4 Works

Threshold models improve estimates of molt parameters in datasets with small sample sizes

Ryan Terrill
The timing of events in birds’ annual cycles is important to understanding life history evolution and response to global climate change. Molt timing is often measured as an index of the sum of grown feather proportion or mass within the primary flight feathers. The distribution of these molt data over time has proven difficult to model with standard linear models. The parameters of interest are at change points in model fit over time, and so...

UCE alignments and phylogenetic trees

Christopher Blair, Robert Bryson, Uri Garcia-Vazquez, Adrian Nieto-Montes De Oca, David Lazcano, John McCormack & John Klicka
Genomic data continue to advance our understanding of species limits and biogeographic patterns. However, there is still no consensus regarding appropriate methods of phylogenomic analysis that make the best use of these heterogeneous data sets. In this study, we used thousands of ultraconserved element (UCE) loci from alligator lizards in the genus Gerrhonotus to compare and contrast species trees inferred using multiple contemporary methods and provide a timeframe for biological diversification across the Mexican Transition...

Genetic data and niche differences suggest that disjunct populations of Diglossa brunneiventris are not sister lineages

Juan Luis Parra, Ana Maria Gutiérrez-Zuluaga, Catalina González-Quevedo, Jessica A. Oswald, Ryan S. Terrill & Jorge L. Pérez-Emán
Disjunct distributions within a species are of great interest in systematics and biogeography. This separation can function as a barrier to gene flow when the distance among populations exceeds the dispersal capacity of individuals, and depending on the duration of the barrier, it may eventually lead to speciation. Here we describe patterns of geographic differentiation of two disjunct populations of Diglossa brunneiventris separated by approximately 1000 km along the Andes. Diglossa brunneiventris vuilleumieri is isolated...

Cryptic diversity across the Trans-Mexican Volcanic Belt of Mexico in the montane bunchgrass lizard Sceloporus subniger (Squamata: Phrynosomatidae)

Robert Bryson, Jared Grummer, Elizabeth Connors, Joseph Tirpak, John McCormack & John Klicka
Sceloporus subniger Poglaygen & Smith is a montane bunchgrass lizard distributed across pine-oak forests of central Mexico. Prompted by the discovery of a new population of this lizard in far western Mexico, and by recent studies suggesting S. subniger may be a composite of several distinct species, we examined in more detail the genetic structure of S. subniger. We generated a mitochondrial DNA (mtDNA) dataset from 81 specimens and an ultraconserved elements (UCE) dataset representing...

Registration Year

  • 2021

Resource Types

  • Dataset


  • Occidental College
  • University of Washington
  • Universidad Autónoma de Nuevo León
  • University of Nevada Reno
  • National Autonomous University of Mexico
  • New York City College of Technology
  • University of Antioquia
  • Central University of Venezuela