C. C. Witt

Extraordinary levels of per- and polyfluoroalkyl substances (PFAS) in vertebrate animals at a New Mexico desert oasis: multiple pathways for wildlife and human exposure

This study measures high levels of PFAS in vertebrates at a New Mexico desert oasis, showing contamination across multiple trophic levels and exposure pathways.

Hummingbird blood traits track oxygen availability across space and time

The paper examines blood traits in Andean hummingbirds across elevation gradients, finding that elevation effects on hemoglobin and hematocrit are consistent across species and individuals, but mechanisms of adjustment vary with elevation.

Blood variation implicates respiratory limits on elevational ranges of Andean birds

This study examines how hematological traits influence elevational ranges of Andean birds, finding that plasticity and reduced local variation near range limits are linked to oxygen availability constraints.

Comparing divergence landscapes from reduced-representation and whole-genome re-sequencing in the yellow-rumped warbler (Setophaga coronata) species complex

This study compares divergence landscapes from reduced-representation and whole-genome re-sequencing in yellow-rumped warblers, finding WGS better detects fine-scale divergence features.

Detecting turnover among complex communities using null models: A case study with sky-island haemosporidian parasites

The paper develops null models to detect turnover in avian haemosporidian parasite communities across sky islands, finding significant differences among adjacent mountain ranges.

Phylogeny, transposable element and sex chromosome evolution of the basal lineage of birds

This study investigates sex chromosome evolution in paleognath birds, finding that tinamous have higher substitution rates and unique evolutionary strata without chromosomal inversion.

The role of mutation bias in adaptive molecular evolution: insights from convergent changes in protein function

The paper examines how mutation bias at CpG dinucleotides influences adaptive molecular evolution by analyzing convergent changes in hemoglobin function across high-altitude birds.

Deeply conserved susceptibility in a multi-host, multi-parasite system

The paper investigates susceptibility to haemosporidian parasites across bird species, finding that host phylogeny significantly influences infection rates.

Ecology, Not Distance, Explains Community Composition in Parasites of Sky-Island Audubon’s Warblers

This study shows that parasite community composition in Audubon’s Warblers is better explained by ecological factors and bird community composition than by geographic distance.

Why are tropical mountain passes ‘low’ for some species? Genetic and stable-isotope tests for differentiation, migration, and expansion in elevational generalist songbirds

This paper investigates elevational generalism in tropical songbirds, finding genetic divergence, seasonal movements, and recent expansions in three out of four species.

An extinct hummingbird species that never was: a cautionary tale about sampling issues in molecular phylogenetics

The paper reanalyzes mitochondrial DNA data to challenge the status of Heliangelus zusii as a distinct species, suggesting it may result from hybridization with Aglaiocercus kingii.