masahitt

• Love, Alan; Grabowski, Mark Walter; Houle, David; Liow, Lee Hsiang; Porto, Arthur Guimaraes Carvalho & Tsuboi, Masahito [Show all 8 contributors for this article] (2021). Evolvability in the fossil record. Paleobiology. ISSN 0094-8373. p. 1–24. doi: 10.1017/pab.2021.36. Full text in Research Archive Show summary

  Abstract The concept of evolvability—the capacity of a population to produce and maintain evolutionarily relevant variation—has become increasingly prominent in evolutionary biology. Paleontology has a long history of investigating questions of evolvability, but paleontological thinking has tended to neglect recent discussions, because many tools used in the current evolvability literature are challenging to apply to the fossil record. The fundamental difficulty is how to disentangle whether the causes of evolutionary patterns arise from variational properties of traits or lineages rather than being due to selection and ecological success. Despite these obstacles, the fossil record offers unique and growing sources of data that capture evolutionary patterns of sustained duration and significance otherwise inaccessible to evolutionary biologists. Additionally, there exist a variety of strategic possibilities for combining prominent neontological approaches to evolvability with those from paleontology. We illustrate three of these possibilities with quantitative genetics, evolutionary developmental biology, and phylogenetic models of macroevolution. In conclusion, we provide a methodological schema that focuses on the conceptualization, measurement, and testing of hypotheses to motivate and provide guidance for future empirical and theoretical studies of evolvability in the fossil record.

• Tsuboi, Masahito; Kopperud, Bjørn Tore; Syrowatka, Christine; Grabowski, Mark Walter; Voje, Kjetil L. & Pelabon, Christophe [Show all 7 contributors for this article] (2020). Measuring Complex Morphological Traits with 3D Photogrammetry: A Case Study with Deer Antlers. Evolutionary Biology. ISSN 0071-3260. 47, p. 175–186. doi: 10.1007/s11692-020-09496-9. Full text in Research Archive Show summary

  The increasing availability of 3D-imaging technology provides new opportunities for measuring morphology. Photogrammetry enables easy 3D-data acquisition compared to conventional methods and here we assess its accuracy for measuring the size of deer antlers, a complex morphological structure. Using a proprietary photogrammetry software, we generated 3D images of antlers for 92 individuals from 29 species of cervids that vary widely in antler size and shape and used these to measure antler volume. By repeating the process, we found that the relative error averaged 8.5% of object size. Errors in converting arbitrary voxel units into real volumetric units accounted for 70% of the measurement variance and can therefore be reduced by replicating the conversion. We applied the method to clay models of known volume and found no indication of bias. The estimation was robust against variation in imaging device, distance and operator, but approximately 40 images per specimen were necessary to achieve good precision. We used the method to show that conventional measures of main-beam length are relatively poor estimators of antler volume. Using loose antlers of known weight, we also showed that the volume may be a relatively poor predictor of antler weight due to variation in bone density across species. We conclude that photogrammetry can be an efficient and accurate tool for measuring antlers, and likely many other complex morphological traits.

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