It is predicted that climate change will cause species extinctions and distributional shifts in coming decades, but data to validate these predictions are relatively scarce Here, we compare recent and historical surveys for 48 Mexican lizard species at 200 sites Since 1975, 12% of local populations have gone extinct We verified physiological models of extinction risk with observed local extinctions and extended projections worldwide Since 1975, we estimate that 4% of local populations have gone extinct worldwide, but by 2080 local extinctions are projected to reach 39% worldwide, and species extinctions may reach 20% Global extinction projections were validated with local extinctions observed from 1975 to 2009 for regional biotas on four other continents, suggesting that lizards have already crossed a threshold for extinctions caused by climate change

http://max2.ese.u-psud.fr/epc/conservation/PDFs/HIPE/Sinervo2010.pdf

Erosion of lizard diversity by climate change and altered thermal niches.

https://recipp.ipp.pt/bitstream/10400.22/3012/4/ART_LuciaSantos_2010_GRAQ.pdf

Ecotoxicological aspects related to the presence of pharmaceuticals in the aquatic environment

A recently developed integrative framework proposes that the vulnerability of a species to environmental change depends on the species' exposure and sensitivity to environmental change, its resilience to perturbations and its potential to adapt to change. These vulnerability criteria require behavioural, physiological and genetic data. With this information in hand, biologists can predict organisms most at risk from environmental change. Biologists and managers can then target organisms and habitats most at risk. Unfortunately, the required data (e.g. optimal physiological temperatures) are rarely available. Here, we evaluate the reliability of potential proxies (e.g. critical temperatures) that are often available for some groups. Several proxies for ectotherms are promising, but analogous ones for endotherms are lacking. We also develop a simple graphical model of how behavioural thermoregulation, acclimation and adaptation may interact to influence vulnerability over time. After considering this model together with the proxies available for physiological sensitivity to climate change, we conclude that ectotherms sharing vulnerability traits seem concentrated in lowland tropical forests. Their vulnerability may be exacerbated by negative biotic interactions. Whether tropical forest (or other) species can adapt to warming environments is unclear, as genetic and selective data are scant. Nevertheless, the prospects for tropical forest ectotherms appear grim.

https://royalsocietypublishing.org/doi/pdf/10.1098/rstb.2012.0005

Predicting organismal vulnerability to climate warming: roles of behaviour, physiology and adaptation

Human pharmaceuticals in the aquatic environment: a challenge to Green Chemistry.

A review of personal care products in the aquatic environment: environmental concentrations and toxicity.

Use of operative temperature and standard operative temperature models in thermal biology

Although pharmaceuticals are increasingly found in surface waters, environmental levels of many of these compounds are not acutely toxic to model test organisms. Prior to conducting appropriate ecological risk assessments of pharmaceuticals, the mode of action-based biomarkers needs to be developed for non-target species. To evaluate toxicity of the β-adrenergic blockers propranolol and metoprolol on non-target biota, we assessed standard ecotoxicological endpoints after 9 days of subchronic exposure in a transgenerational study with Daphnia magna. On day 9 of exposure, the lowest observed effects concentration (LOEC) for growth were 0.44 mg L−1 for propranolol and 12 mg L−1 for metoprolol. Total fecundity LOECs for the 9-day exposure were 0.11 mg L−1 and 6 mg L−1 for propranolol and metoprolol, respectively. In addition to typical ecotoxicological endpoints, we evaluated the utility of employing the physiological biomarkers of heart rate and metabolic rate following subchronic and acute exposures to propranolol and metoprolol. Propranolol and metoprolol LOECs for heart rate were 0.055 mg L−1 and 3.1 mg L−1, significantly lower than the LOECs for growth and reproduction. At these concentrations, heart rate was significantly lower than the control values for both compounds. Daphnia magna endpoint sensitivity to chronic propranolol and metoprolol exposure was mortality < growth < fecundity < heart rate. Second generation D. magna were less sensitive to both compounds. Responses of the physiological biomarkers heart rate and metabolic activity suggest that propranolol and metoprolol exerts sublethal toxicity to D. magna at lower concentrations than observed in the classical endpoints.

Physiological and Reproductive Effects of Beta Adrenergic Receptor Antagonists in Daphnia magna

b ¨¨ ¨ Abstract Chicken embryos were chronically exposed to hypoxia ( ;110 mmHg) during development, and assessed for PO2

Chronic hypoxia alters the physiological and morphological trajectories of developing chicken embryos.

Parental investment in eggs and, consequently, in offspring can profoundly influence the phenotype, survival and ultimately evolutionary fitness of an organism. Avian eggs are excellent model systems to examine maternal allocation of energy translated through egg size variation. We used the natural range in emu Dromaius novaehollandiae egg size, from 400 g to >700 g, to examine the influence of maternal investment in eggs on the morphology and physiology of hatchlings. Female emus provisioned larger eggs with a greater absolute amount of energy, nutrients and water in the yolk and albumen. Variation in maternal investment was reflected in differences in hatchling size, which increased isometrically with egg size. Egg size also influenced the physiology of developing emu embryos, such that late-term embryonic metabolic rate was positively correlated with egg size and embryos developing in larger eggs consumed more yolk during development. Large eggs produced hatchlings that were both heavier (yolk-free wet and dry mass) and structurally larger (tibiotarsus and culmen lengths) than hatchlings emerging from smaller eggs. As with many other precocial birds, larger hatchlings also contained more water, which was reflected in a greater blood volume. However, blood osmolality, hemoglobin content and hematocrit did not vary with hatchling mass. Emu maternal investment in offspring, measured by egg size and composition, is significantly correlated with the morphology and physiology of hatchlings and, in turn, may influence the success of these organisms during the first days of the juvenile stage.

/pdf/maternal-effects-of-egg-size-on-emu-dromaius-novaehollandiae-3yaxzoy75p.pdf

Maternal effects of egg size on emu Dromaius novaehollandiae egg composition and hatchling phenotype.

We examined the acute effects of triclosan (TCS) exposure, a common antimicrobial found as a contaminant in the field, on survival and physiology of amphibian larvae. LC50 values were determined after 96 h for North American larval species: Acris crepitans blanchardii , Bufo woodhousii woodhousii , Rana sphenocephala , and for a developmental model: Xenopus laevis . Amphibian larvae were most sensitive to TCS exposure during early development based upon 96-h LC50 values. Heart rates for X. laevis and North American larvae exposed to TCS were variable throughout development. Metabolic rates of X. laevis and R. sphenocephala larvae exposed to TCS were significantly affected in larvae exposed to [50% LC50] and [LC50]. Tissue uptake and tissue bioconcentration factor (BCF) of TCS were investigated in X. laevis , B. woodhousii woodhousii , and R. sphenocephala . In general, a significant increase was observed as exposure concentration increased. Tissue BCF values were dependent upon stage and species. While TCS concentrations used here are higher than environmental concentrations, exposure to TCS was dependent upon species and developmental stage, with early developmental stages being most sensitive to TCS exposure.

Edward M. Dzialowski

Papers

Use of operative temperature and standard operative temperature models in thermal biology

Physiological and Reproductive Effects of Beta Adrenergic Receptor Antagonists in Daphnia magna

Chronic hypoxia alters the physiological and morphological trajectories of developing chicken embryos.

Maternal effects of egg size on emu Dromaius novaehollandiae egg composition and hatchling phenotype.

Physiological effects and bioconcentration of triclosan on amphibian larvae.