Biology subjects

Crane, M. S.

Publications and source records attributed to Crane, M. S..

2 recordsLinked to original sources

bioRxiv2020

On a wing and a prayer: limitations and gaps in global bat wing morphology trait data

Species life history traits have a wide variety of applications in ecological and conservation research, particularly when assessing threats. The development and growth of global species trait databases are critical for improving trait-based analyses; however, it is vital to understand the gaps and biases of available data. Bats are an extremely diverse and widely distributed mammalian order, with many species facing local declines and extinction. We conducted a literature review for bat wing morphology, specifically wing loading and aspect ratio, to identify issues with data reporting and ambiguity. We collected data on field methodology, trait terminology, and data reporting and quality. We found several issues regarding semantic ambiguity in trait definitions and data reporting. Globally we found that bat wing morphology trait coverage was low. Only six bat families had over 40% trait coverage, and of those none consisted of more than 11 total species. We found similar biases in trait coverage across IUCN Redlist categories with threatened species having lower coverage. Geographically, North America, Europe, and the Indomalayan regions showed higher overall trait coverage, while both the Afrotropical and Neotropical ecoregions showed poor trait coverage. The underlying biases and gaps with bat wing morphology data have implications for researchers conducting global trait-based assessments. Implementing imputation techniques may address missing data, but only for smaller regional subsets with substantial trait coverage. However, due to the low overall trait coverage, increasing species representation in the database should be prioritized. We suggest adopting an Ecological Trait Standard vocabulary to reduce semantic ambiguity in bat wing morphology traits to improve data compilation and clarity. Additionally, we advocate that researchers adopt an Open Science approach to facilitate the growth of a bat wing morphology trait database.

ecology↗

bioRxiv2020

Lots of movement, little progress: A review of reptile home range literature

Reptiles are the most species-rich vertebrate group with a broad diversity of life history traits. Biotelemetry is an essential methodology for reptiles as it compensates for several limitations when studying their natural history. We evaluated trends in reptile spatial ecology studies focusing upon quantifying home ranges for the past twenty years. We assessed 290 English-language reptile home range studies published from 2000-2019 via a structured literature review investigating publications study location, taxonomic group, methodology, reporting, and analytical techniques. Substantial biases remain in both location and taxonomic groups in the literature, with nearly half of all studies (45%) originating from the USA. Snakes were most often studied, and crocodiles were least often studied, while testudines tended to have the greatest within study sample sizes. More than half of all studies lacked critical methodological details, limiting the number of studies for inclusion in future meta-analyses (55% of studies lacked information on individual tracking durations, and 51% lacked sufficient information on the number of times researchers recorded positions). Studies continue to rely on outdated methods to quantify space-use (including Minimum Convex Polygons and Kernel Density Estimators), often failing to report subtleties on decisions that have substantial impact on home range area estimates. Moving forward researchers can select a suite of appropriate analytical techniques tailored to their research question (dynamic Brownian Bridge Movement Models for within sample interpolation, and autocorrelated Kernel Density Estimators for beyond sample extrapolation). Only 1.4% of all evaluated studies linked to available and usable telemetry data, further hindering scientific consensus. We ultimately implore herpetologists to adopt transparent reporting practices and make liberal use of open data platforms to maximize progress in the field of reptile spatial ecology.

scientific communication and education↗