Biology subjects

Liao, B.-Y.

Publications and source records attributed to Liao, B.-Y..

3 recordsLinked to original sources

bioRxiv2025

White eye-rings coevolved with diurnal behaviors as a trait enhancing visual appeal in rodents

Conspicuous colorations are widespread in animals, yet their adaptive functions remain unclear, particularly in mammals. White eye-rings (WER), the bright-colored pelage encircling eyes, are prevalence in rodents (Mammalia: Rodentia). Phylogenetic analyses across 601 rodents show that WER has repeatedly emerged with transitions to diurnalism and disappeared with reversions to nocturnalism during rodent evolution. To explore WERs function, we performed behavioral tests on the Nile rat (Arvicanthis niloticus, diurnal with WER) and the house mouse (Mus musculus, nocturnal without WER), and found that WER enhances visual appeal (the ability to attract attention or preference), likely by accentuating facial bilateral symmetry. This effect is neither associated with sexual selection nor species recognition and was absent in mice. Thus, WER appears selectively favored in diurnal rodents capable of perceiving and responding to it, but is constrained in nocturnal species. These findings illustrate how ecological factors and shared sensory preferences shape conspicuous color patterns.

evolutionary biology↗

bioRxiv2025

Natural variation in pigmentation caused by cis-regulatory changes affecting expression of the ebony gene in Drosophila elegans

Repetitive evolution has offered valuable insights into how similar traits can arise across different populations and species. The dimorphic body color morphs (brown and black) of geographically isolated Drosophila elegans Bock & Wheeler, 1972, along with its closely related species Drosophila gunungcola Sultana et al., 1999, which exhibits black morph, raise intriguing questions about whether these traits have emerged through independent evolution, introgression, or shared ancestral variants. To investigate the genetic and evolutionary origins of these differences, we perform quantitative trait locus (QTL) mapping on recombinant hybrids generated from reciprocal crosses between brown and black morphs D. elegans. QTL mapping reveals significant contributions from the X chromosome and Muller element E to intraspecific pigmentation polymorphism, with ebony identified as one candidate gene. Analysis of ebony expression, including allele-specific expression in F1 hybrids, and sequence variation suggests that the intra- and interspecific pigmentation differences within D. elegans species subgroup may have evolved independently from the lineage-specific region upstream of ebony. By identifying a shared candidate regulatory region associated with both intra- and interspecific variation, our findings suggest that recurrent use of the same genetic region may contribute to the emergence of similar traits across populations and species.

evolutionary biology↗

bioRxiv2020

Comparative transcriptomics across nematode life cycles reveal gene expression conservation and correlated evolution in adjacent developmental stages

Nematodes are highly abundant animals with diverse habitats and lifestyles. Some are free-living while others parasitize animals or plants, and among the latter, infection abilities change across developmental stages to infect hosts and complete life cycles. Although parasitism has independently arisen multiple times over evolutionary history, common pressures of parasitism--such as adapting to the host environment, evading and subverting the host immune system, and changing environments across life cycles--have led phenotypes and developmental stages among parasites to converge. To determine the relationship between transcriptome evolution and morphological divergences among nematodes, we compared 48 transcriptomes of different developmental stages across eight nematode species. The transcriptomes were clustered broadly into embryo, larva, and adult stages, suggesting that gene expression is conserved to some extent across the entire nematode life cycle. Such patterns were partly accounted for by tissue-specific genes--such as those in oocytes and the hypodermis--being expressed at different proportions. Although nematodes typically have 3-5 larval stages, the transcriptomes for these stages were found to be highly correlated within each species, suggesting high similarity among larval stages across species. For the Caenorhabditis elegans-C. briggsae and Strongyloides stercoralis-S. venezuelensis comparisons, we found that around 50% of genes were expressed at multiple stages, whereas half of their orthologues were also expressed in multiple but different stages. Such frequent changes in expression have resulted in concerted transcriptome evolution across adjacent stages, thus generating species-specific transcriptomes over the course of nematode evolution. Our study provides a first insight into the evolution of nematode transcriptomes beyond embryonic development.

evolutionary biology↗