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Extant salamanders are used as modern analogs of early digit-bearing tetrapods due to general similarities in morphology and ecology, but the study species have been primarily terrestrial and relatively smaller when the earliest digit-bearing tetrapods were aquatic and an order of magnitude larger. Thus, we created a 3D computational model of underwater walking in extant Japanese giant salamanders (Andrias japonicus) using 3D photogrammetry and open-access graphics software (Blender) to broaden the range of testable hypotheses about the incipient stages of terrestrial locomotion. Our 3D model and software protocol represent the initial stages of an open-access pipeline that could serve as a "one-stop-shop" for studying locomotor function, from creating 3D models to analyzing the mechanics of locomotor gaits. While other pipelines generally require multiple software programs to accomplish the different steps in creating and analyzing computational models of locomotion, our protocol is built entirely within Blender and fully customizable with its Python scripting so users can devote more time to creating and analyzing models instead of navigating the learning curves of several software programs. The main value of our approach is that key kinematic variables (e.g. speed, stride length, and elbow flexion) can be easily altered on the 3D model, allowing scientists to test hypotheses about locomotor function and conduct manipulative experiments (e.g. lengthening bones) that are difficult to perform in vivo. The accurate 3D meshes (and animations) generated through photogrammetry also provide exciting opportunities to expand the abundance and diversity of 3D digital animals available for researchers, educators, artists, conservation biologists, etc. to maximize societal impacts. [ABSTRACT FROM AUTHOR]

Pre-Pleistocene fossils of Anolis lizards are rare, although 20 Miocene fossils preserved in amber from the island of Hispaniola have been reported on previously. Using light-microscopy and computed-tomography imaging, we studied a new amber fossil Anolis lizard from Hispaniola. The fossil is likely a juvenile and preserves a largely intact left forelimb, including both scales and skeletal elements, as well as some additional skin, skin impressions, and fragmentary skeletal elements from other parts of the body. Using measurements and lamella counts from the forelimb of the fossil and other juvenile anoles, discriminant function analysis and three Euclidean-distance criteria derived from a principal components analysis consistently support classification of the fossil as a member of the trunk ecomorph category, and those results, in combination with two scale characters preserved in the fossil, suggest that it is a member of the Anolis distichus series within the Ctenonotus clade. These results represent only the third case of a well-supported assignment of an Anolis fossil to the trunk ecomorph category and the first to the A. distichus series. They also highlight that such assignments can sometimes be inferred from highly incomplete fossils. [ABSTRACT FROM AUTHOR]