Oldest ctenodactyloid tarsals from the Eocene of China and evolution of locomotor adaptations in early rodents

doi:10.1186/s12862-018-1259-1

	Oldest ctenodactyloid tarsals from the Eocene of China and evolution of locomotor adaptations in early rodents
	Fostowicz-Frelik,?ucja 1,2; Li,Qian1 ; Ni,Xijun1
刊名	BMC Evolutionary Biology
	2018-10-04
卷号	18 期号:1
关键词	Glires Rodentia Paleogene Asia Foot structure Locomotion Morphological evolution
ISSN号	1471-2148
DOI	10.1186/s12862-018-1259-1
通讯作者	Fostowicz-Frelik,?ucja(lfost@twarda.pan.pl)
英文摘要	AbstractBackgroundTamquammys has been considered one of the basal ctenodactyloid rodents, which has been documented in the earliest to middle Eocene (~?56.0–48.5?Ma) in China. It was the most abundant and widespread rodent genus in the Erlian Basin (Nei Mongol, China) and dominated Arshantan small-mammal faunas of that region. Here for the first time we describe the morphology of the astragalocalcaneal complex in Tamquammys robustus (larger) and T. wilsoni, and interpret it against the background of locomotor adaptations of basal Euarchontoglires (rodents, lagomorphs, tree shrews, and primates).ResultsThe comparative morphology of the tarsal elements in Tamquammys robustus and T. wilsoni shows overall slenderness of the bones and their similarity to the tarsal elements of Rattus, a generalist species, and those of small rock squirrels (e.g. Sciurotamias). The two species differ slightly in their cursorial ability; smaller T. wilsoni shows some adaptations to climbing. The results of principal component analysis of the calcaneus and astragalus support this observation and place T. robustus in-between Rattus and ground/rock squirrel morphospace, and T. wilsoni closer to euarchontans, Tupaia and Purgatorius.ConclusionsThe morphology of the tarsal elements in Tamquammys indicates a generalist rodent morphotype with no particular adaptations to arboreality. We suggest that Tamquammys as a basal ctenodactyloid is closer to the ancestral astragalocalcaneal morphology of rodents than that of more derived North American paramyines of similar age. Overall similarity in Tamquammys tarsal elements structure to Purgatorius, a basal primate, may point to the antiquity of the tarsal structure in Tamquammys and a generally unspecialized foot structure in early Euarchontoglires.
语种	英语
出版者	BioMed Central
WOS记录号	BMC:10.1186/S12862-018-1259-1
内容类型	期刊论文
源URL	[http://119.78.100.205/handle/311034/8446]
专题	中国科学院古脊椎动物与古人类研究所
通讯作者	Fostowicz-Frelik,?ucja
作者单位	1. 2.
推荐引用方式 GB/T 7714	Fostowicz-Frelik,?ucja,Li,Qian,Ni,Xijun. Oldest ctenodactyloid tarsals from the Eocene of China and evolution of locomotor adaptations in early rodents[J]. BMC Evolutionary Biology,2018,18(1).
APA	Fostowicz-Frelik,?ucja,Li,Qian,&Ni,Xijun.(2018).Oldest ctenodactyloid tarsals from the Eocene of China and evolution of locomotor adaptations in early rodents.BMC Evolutionary Biology,18(1).
MLA	Fostowicz-Frelik,?ucja,et al."Oldest ctenodactyloid tarsals from the Eocene of China and evolution of locomotor adaptations in early rodents".BMC Evolutionary Biology 18.1(2018).