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- Creator:
- Crowell, Hayley L . , Curlis, John David, Weller, Hannah I., and Davis Rabosky, Alison R.
- Description:
- Ultraviolet (UV) wavelengths invisible to humans are primarily studied in the context of reproduction and social signaling. This narrow focus can arise from bias in taxa studied, which are often brightly colored in human-visible wavelengths. Our research describes undocumented UV color patterns across 110 diverse species of Western Hemisphere snakes and tests the hypothesized roles of reproduction versus predator avoidance in the evolution of UV coloration. Phylogenetically-informed tests of life stage, sex, and habitat showed unexpected support for the predator defense hypothesis, with pronounced differences in snake conspicuousness explained by UV coloration. UV reflectance was not predictable from any aspect of visible color pattern, suggesting high potential for transformative discoveries in other “cryptically-colored” lineages across the tree of life.
- Keyword:
- color, ecology, evolution, predators, snakes, and ultraviolet
- Citation to related publication:
- Crowell, H.L, Curlis, J.D., Weller, H.I, & Davis Rabosky, A. R. (2023). Predators drive the evolution of ultraviolet coloration in snakes. in press.
- Discipline:
- Science
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- Creator:
- Fuller, Jennifer, Rowan, Erin, Landgraf, Ava, Alofs, Karen, Foufopoulos, Johannes, and Gronewold, Andrew
- Description:
- This study investigates the rapid decline of black tern (Chlidonias niger) over eight years in one of Michigan’s largest colonies, Lake St. Clair. 1. Nesting Success Model: A multiple logistic regression with a binomial (logit-link) fit using the glm() function from the ‘stats’ package in R (55) to determine the influence of habitat and biological predictors on nesting survival. 2. ArcMap visualization of Nesting Success: To visualize the geographic extent of the habitat’s potential to predispose nests’ vulnerability, the coefficients and intercept from our selected GLM were applied to raster layers in ArcMap using the Raster Calculator Tool. 3. Population Change & Habitat Extent: To quantify sub-colony breeding pair population size and their response to changes in sub-colony habitat in the geospatial model, we applied a general linear mixed model (GLMM) using the lmer() function from the ‘lme4’ package in R (55). Predictor variables were chosen a priori, and included the area of open water, uninhabitable vegetation (NDVI>0.72), any habitable area, and area with >50% hatch success.
- Keyword:
- black terns, wetlands, ecology, climate change, lake levels, Great Lakes, waterbirds, ornithology, general linear model, geospatial, GIS, nesting success, avian, and breeding
- Citation to related publication:
- Fuller, J., Rowan, E., Landgraf, A., Alofs, K., Foufopoulos, J., Gronewold, A., (2021). Collapse of a Black Tern Colony (Chlidonias niger) as a Result of Climate Change Driven Lake-Level Extremes and Anthropogenic Habitat Alteration [Data set]. University of Michigan - Deep Blue. and Fuller, J., et al. (2021). Shorebird colony collapses under climate driven lake-level rise and anthropogenic stressors. Forthcoming.
- Discipline:
- Science
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- Creator:
- Walsh, Lisa L
- Description:
- Stable isotope values of carbon (δ13C) and nitrogen (δ15N) from Virginia opossum (Didelphis virginiana) guard hairs were analyzed to evaluate the ecology and winter adaptations in opossums by Dr. Lisa L. Walsh as part of her Ph.D. thesis in the Ecology and Evolutionary Biology Department. The collection of stable isotope data took place from 2017 to 2019. Guard hair was processed at the University of Michigan and analyzed by the University of New Mexico Center for Stable Isotopes (UNM-CSI, USA). Captive and wild opossums were evaluated for evidence of biannual or incomplete biannual molting, a mammalian adaptation to harsh winters. Results suggest opossums do not exhibit either winter molting strategy and that guard hairs capture the opossum’s lifetime diet (Walsh and Tucker 2021). The stable isotope values were used to test the hypothesis that a Type A generalist’s niche is positively correlated with habitat heterogeneity and to evaluate which climate variables best explained isotope values. There was a positive correlation between isotopic niche size and habitat-diversity indexes (Walsh and Tucker 2020). The δ13C values from opossums in the Midwest and Northeast to test whether opossums rely on anthropogenic trash to survive extreme winters. There was no significant relationship between δ13C and winter variables, but there was a significant increase in variance of Midwest opossums’ δ13C after the 1970 corn agricultural boom (Walsh and Tucker 2023).
- Keyword:
- stable isotope, Virginia opossum, mesopredator, ecology, and mammal
- Citation to related publication:
- Walsh, L.L. and P.K. Tucker. 2020. Habitat heterogeneity is correlated with isotopic niche breadth across the range of a mammalian generalist mesopredator. Ecosphere, 11(12): e03314. https://doi.org/10.1002/ecs2.3314, Walsh, L.L. and P.K. Tucker. 2021. Stable isotope values suggest opossums (Didelphis virginiana) at their northern edge do not seasonally molt. Northeastern Naturalist, 28(1): 1-8. https://doi.org/10.1656/045.028.0101, and Walsh, L.L., and P.K. Tucker. 2023. Evaluating anthropogenic influence on a mesopredator: Opossum (Didelphis virginiana) isotope values influenced by corn agriculture more than urbanization. Canadian Journal of Zoology, 101: https://doi.org/10.1139/cjz-2021-0172.
- Discipline:
- Science
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- Creator:
- Umaña, María Natalia, Zambrano, Jenny, Weemstra, Monique, and Allen, Dave
- Description:
- The objective of this research was to improve our understanding of tree growth from underlying variation in leaf and root functional traits. This knowledge ultimately enhances our knowledge of the above- and belowground processes that are involved in structuring forest communities. To this end, we determine which, how and to what degree (combinations of) leaf and root traits influence growth rates across ten temperate tree species along a soil carbon (C) and N gradient growing at the Big Woods plot at the E.S. George Reserve, Pickney, MI. This plot is part of the Smithsonian Institution's Forest Global Earth Observatory (ForestGEO) global network of forest research sites. https://forestgeo.si.edu/ and This dataset contains data on the leaf and root traits of several individuals from tree species, as well as on the soil properties at the Big Woods plots at the E.S. George Reserve, Pickney, MI. Data were collected in June 2019, and used to explain and predict the growth rates of the trees at Big Woods. [Growth data were obtained from Allen et al., 2019, https://doi.org/10.7302/wx55-kt18]. Each file contains data on leaf traits, root traits, and soil properties. Trait data are presented per individual tree for each of the 10 study species. Soil data are represented per soil sample, with four soil samples collected per subplot throughout the Big Woods plot (see legend, and publication for explanation). Descriptions and units per variable/column are provided in the legend tab in each file.
- Keyword:
- ecology, forests, Michigan, ForestGEO, Big Woods, Roots, Leaves, Tree growth, and Forest soils
- Citation to related publication:
- M. Weemstra, J. Zambrano, D. Allen, MN Umaña. (In press) Tree growth increases through opposing above- and belowground resource strategies. Journal of Ecology. https://doi.org/10.1111/1365-2745.13729
- Discipline:
- Science