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This study focuses on the Tianshifu Basin, eastern Liaoning, China, which is filled with Lower–Middle Jurassic fluviolacustrine sediments rich in macroplants. Our aim is to explore the continental climate features of the late Early Jurassic period. The composition of the Early–Middle Jurassic flora and the carbon isotopic ratios of organic matter, total organic carbon, total organic nitrogen and sulphur of the rock samples from the Changliangzi section (the upper part of the Lower Jurassic deposits) have been investigated. Based on the flora, eastern Liaoning was generally characterized by temperate and humid conditions during the Early–Middle Jurassic period, but with rising temperatures during late Early Jurassic time. The sediments of the Changliangzi section show a transformation from shallow-lake facies to deep-lake facies. A positive organic carbon isotope excursion correlates with the deepening of this palaeolake, considered to be caused by climate warming. The late Early Jurassic climate warming indicated by floral and isotopic evidence corresponds to the climatic events recorded elsewhere in marine and continental sequences during the Toarcian Age, the so-called Toarcian Anoxic event, and may be associated with enhanced global greenhouse warming. This study provides new continental data supporting global warming during the late Early Jurassic period. [ABSTRACT FROM AUTHOR]

Principal component analysis has been used to test for similarities in ecology and life habit between modern and fossil birds; however, the two main portions of the hind limb—the foot and the long bone elements—have not been examined separately. We examine the potential links between morphology, ecology, and phylogeny through a synthesis of phylogenetic paleoecological methods and morphospace analysis. Both hind limb morphologies and species' ecologies exhibit extreme phylogenetic clumping, although these patterns are at least partially explainable by a Brownian motion style of evolution. Some morphologies are strongly correlated with particular ecologies, while some ecologies are occupied by a variety of morphologies. Within the morphospace analyses, the length of the hallux (toe I) is the most defining characteristic of the entire hind limb. The foot and hind limb are represented on different axes when all measurements are considered in an analysis, suggesting that these structures undergo morphological change separately from each other. Early birds tend to cluster together, representing an unspecialized basal foot morphotype and a hind limb reliant on hip-driven, not knee-driven, locomotion. Direct links between morphology, ecology, and phylogeny are unclear and complicated and may be biased due to sample size (~60 species). This study should be treated as a preliminary analysis that further studies, especially those examining the vast diversity of modern birds, can build upon. [ABSTRACT FROM AUTHOR]