Biology subjects

Tsang, S. M.

Publications and source records attributed to Tsang, S. M..

4 recordsLinked to original sources

bioRxiv2026

Genetic introgression is a catalyst for diversification in an Old World fruit bat radiation

Genetic introgression, the exchange of genes between closely related species, was once thought to be rare and counterproductive to species differentiation until more recent evidence showed that introgression is pervasive in nature and may even facilitate the transfer of important functional traits among species. However, evidence for the role of introgression in facilitating speciation in natural systems is rare. In this study, we investigated the role of introgression in accelerating trait sharing and speciation in a poorly understood group of South and Southeast Asian fruit bats of the genus Cynopterus using genome-wide DNA from 93 individuals, including both fresh and historic museum specimens. We uncovered substantial new species level diversity within the genus and retrieved multiple strong signatures of complex genetic introgression, including two putative events of hybrid speciation within this radiation. In the genomic areas implicated in most of these introgression events, we identified a locus potentially linked to sperm integrity and fusion of egg and sperm. Further, we observed high between-species divergence in an area of the genome linked to skull development. The Cynopterus radiation augments a small but growing list of examples showing that genetic introgression - rather than forming an impediment against differentiation - is likely to boost and reinforce diversification processes, for example through the transfer of functional loci that may facilitate innovations. Our study also highlights the importance of museum collections in understanding cryptic diversity and speciation in complex biogeographic settings.

evolutionary biology↗

bioRxiv2025

Connections in the Dark: Social-Ecological Networks as a Promising Tool for Bat Conservation and One Health

Bats provide vital ecosystem services, including pest suppression and crop pollination. However, the increasing proximity of bats and humans is a growing conservation and public health concern with negative consequences for both sides. Mitigating these consequences requires integrative approaches like network science and the emerging field of social-ecological networks (SENs), which offer powerful tools to map and analyse complex social and ecological dynamics. Here, we synthesize how network approaches have been applied to bat research and conservation. Specifically, we: (i) assess the use of both ecological and social network analyses to study bats; (ii) identify network tools well-suited for SEN-based bat research; (iii) present a case study illustrating how SEN applications in bat research can inform conservation and One Health efforts; and, lastly, (iv) discuss key challenges and opportunities in using SENs to investigate the human-bat interface. Our review unveils a rise in network-based bat research from 2006 to 2020, followed by a post-pandemic decline. Nevertheless, across the 127 studies mapped by our review, only one applied an SEN lens. Finally, we suggest how applying some underexplored SEN tools to bat research could lead to novel perspectives, aiming to promote integrated strategies for the coexistence of bats and humans.

ecology↗

bioRxiv2020

Population genetic structure in the insular Ryukyu flying fox, Pteropus dasymallus

Small isolated populations are vulnerable to both stochastic events and the negative consequences of genetic drift. For threatened species, the genetic management of such populations has therefore become a crucial aspect of conservation. Flying foxes (Pteropus spp, Chiroptera) are keystone species with essential roles in pollination and seed dispersal in tropical and subtropical ecosystems. Yet many flying fox species are also of conservation concern, having experienced dramatic population declines driven by habitat loss and hunting. The Ryukyu flying fox (Pteropus dasymallus) ranges from Japan and Taiwan to the northern Philippines, and has undergone precipitous population crashes on several islands in recent decades. To assess population genetic structure and diversity in P. dasymallus, and its likely causes, we analyzed mitochondrial and microsatellite DNA. Both markers showed significant genetic differentiation among most island populations with patterns of isolation-by-distance. However, while mitochondrial haplotypes showed some mixing across the region, likely reflecting historical colonization and/or dispersal events, microsatellites markers showed clear subdivisions corresponding to the position of deep ocean trenches. The current distribution of P. dasymallus and its subspecific diversity therefore appears to have arisen through vicariance coupled with a long history of restricted gene flow across oceanic barriers. We conclude that isolated island subgroups should be managed separately, with efforts directed at reducing further declines.

ecology↗

bioRxiv2019

PI4K2β constrains non-canonical Wnt-PCP signalling and is localised by PAR-1 (MARK2/3) phosphorylation

Canonical Wnt signalling is critically important in embryonic cell-type specification and cancer, while non-canonical Wnt signalling is primarily implicated in physical morphogenesis, especially planar cell polarity (PCP). Both are modulated by the polarity kinase PAR-1 (MARK2/3). PAR-1 phosphorylates the Wnt transducer Dishevelled, but there is evidence that it exerts control through other targets. Here we describe an in vitro screen for new targets of PAR-1 in which we identified phosphatidyl-inositol-4-kinase-2-beta (PI4K2{beta}) as a substrate. Perturbation phenotypes and reporter assays in vivo show that PI4K2{beta} inhibits both canonical and non-canonical Wnt pathways, in contrast to PI4K2, which promotes canonical but does not affect non-canonical signalling. We show that PI4K2{beta} acts in Wnt-responding tissue, not in Wnt production or secretion. Subcellularly, PI4K2{beta} is cortically enriched, unlike PI4K2, and is basolateral in polarised cells. Mutation of the PAR-1 phosphorylation site of PI4K2{beta} mis-localises it and the endogenous core PCP protein, Vangl2. Our results reveal that PAR-1 interacts with the vertebrate PCP signalling pathway via PI4K2{beta}.

developmental biology↗