临夏盆地晚中新世鸵鸟化石的特异保存
Exceptional preservation of an extinct ostrich from the Late Miocene Linxia Basin of China
A. photograph of the fragment prior to extraction, outlined in red; B. histological cross section of the fragment under transmitted light; C. close-up showing highly altered bone microstructure; D. higher magnification shows elongated, beige areas that correspond to bacterial colonies within a lighter and unaffected bone matrix; E. corresponding SEM image of (C); F. a close-up of the bacterial colonies under the SEM; G. Higher magnification shows that the colonies are characterized by thin channels and pores (bc); H. second histological cross section of the fragment, with high pneumaticity and little amounts of bone; I. close-up showing microbially attacked bone; J. close-up on another region showing unaltered bone (without any bacterial colonies) and a vascular canal in the center; K. close-up of the vascular canal shows it is filled with a brown material, most likely organic remnants, some round structures are also seen, and they present the right size and location to be the fossilized remnants of original red blood cells; L. close-up (slightly more dorsal) shows a hollow, tubular structure with walls. It presents all of the morphological characteristics of extant ostrich blood vessels and blood vessel walls (
All light microscopy photographs in this figure are shown under transmitted light Abbreviations: bc. bacterial colony; BOM. potential brown organic matter; BV. blood vessel (or fossilized remnants of original blood vessel); BVW. blood vessel wall (or fossilized remnants of original blood vessel wall); Cerv. cervical vertebra; OL. osteocyte lacuna; RBCs. red blood cells; ub. unaltered bone matrix; VC. vascular canal
