7 Works

Near-shore island lizard fauna shaped by a combination of human-mediated and natural dispersal

Jeanne Robertson, Patricia Salerno, Lauren Chan, W. Chris Funk & Gregory Pauly
Aim: Island biotas provide opportunities to study colonization and adaptation to novel environments. Islands, especially near-shore islands, may have a long record of human habitation such that some lineages result from human-assisted introductions. Here, we combine phylogenetic analyses with fossil data and historical specimen records to reconstruct colonization histories, characterize among-island divergence, and assess the role of humans in shaping the evolutionary history of lizards inhabiting a near-shore island archipelago. Location: Channel Islands and adjacent...

New giant carnivorous dinosaur reveals convergent evolutionary trends in theropod arm reduction

Juan Canale, Sebastian Apesteguia, Pablo Gallina, Jonathan Mitchell, Nathan Smith, Thomas Cullen, Akiko Shinya, Federico Gianechini & Peter Makovicky
Giant carnivorous dinosaurs such as Tyrannosaurus rex and abelisaurids are characterized by highly reduced forelimbs that stand in contrast to their huge dimensions, massive skulls, and obligate bipedalism.​ Another group that follows this pattern, yet is still poorly known, is the Carcharodontosauridae: dominant predators that inhabited most continents during the Early Cretaceous​​ and reached their largest sizes in Aptian-Cenomanian times.​ Despite many discoveries over the last three decades, aspects of their anatomy, especially with regard...

A manager’s guide to using eDNA metabarcoding in marine ecosystems

Zachary Gold, Adam R. Wall, Teia M. Schweizer, N. Dean Pentcheff, Emily E. Curd, Paul H. Barber, Rachel S. Meyer, Robert Wayne, Kevin Stolzenbach, Kat Prickett, Justin Luedy & Regina Wetzer
Environmental DNA (eDNA) metabarcoding is a powerful tool that can enhance marine ecosystem/biodiversity monitoring programs. Here we outline five important steps managers and researchers should consider when developing eDNA monitoring program: 1) select genes and primers to target focal taxa; 2) assemble or develop comprehensive barcode reference databases; 3) apply rigorous site occupancy based decontamination pipelines; 4) conduct pilot studies to define spatial and temporal variance of eDNA; and 5) archive samples, extracts, and raw...

Cricetodontine character state matrix

Robert Martin, Thomas Kelly & Patricia Holroyd
In this study we appraised the dental morphology and potential origin of two Neogene cricetodontine-like muroids, Pliotomodon primitivus from sediments in northern California and an undescribed muroid from central Oregon. Dental features of Pliotomodon are similar to those of Eurasian genera such as Byzantinia, Hispanomys and Ruscinomys, but the unusual morphology of M3/m3, with continuous enamel connections across their lingual surfaces closing the hypoflexus and posteroflexid, respectively, plus retention of only three roots on M1,...

Genetic structure and historic demography of endangered unarmored threespine stickleback at southern latitudes signals a need for new management directives

Rachel Turba, Jonathan Richmond, Sorel Fitz-Gibbon, Marco Morselli, Robert Fisher, Camm Swift, Gorgonio Ruiz-Campos, Adam Backlin & David Jacobs
Habitat loss, flood control infrastructure, and drought have left most of southern California and northern Baja California’s native freshwater fish fauna on the brink of extinction, including the endangered unarmored threespine stickleback (Gasterosteus aculeatus williamsoni). This subspecies, an unusual morph lacking the typical lateral bony plates of the G. aculeatus complex, occurs at arid southern latitudes in the eastern Pacific Ocean and survives in only three inland locations. Managers have been stymied by a lack...

Data: Applying stochastic and Bayesian integral projection modeling to amphibian population viability analysis

Arianne Messerman, Adam Clause, Levi Gray, Martin Krkošek, Hilary Rollins, Peter Trenham, Bradley Shaffer & Christopher Searcy
Integral projection models (IPMs) can estimate the population dynamics of species for which both discrete life stages and continuous variables influence demographic rates. Stochastic IPMs for imperiled species, in turn, can facilitate population viability analyses (PVAs) to guide conservation decision-making. Biphasic amphibians are globally distributed, often highly imperiled, and ecologically well-suited to the IPM approach. Herein, we present the first stochastic size- and stage-structured IPM for a biphasic amphibian, the U.S. federally threatened California tiger...

Conservation genetics of an island-endemic lizard: low Ne and the critical role of intermediate temperatures for genetic connectivity

Daryl Trumbo, W. Chris Funk, Gregory Pauly & Jeanne Robertson
Island populations are at higher risk of extinction than mainland populations. Therefore, understanding the factors that facilitate connectivity is particularly pressing for the conservation of island taxa. Sceloporus occidentalis becki, the Island Fence Lizard, is an endemic taxon restricted to the Northern Channel Islands, part of a nearshore archipelago in Southern California, USA. Since the Last Glacial Maximum, fence lizard habitat on the Northern Channel Islands has decreased with rising sea levels and increasing temperatures...

Registration Year

  • 2022

Resource Types

  • Dataset


  • Natural History Museum of Los Angeles County
  • Colorado State University
  • University of California Los Angeles
  • California State University, Northridge
  • National University of San Luis
  • Field Museum of Natural History
  • Universidad Autónoma de Baja California Sur
  • University of Minnesota
  • Murray State University
  • Universidad Maimónides