Low temperatures impact species distributions of jumping spiders across a desert elevational cline

Abstract

Temperature is known to influence many aspects of organisms and is frequently linked to geographical species distributions. Despite the importance of a broad understanding of an animal's thermal biology, few studies incorporate more than one metric of thermal biology. Here we examined an elevational assemblage of Habronattus jumping spiders to measure different aspects of their thermal biology including thermal limits (CT min , CT max), thermal preference, VĊO 2 as proxy for metabolic rate, locomotor behavior and warming tolerance. We used these data to test whether thermal biology helped explain how species were distributed across elevation. Habronattus had high CT max values, which did not differ among species across the elevational gradient. The highest-elevation species had a lower CT min than any other species. All species had a strong thermal preference around 37°C. With respect to performance, one of the middle elevation species was significantly less temperature-sensitive in metabolic rate. Differences between species with respect to locomotion (jump distance) were likely driven by differences in mass, with no differences in thermal performance across elevation. We suggest that Habronattus distributions follow Brett's rule, a rule that predicts more geographical variation in cold tolerance than heat. Additionally, we suggest that physiological tolerances interact with biotic factors, particularly those related to courtship and mate choice to influence species distributions. Habronattus also had very high warming tolerance values (> 20°C, on average). Taken together, these data suggest that Habronattus are resilient in the face of climate-change related shifts in temperature.

Snow modulates winter energy use and cold exposure across an elevation gradient in a montane ectotherm

“…Our physiological measurements came from a single population, and it is possible that either cold tolerance or energetic traits differed among populations due to local adaptation or neutral processes (Brandt et al, 2020; Lester & Irwin, 2012; Sinclair et al, 2012). More research is needed to understand how clinal variation in cold tolerance or energetics interacts with exposure to drive sensitivity of a range of species to climate change.…”

The Bogert effect, a factor in evolution

“…These studies fit into a broader picture of physiological variation in ectotherms. In general, upper physiological limits exhibit less geographic divergence, particularly in terrestrial organisms (e.g., Gaston and Chown 1999;Sunday et al 2011;Brandt et al 2020), a biogeographic pattern known as Brett's rule (Brett 1956;Gaston et al 2009). Likewise, other studies have found higher phylogenetic signal in upper physiological limits than in lower limits (Grigg and Buckley 2013;Hoffmann et al 2013;Gutiérrez-Pesquera et al 2016 signal (by itself) should be interpreted with caution.…”

Photodynamic Therapy Using 5-Aminolevulinic Acid (Ala) for the Treatment of Chronic Periodontitis: A Prospective Case Series

“…The aminolaevulinic acid is the precursor of protoporphyrin IX (PpIX), it is normally synthesized in mitochondria, thanks to the condensation reaction between glycine and succinyl-CoA [72], but it can also be administrated exogenously as a prodrug [51]. The ALA molecules are better absorbed intracellularly than the PpIX, and their accumulation and photoactivation in porphyrins (PAPs) is higher in cells with greater metabolic activity, such as tumor cells, bacteria, and inflammatory cells [73]. ALADENT device allows, therefore, to maximize the penetration of the PS in the bacterial membrane.…”