Category: New Lit Abstracts Page 4 of 5

Aspects of global change create stressful thermal environments that threaten biodiversity. Oviparous, non‐avian reptiles have received considerable attention because eggs are left to develop under prevailing conditions, leaving developing embryos vulnerable to increases in temperature. Though many studies assess embryo responses to long‐term (i.e., chronic), constant incubation temperatures, few assess responses to acute exposures which are more relevant for many species. We subjected brown anole (Anolis sagrei) eggs to heat shocks, thermal ramps, and extreme diurnal fluctuations to determine the lethal temperature of embryos, measure the thermal sensitivity of embryo heart rate and metabolism, and quantify the effects of sublethal but stressful temperatures on development and hatchling phenotypes and survival. Most embryos died at heat shocks of 45°C or 46°C, which is ~12°C warmer than the highest constant temperatures suitable for successful development. Heart rate and O₂ consumption increased with temperature; however, as embryos approached the lethal temperature, heart rate and CO₂ production continued rising while O₂ consumption plateaued. These data indicate a mismatch between oxygen supply and demand at high temperatures. Exposure to extreme, diurnal fluctuations depressed embryo developmental rates and heart rates, and resulted in hatchlings with smaller body size, reduced growth rates, and lower survival in the laboratory. Thus, even brief exposure to extreme temperatures can have important effects on embryo development, and our study highlights the role of both immediate and cumulative effects of high temperatures on egg survival. Such effects must be considered to predict how populations will respond to global change.

1. Invasive species are a world‐wide threat to biodiversity. Yet, our understanding of biological invasions remains incomplete, partly due to the difficulty of tracking and studying behavioural interactions in recently created species interactions.
2. We tested whether the interactions between the recently introduced invasive lizard Anolis cristatellus and the native Anolis oculatus in Dominica have led to changes in species recognition and aggressive behaviour of the native species.
3. The use of realistic robots allowed us to test the behavioural response of 131 A. oculatus males towards relevant and controlled conspecific versus heterospecific stimuli, directly in the field and in two contexts (allopatry vs. sympatry).
4. Our results show that species recognition evolved prior to sympatry in A. oculatus. Moreover, interspecific competition resulted in an increase in the time spent displaying and a divergence in the aggressive behaviour of the native species towards conspecifics versus heterospecifics. Inherent species recognition and higher aggressive behaviour may limit species coexistence as they are expected to favour A. oculatus during territorial interactions with A. cristatellus.
5. While more studies are needed to understand the causes of these behavioural shifts and their consequences on long‐term species coexistence, the present study highlights the role of behaviour as a first response to interspecific interactions.

Here, we investigated the prevalence of Salmonellaenterica, with and without resistance to 17 common antimicrobial agents, in 706 green anoles (Anolis carolinensis) that were collected in Naha and Tomishiro Cities, Okinawa Main Island, Japan, between 2009 and 2014. Salmonella strains, including S. enterica Weltevreden and Enteritidis serovars, were identified in the large intestinal content samples extracted from 15 (2.1%) of the analyzed green anoles. No antimicrobial resistance was detected. Thus, the present study demonstrates that although the prevalence of Salmonella and the risk of its transmission from the green anoles to humans or other animals on Okinawa Main Island are relatively low, the green anole population nevertheless represents a potential source of Salmonella infection that could affect human health in this region.