Inferring locomotor behaviours in Miocene New World monkeys using finite element analysis, geometric morphometrics and machine-learning classification techniques applied to talar morphology


The talus is one of the most commonly preserved post-cranial elements in the platyrrhine fossil record. Talar morphology can provide information about postural adaptations because it is the anatomical structure responsible for transmitting body mass forces from the leg to the foot. The aim of this study is to test whether the locomotor behaviour of fossil Miocene platyrrhines could be inferred from their talus morphology. The extant sample was classified into three different locomotor categories and then talar strength was compared using finite-element analysis. Geometric morphometrics were used to quantify talar shape and to assess its association with biomechanical strength. Finally, several machine-learning (ML) algorithms were trained using both the biomechanical and morphometric data from the extant taxa to infer the possible locomotor behaviour of the Miocene fossil sample. The obtained results show that the different locomotor categories are distinguishable using either biomechanical or morphometric data. The ML algorithms categorized most of the fossil sample as arboreal quadrupeds. This study has shown that a combined approach can contribute to the understanding of platyrrhine talar morphology and its relationship with locomotion. This approach is likely to be beneficial for determining the locomotor habits in other fossil taxa.

In J. R. Soc. Interface 15, 20180520 (2018)
Thomas A. Püschel
Thomas A. Püschel
Leverhulme Early Career Fellow

I am a palaeoprimatologist and vertebrate palaeobiologist mainly focused on primate and mammalian evolution. My main interest is to study organismal evolution by reconstructing and comparing the palaeobiology of fossils to their living ecological relatives. In order to do this, I apply a combination of predictive modelling, 3D morphometrics, virtual biomechanical techniques, computational simulations, phylogenetic comparative methods, and fieldwork. I am currently collaborating on a diversity of projects that can be placed in the interface between biological anthropology, palaeontology, ecology and evolutionary biology, using cutting-edge informatic techniques. My Leverhulme Project has taken me to Gorongosa National Park, Mozambique, where I work together with the Paleo-Primate Project Gorongosa.