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Landscape-scale alterations that accompany urbanization may negatively affect the population structure of wildlife species such as freshwater turtles. Changes to nesting sites and higher mortality rates due to vehicular collisions and increased predator populations may particularly affect immature turtles and mature female turtles. We hypothesized that the proportions of adult female and immature turtles in a population will negatively correlate with landscape urbanization. As a collaborative effort of the Ecological Research as Education Network (EREN), we sampled freshwater turtle populations in 11 states across the central and eastern United States. Contrary to expectations, we found a significant positive relationship between proportions of mature female painted turtles (Chrysemys picta) and urbanization. We did not detect a relationship between urbanization and proportions of immature turtles. Urbanization may alter the thermal environment of nesting sites such that more females are produced as urbanization increases. Our approach of creating a collaborative network of scientists and students at undergraduate institutions proved valuable in terms of testing our hypothesis over a large spatial scale while also allowing students to gain hands-on experience in conservation science.

The regulatory pathways by which gut microbiota potentially shape host life histories remain largely untested, however, a constellation of research suggests that gut bacteria likely have significant effects on their hosts via metabolites. In this article we review known and hypothesized pathways by which gut microbiota influence host life histories through interfacing with the neuroendocrine system, with a focus on the insulin‐like growth factor (IGF) signalling pathway. Bacterially derived metabolites including short‐chain fatty acids (SCFAs), polyamines, and peptides likely impact host life histories as metabolic substrates, essential nutrients, and via molecular signalling with well‐studied neuroendocrine pathways. The hypothalamus–pituitary axis and insulin‐like signalling (ILS) pathways are central regulatory networks for development, growth, reproductive maturity, reproduction, and senescence and are likely targets for tests of how gut bacterial metabolites shape host life histories. SCFAs in particular, as metabolites derived from bacterial fermentation, are implicated as significant microbiome signalling molecules shown to interface with the ILS pathway as well as to bind to receptors on neuroendocrine and peripheral nervous tissues. For example, experimental increases of SCFA production have been shown to affect IGF‐1 levels in circulation and are associated with robust development, growth, reproduction, and delayed senescence. Finally, emerging ‐omics approaches are providing integrative ways to test and detail the potential diverse ways in which gut microbiota interact with their hosts and the likely important roles they play in shaping host life‐history responses to varied environmental conditions.

Disease results from interactions among the host, pathogen, and environment. Inoculation trials can quantify interactions among these players and explain aspects of disease ecology to inform management in variable and dynamic natural environments. White-nose Syndrome, a disease caused by the fungal pathogen, Pseudogymnoascus destructans (Pd), has caused severe population declines of several bat species in North America. We conducted the first experimental infection trial on the tri-colored bat, Perimyotis subflavus, to test the effect of temperature and humidity on disease severity. We also tested the effects of temperature and humidity on fungal growth and persistence on substrates. Unexpectedly, only 37% (35/95) of bats experimentally inoculated with Pd at the start of the experiment showed any infection response or disease symptoms after 83 days of captive hibernation. There was no evidence that temperature or humidity influenced infection response. Temperature had a strong effect on fungal growth on media plates, but the influence of humidity was more variable and uncertain. Designing laboratory studies to maximize research outcomes would be beneficial given the high costs of such efforts and potential for unexpected outcomes. Understanding the influence of microclimates on host–pathogen interactions remains an important consideration for managing wildlife diseases, particularly in variable environments.