Phylogeography, historical demography and systematics of the world's smallest pythons (Pythonidae, Antaresia)

In 'hot' pursuit: exploring the evolutionary ecology of labial pits in boas and pythons

The evolution of thermoreception in animals, particularly that of infrared (IR)-sensing pits in boas, pythons and pit vipers, is a fascinating area of sensory ecology. While numerous studies have focused on the molecular mechanisms of IR sensing in snakes, the broader ecological and evolutionary significance remains less explored. In this study, we examined the origins and evolutionary consequences of labial pits in boas and pythons using phylogenetic comparative methods. We analysed how various ecological and biological factors-such as hunting mode, diet, habitat, body size and biome-were correlated with the presence of pits, and whether this adaptation influenced diversification rates. Our findings revealed that labial pits evolved multiple times and showed strong associations with an arboreal habitat and endothermic diet, but we did not find a significant correlation between pits and hunting mode or any other ecological traits. Moreover, lineages with pits did not exhibit higher diversification rates. This research provides new insights into the eco-evolutionary role of heat-sensing pits, suggesting that the emergence of labial pits might have acted as a key innovation, significantly affecting the evolution of habitat use patterns and prey preference for pythons and boas.

Dragons in the tropics - Phylogeography and speciation in Diporiphora lizards and common geographic breaks in co-distributed taxa

Co-distributed taxa can respond both similarly or differently to the same climatic and geological events, resulting in a range of phylogeographic patterns across the region. Using a nested approach on a taxonomically diverse yet morphologically conservative group of agamid lizards, we first aimed to evaluate more precisely the extent of phylogeographic structuring within the genus. Then, focusing on four lineages within the more widespread species, we assessed the impact of biogeographic barriers on phylogeographic structuring and demographic history of species, comparing to patterns previously observed in co-distributed taxa. These species occur in the Australian Monsoonal Tropics, a vast tropical savanna system with high richness and endemism associated with environmental heterogeneity and past climate fluctuations. The employment of genomic data helped to determine the relationships between specific taxa that were previously difficult to place. We found a local influence of biogeographic and climatic breaks on population dynamics, analogous to other species. We detected high levels of population structure in the West Kimberley and Arnhem Plateau, which are already known for high endemism. However, we also highlighted unique lineages in areas that have been overlooked until recently, in the South Kimberley and West Top End. Climatic and geographical features in the Arnhem Plateau act as a soft barrier between populations in the east and west regions of the Top End. These observations reflect patterns observed for other vertebrates across this rich biome, indicating how climatic variation, species' ecology, and landscape features interact to shape regional diversity and endemism.

Evolutionary models demonstrate rapid and adaptive diversification of Australo-Papuan pythons

Lineages may diversify when they encounter available ecological niches. Adaptive divergence by ecological opportunity often appears to follow the invasion of a new environment with open ecological space. This evolutionary process is hypothesized to explain the explosive diversification of numerous Australian vertebrate groups following the collision of the Eurasian and Australian plates 25 Mya. One of these groups is the pythons, which demonstrate their greatest phenotypic and ecological diversity in Australo-Papua (Australia and New Guinea). Here, using an updated and near complete time-calibrated phylogenomic hypothesis of the group, we show that following invasion of this region, pythons experienced a sudden burst of speciation rates coupled with multiple instances of accelerated phenotypic evolution in head and body shape and body size. These results are consistent with adaptive radiation theory with an initial rapid niche-filling phase and later slow-down approaching niche saturation. We discuss these findings in the context of other Australo-Papuan adaptive radiations and the importance of incorporating adaptive diversification systems that are not extraordinarily species-rich but ecomorphologically diverse to understand how biodiversity is generated.

Plio–Pleistocene vicariance across arid Australia in the ‘Spiny Knob-tailed Geckos’ (

Across Australia’s monsoon tropics and vast arid zone isolated regions or ‘islands’ of upland or rocky habitat are home to disjunct populations of many taxa of plants and animals. Comparative analyses of lineages that occur across these habitat islands provide opportunities to understand when and how environmental change drove isolation and diversification across arid Australia. Here we present an analysis of mitochondrial genetic diversity across disjunct populations of geckos in the Nephrurus asper group. Dating analyses suggest that disjunct and genetically divergent populations spanning the northern half of Australia diverged through the Plio–Pleistocene. Based on the timing of divergence and current habitat associations we hypothesise that species in this lineage were isolated by the expansion of unsuitable arid-zone habitats from the late Pliocene onwards. Across most areas, these barriers appear to be sandy or stony deserts. However, in eastern Australia genetically divergent populations are separated by grassland on flat vertisol-dominated soils (‘blacksoils’), suggesting that these habitats also expanded during the late Pliocene aridification. Finally, we show that western Queensland populations formerly referred to N. asper are genetically divergent and diagnosable on the basis of colour pattern and, herein, recognise these populations as a distinct species. https://zoobank.org/urn:lsid:zoobank.org:pub:9508CAAA-D014-452D-A3DA-325851615FA7