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Biology subjects

Potvin, D. A.

Publications and source records attributed to Potvin, D. A..

2 recordsLinked to original sources

The future is faeces: Using faecal genomic sequencing to understand dietary choices of an endangered arboreal marsupial

1. Understanding critical components of habitat use, such as dietary preferences, is crucial for creating and implementing effective conservation plans. This becomes challenging when species exhibit cryptic behaviours, such as arboreality and nocturnality, as seen in the endangered greater glider (Petauroides spp). Existing methods for determining greater glider diet are inadequate, time consuming and prone to human error. Furthermore, current literature lacks specificity, with most research stating simply that greater gliders are dietary eucalypt specialists, without providing additional insight into which species are eaten. 2. Here, we tested a non-invasive technique using targeted sequencing of species-specific single nucleotide polymorphisms from greater glider faecal samples to identify dietary components across multiple locations in Southeast Queensland. 3. Sequencing identified 17 plant species present in the faecal samples, including Angophora, Acacia and Casuarina spp. that were previously unknown to be feed tree taxa, profoundly increasing our understanding of the habitat requirements of this endangered marsupial. Four of these identified species were out of range of their natural occurrence, suggesting limitations to the accuracy of this technique. 4. This study demonstrates the value of using genomic sequencing for analysing diets of arboreal mammals and makes recommendations for improving the accuracy of this methodology for future studies. Our findings highlight key tree species to be considered important for future greater glider conservation plans and raises the question whether there are local drivers behind the differences in dietary choices across the landscape. Such information will be critical for greater glider conservation, particularly when management planning across multiple habitats.

molecular biology↗

Islands promote diversification within the silvereye clade: a phylogenomic analysis of a great speciator

Geographic isolation plays a pivotal role in speciation by restricting gene flow between populations through distance or physical barriers. However, the speciation process is complex, influenced by the interplay between dispersal ability and geographic isolation, especially in "great speciators" - bird species present on multiple islands that, at the same time, have many subspecies. Comparing population differentiation in both continental and insular settings can help us to understand the importance of geographical context in the emergence of great speciators. The highly diverse white-eye family Zosteropidae includes several great speciators, including the silvereye (Zosterops lateralis) which consists of 16 subspecies, 11 occurring on islands. The distribution of the silvereye on the Australian continent and numerous southwest Pacific islands allows us to explore the influence of different forms of geographic isolation on population divergence. To do this, we conducted a comprehensive phylogenomic analysis of the silvereye and compared patterns of population divergence in insular versus continental silvereye populations. We estimate that the silvereye lineage emerged approximately 1.5 million years ago, followed by the split of the two main silvereye clades: Southern Melanesia and the broader South Pacific (encompassing Australia, New Zealand, and outlying islands). Continental populations show low genetic population structure, which suggests that they can overcome multiple forms of geographic barriers across long distances. In contrast, most island populations are highly structured even over relatively short distances. Divergence statistics further support the idea that water barriers lead to a higher population differentiation when compared to continental distances. Our results indicate that islands promote divergence and provide an empirical example of the geographical conditions that result in the emergence of great speciators.

evolutionary biology↗