A new adult specimen of the basalmost ornithuromorph bird Archaeorhynchus spathula (Aves: Ornithuromorpha) and its implications for early avian ontogeny

doi:10.1080/14772019.2015.1136968

	A new adult specimen of the basalmost ornithuromorph bird Archaeorhynchus spathula (Aves: Ornithuromorpha) and its implications for early avian ontogeny
	Wang, M (Wang, Min); Zhou, ZH (周忠和)
	2017
发表期刊	Journal of Systematic Palaeontology
ISSN	1477-2019
卷号	15 期号:1 页码:1-18
摘要	Most living birds characteristically grow rapidly and reach adult size within a year. Nevertheless, little is known about how such an advanced developmental strategy evolved despite many discoveries of early fossil birds. Here we assess the long-bone histology from a new adult specimen of Archaeorhynchus spathula, the basalmost taxon of Ornithuromorpha. Ornithuromorpha is the most inclusive clade containing extant birds but not the Mesozoic Enantiornithes. Histological analysis reveals that the cortex is composed of parallel-fibred bone with three lines of arrested growth, indicative of slow and annually interrupted growth for this taxon. Such bone histology is significantly different from that of other known basal ornithuromorphs, but resembles that of enantiornithines, which leads us to suggest protracted slow growth in the common ancestor of Ornithuromorpha and Enantiornithes. The fusion sequence of the tarsometatarsus between Enantiornithes and Ornithuromorpha has long been hypothesized to be different and regarded as indicative that enantiornithines are not close relatives of ornithuromorphs. Due to a lack of fossils recording early ontogenetic stages, little is known about the development of the tarsometatarsus in basal ornithuromorphs, making this hypothesis impossible to test. Here we show that the fusion sequence of the tarsometatarsus in Archaeorhynchus is similar to that of enantiornithines, and that the proximal-early fusion in tarsometatarsus represents a plesiomorphic trait for basal birds. Our findings also shed light on ontogenetic variation of sternal morphology, which highlights the importance of ontogeny in the taxonomic and phylogenetic study of early birds.
关键词	Aves Cretaceous histology ontogeny Ornithuromorpha tarsometatarsus
DOI	10.1080/14772019.2015.1136968
收录类别	SCI
语种	英语
WOS研究方向	Evolutionary Biology ; Paleontology
WOS类目	Evolutionary Biology ; Paleontology
WOS记录号	WOS:000390346400001
出版者	TAYLOR & FRANCIS LTD
文献类型	期刊论文
条目标识符	http://ir.nigpas.ac.cn/handle/332004/12786
专题	中国科学院南京地质古生物研究所
推荐引用方式 GB/T 7714	Wang, M ,Zhou, ZH . A new adult specimen of the basalmost ornithuromorph bird Archaeorhynchus spathula (Aves: Ornithuromorpha) and its implications for early avian ontogeny[J]. Journal of Systematic Palaeontology,2017,15(1):1-18.
APA	Wang, M ,&Zhou, ZH .(2017).A new adult specimen of the basalmost ornithuromorph bird Archaeorhynchus spathula (Aves: Ornithuromorpha) and its implications for early avian ontogeny.Journal of Systematic Palaeontology,15(1),1-18.
MLA	Wang, M ,et al."A new adult specimen of the basalmost ornithuromorph bird Archaeorhynchus spathula (Aves: Ornithuromorpha) and its implications for early avian ontogeny".Journal of Systematic Palaeontology 15.1(2017):1-18.