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Lin Kang

Publications and source records attributed to Lin Kang.

3 recordsLinked to original sources

DNA metabarcoding-based evaluation of the diet of Big Brown Bats (Eptesicus fuscus) in the Mid-Atlantic region

High-throughput DNA sequencing can generate large genetic datasets in a cost-effective manner. Although the diet of Eptesicus fuscus (Big Brown Bat) has been studied widely in natural and rural systems using visual identification of prey items in feces, our aim was to more completely assess diet using a metabarcoding approach across a wide urban–natural landscape gradient in the mid-Atlantic region. Concordant with our expectations and previous Big Brown Bat diet studies from visual identification, we observed a high abundance of Coleoptera (beetles) relative to other insect orders. Although a possible improvement over visual techniques for studying food habits, we suggest caution in interpreting metabarcoding results in diet studies. We noted observations of environmental or contaminant taxa within these data, and designed a stringent filtering method that we used to eliminate these taxa, but that also removed previously documented prey taxa from our dataset.

Maryland, Pennsylvania, Virginia, West Virginia

Analysis of genomic sequence data reveals the origin and evolutionary separation of Hawaiian hoary bat populations

We examine the genetic history and population status of Hawaiian hoary bats ( Lasiurus semotus ), the most isolated bats on Earth, and their relationship to northern hoary bats ( Lasiurus cinereus ), through whole-genome analysis of single-nucleotide polymorphisms mapped to a de novo-assembled reference genome. Profiles of genomic diversity and divergence indicate that Hawaiian hoary bats are distinct from northern hoary bats, and form a monophyletic group, indicating a single ancestral colonization event 1.34 Ma, followed by substantial divergence between islands beginning 0.51 Ma. Phylogenetic analysis indicates Maui is central to the radiation across the archipelago, with the southward expansion to Hawai‘i and westward to O‘ahu and Kaua‘i. Because this endangered species is of conservation concern, a clearer understanding of the population genetic structure of this bat in the Hawaiian Islands is of timely importance.

Hawaii

Transcriptomic imprints of adaptation to fresh water: parallel evolution of osmoregulatory gene expression in the Alewife

Comparative approaches in physiological genomics offer an opportunity to understand the functional importance of genes involved in niche exploitation. We used populations of Alewife ( Alosa pseudoharengus ) to explore the transcriptional mechanisms that underlie adaptation to fresh water. Ancestrally anadromous Alewives have recently formed multiple, independently derived, landlocked populations, which exhibit reduced tolerance of saltwater and enhanced tolerance of fresh water. Using RNA-seq, we compared transcriptional responses of an anadromous Alewife population to two landlocked populations after acclimation to fresh (0 ppt) and saltwater (35 ppt). Our results suggest that the gill transcriptome has evolved in primarily discordant ways between independent landlocked populations and their anadromous ancestor. By contrast, evolved shifts in the transcription of a small suite of well-characterized osmoregulatory genes exhibited a strong degree of parallelism. In particular, transcription of genes that regulate gill ion exchange has diverged in accordance with functional predictions: freshwater ion-uptake genes (most notably, the ‘freshwater paralog’ of Na + /K + -ATPase α-subunit) were more highly expressed in landlocked forms, whereas genes that regulate saltwater ion secretion (e.g. the ‘saltwater paralog’ of NKAα) exhibited a blunted response to saltwater. Parallel divergence of ion transport gene expression is associated with shifts in salinity tolerance limits among landlocked forms, suggesting that changes to the gill's transcriptional response to salinity facilitate freshwater adaptation.

Molecular Ecology