Biology subjects

Prideaux, G.

Publications and source records attributed to Prideaux, G..

3 recordsLinked to original sources

bioRxiv2026

Contingency Inverts Mammalian Herbivore Evolution in Australia

The rise of Neogene herbivores with high-crowned (hypsodont) molar teeth has been viewed as a mostly predictable response to abrasive grazing diets. Using kangaroos, an isolated marsupial radiation, we show that the ancestral vertical slicing function of grazing kangaroo molars prompted heavy investment from the late Miocene in thickened enamel, rather than hypsodonty. Grazing kangaroo enamel thickness overlaps some robust hominins, evincing an eclectic, thick-enamelled grazer guild. The success of vertically-chewing marsupials contrasts with their placental counterparts, which were overwhelmingly replaced by transversely-chewing ungulates. This inversion is explained by the pre-grassland extinction of most transversely-chewing marsupials, and the crucial advent of thick enamel. These results challenge the determinism of the browser-grazer transition, and implicate extinction, and ensuing innovation, as causes of unpredictability in evolution.

paleontology↗

bioRxiv2024

Avian telencephalon and cerebellum volumes can be accurately estimated from digital brain endocasts

For studies of the evolution of vertebrate brain anatomy and potentially associated behaviours, reconstructions of digital brain endocasts from computed tomography scans have revolutionised our capacity to collect neuroanatomical data. However, measurements from digital endocasts must be validated as reflecting actual brain anatomy, which is difficult because the collection of soft tissue information through histology is laborious and time consuming. In birds, the reliability of digital endocast measurements as volume proxies for the two largest brain regions - the telencephalon and cerebellum - remains to be validated despite their use as proxies e.g. of cognitive performance or flight ability. We here use the largest dataset of histology and digital endocasts to date, including 136 species from 25 avian orders, to compare digital endocast surface area measurements with actual brain volumes of the telencephalon, cerebellum, and whole-brain endocast. Using linear and phylogenetically informed regression analyses, we demonstrate that endocast surfaces are strongly correlated with their brain volume counterparts for both absolute and relative size. This provides empirical support for using endocast-derived cerebellar and telencephalic surface areas in existing and future studies of living and extinct birds, with potential to expand to the dinosaur-bird transition in the future.

animal behavior and cognition↗

bioRxiv2018

Rapid Pliocene Diversification of Modern Kangaroos

AbstractDifferentiating between ancient and rapidly-evolved clades is critical for understanding impacts of environmental change on biodiversity. Australia possesses many aridity-adapted lineages, the origins of which have been linked by molecular evidence to late Miocene drying. Using dental macrowear and molar crown-height measurements spanning the past 25 million years, we show that the most iconic of Australias terrestrial mammals, true kangaroos and wallabies (Macropodini), diversified in response to Pliocene grassland emergence. In contrast, low-crowned short-faced kangaroos radiated into browsing niches as the late Cenozoic became more arid, contradicting the view that this was a period of global decline among browsers. Our results link warm intervals with bursts of diversification and undermine arguments attributing Pleistocene megafaunal extinction to aridity-forced dietary change.

paleontology↗