The representation of animal behaviour in the fossil record

Abstract

Paleontologists and biologists generally utilize different lines of evidence and approaches to study, conceptualize and categorize animal behaviour, which has led to a divide between the two disciplines and lack of integration of their data. Numerous filters impact the preservation of behaviour in the fossil record. Here, we utilize 13 broad categories of behaviour representing the range of modern studies of animal behaviour and assess how they are represented in the fossil record. The data summarized in an existing compilation of ‘fossil behaviours’ is used to estimate the relative occurrence of each category. We also examine the taxonomic coverage of fossil animal behaviour using the same source. We found that feeding and habitat selection-related behaviours were disproportionately represented. Examples of other behavioural categories, especially social ones, such as mating, communication or parenting were considerably rarer, whereas personality or play were not represented at all. Arthropods tended to be most well represented, including insects in amber, followed by vertebrates. Taxonomic coverage was overall fairly diverse. A broader literature search was used to identify the oldest paleontological evidence of each behavioural category. We found that most categories probably appeared by the end of the Cambrian radiation. Finally, we suggest that the preservation of behaviour in fossils can be estimated from first principles, such as the amount of time animals engage in a behaviour or which behaviours impact a substrate. Reconstructing the evolution of behaviour in deep time requires understanding how the fossil record captures behavioural information. We strongly encourage paleontologists and biologists studying behaviour to work together to help complete our understanding of animal behaviour across the entirety of its evolutionary history. • The fossil record of behaviour in deep time richly complements the modern. • A diversity of behaviours is represented in the paleontological literature. • Surveying this record can reveal how behaviours originated and evolved over time. • Understanding how behavioural evidence preserves is important for this goal.