Heat Waves, Global Warming &amp; Mitigation

Carlson, Ann E.

doi:10.2202/1539-8323.1099

Cited by 3 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our results indicate that, as higher ploidy individuals are selected against, a future population decline is possible if the same number of eggs and hatchlings occur at warmer temperatures (Carlson 2008). Another important consideration in light of climate change will be assessing phenological shifts in breeding (Todd et al 2010) that could produce breeding asynchrony between unisexuals and their sexual hosts.…”

Section: Effects Of Temperature and Hydroperiodmentioning

confidence: 90%

Survivorship of Ploidy-variable UnisexualAmbystomaSalamanders Across Developmental Stages

Teltser

Greenwald

2015

Herpetologica

View full text Add to dashboard Cite

Populations of unisexual Ambystoma salamanders typically consist of ploidy-variable individuals (diploid through pentaploid) that differ in their proportional representation within the populations. These salamanders reproduce using a method that has been termed kleptogenesis: stealing genetic material from males of compatible bisexual Ambystoma species (e.g., Jefferson Salamanders [A. jeffersonianum] and Blue-spotted Salamanders [A. laterale]). Kleptogenesis can result in ploidy-variable embryos within an egg mass because the unisexual female might or might not incorporate the male genome. Little is known about the survivorship of individuals having different ploidy levels. Triploid individuals are most abundant, indicating that higher ploidy individuals (tetraploids and pentaploids) are either produced more rarely, or suffer higher mortality than triploids. We assessed the frequency of ploidy levels (determined by microsatellite analysis) across four life-history stages over 2 yr: adults, early larvae, late larvae, and metamorphosed juveniles. We found that warmer breeding-season temperatures were correlated with an increased frequency of high-ploidy individuals being produced. In addition, there was a gradual decline in tetraploids across all stages as the larvae developed into adults. Breeding season temperature and selection against certain ploidy levels both appear to be important drivers of unisexual salamander population composition at our study site.

show abstract

Section: Effects Of Temperature and Hydroperiodmentioning

confidence: 90%

Survivorship of Ploidy-variable UnisexualAmbystomaSalamanders Across Developmental Stages

Teltser

Greenwald

2015

Herpetologica

View full text Add to dashboard Cite

show abstract

“…The heat-related decrease in labor capacity is expected to reach 20% in 2050 (9). In the United States, heat stress is directly related to 400 deaths/year and increases the severity of another 1,800 illnesses per year (2,6). An increase in average temperature by 2.8°C has been estimated to increase heat-related deaths by 2,000 (4).…”

mentioning

confidence: 99%

The hypophagic response to heat stress is not mediated by GPR109A or peripheral β-OH butyrate

Hepler

Foy

Higgins

et al. 2016

American Journal of Physiology-Regulatory, Integrative and Comp

View full text Add to dashboard Cite

Rising temperatures resulting from climate change will increase the incidence of heat stress, negatively impacting the labor force and food animal production. Heat stress elevates circulating β-OH butyrate, which induces vasodilation through GPR109a. Interestingly, both heat stress and intraperitoneal β-OH butyrate administration induce hypophagia. Thus, we aimed to investigate the role of β-OH butyrate in heat stress hypophagia in mice. We found that niacin, a β-OH butyrate mimetic that cannot be oxidized to generate ATP, also reduces food intake. Interestingly, the depression in food intake as a result of 8-h intraperitoneal niacin or 48-h heat exposure did not result from changes in hypothalamic expression of orexigenic or anorexigenic signals (AgRP, NPY, or POMC). Genetically eliminating GPR109a expression did not prevent the hypophagic response to heat exposure, intraperitoneal β-OH butyrate (5.7 mmol/kg), or niacin (0.8 mmol/kg). Hepatic vagotomy eliminated the hypophagic response to β-OH butyrate and niacin but did not affect the hypophagic response to heat exposure. We subsequently hypothesized that the hypophagic response to heat stress may depend on direct effects of β-OH butyrate at the central nervous system: β-OH butyrate induced hormonal changes (hyperinsulinemia, hypercorticosteronemia, and hyperleptinemia), or gene expression changes. To test these possibilities, we blocked expression of hepatic hydroxyl methyl glutaryl CoA synthase II (HMGCS2) to prevent hepatic β-OH butyrate synthesis. Mice that lack HMGCS2 maintain a hypophagic response to heat stress. Herein, we establish that the hypophagia of heat stress is independent of GPR109a, the hepatic vagus afferent nerve, and hepatic ketone body synthesis.

show abstract

Environmental Disasters: An Introduction

Farber

2011

SSRN Journal

View full text Add to dashboard Cite

Heat Waves, Global Warming & Mitigation

Cited by 3 publications

References 0 publications

Survivorship of Ploidy-variable UnisexualAmbystomaSalamanders Across Developmental Stages

Survivorship of Ploidy-variable UnisexualAmbystomaSalamanders Across Developmental Stages

The hypophagic response to heat stress is not mediated by GPR109A or peripheral β-OH butyrate

Environmental Disasters: An Introduction

Contact Info

Product

Resources

About