更保守的谱系，随后完全灭绝。因此，放牧G. Steinheimense可能是一种适应干旱的行为，并允许其谱系进化出新的形态特征，以便在以后的时间里生存。这项研究显示了一个有趣的例子，行为适应形态修改之前。
Feeding preference of fossil herbivorous mammals, concerning the coevolution of mammalian and floral ecosystems, has become of key research interest. In this paper, phytoliths in dental calculus from two gomphotheriid proboscideans of the middle Miocene Junggar Basin, Central Asia, have been identified, suggesting that Gomphotherium connexum was a mixed feeder, while the phytoliths from G. steinheimense indicates grazing preference. This is the earliest-known proboscidean with a predominantly grazing habit. These results are further confirmed by microwear and isotope analyses. Pollen record reveals an open steppic environment with few trees, indicating an early aridity phase in the Asian interior during the Mid-Miocene Climate Optimum, which might urge a diet remodeling of G. steinheimense. Morphological and cladistic analyses show that G. steinheimense comprises the sister taxon of tetralophodont gomphotheres, which were believed to be the general ancestral stock of derived “true elephantids”; whereas G. connexum represents a more conservative lineage in both feeding behavior and tooth morphology, which subsequently became completely extinct. Therefore, grazing by G. steinheimense may have acted as a behavior preadaptive for aridity, and allowing its lineage evolving new morphological features for surviving later in time. This study displays an interesting example of behavioral adaptation prior to morphological modification.
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影响因子：
--
作者：
Hardy, Karen;Buckley, Stephen;Rosas, Antonio
通讯作者：
Rosas, Antonio
DOI：
10.1073/pnas.1016868108
发表时间：
2011-01-11
影响因子：
11.1
作者：
Henry, Amanda G.;Brooks, Alison S.;Piperno, Dolores R.
通讯作者：
Piperno, Dolores R.
影响因子：
10
作者：
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通讯作者：
Janis, Christine M.
影响因子：
2.2
作者：
Saegusa, H;Thasod, Y;Ratanasthien, B
通讯作者：
Ratanasthien, B
影响因子：
--
作者：
Calandra, Ivan;Goehlich, Ursula B.;Merceron, Gildas
通讯作者：
Merceron, Gildas