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Bai X, Wang XJ, Ma CS, Ma G. Heat-avoidance behavior associates with thermal sensitivity rather than tolerance in aphid assemblages. J Therm Biol 2023; 114:103550. [PMID: 37344023 DOI: 10.1016/j.jtherbio.2023.103550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 03/20/2023] [Accepted: 03/21/2023] [Indexed: 06/23/2023]
Abstract
How to predict animals' heat-avoidance behaviors is critical since behavior stands the first line for animals dealing with frequent heat events under ongoing climate warming. However, the discrepancy between the scarcity of research on heat-avoidance behaviors and the commonness of eco-physiological data for thermal tolerance and for thermal sensitivity such as the temperature-dependent survival time makes it difficult to link physiological thermal traits to heat-avoidance behavior. Aphids usually suck plant sap on a fixed site on the host plants at moderate temperatures, but they will leave and seek cooler feeding sites under stressful temperatures. Here we take the cereal aphid assemblages comprising different species with various development stages as a model system. We tested the hypotheses that heat tolerance (critical thermal maximum, CTmax) or heat sensitivity (temperature-dependent declining rate of survival time, similarly hereinafter) would associate with the temperature at which aphid activate heat-avoidance behavior. Specifically, we hypothesized the aphids with less heat tolerance or greater heat sensitivity would take a lower heat risk by leaving the host plant earlier. By mimicking the linear increase in ambient temperature during the daytime, we measured the CTmax and the heat-avoidance temperature (HAT, at which aphids leave the host plant to find cooler places) to understand their heat tolerance and heat-avoidance behavior. Then, we tested the survival time of aphids at different temperatures and calculated the slope of survival time declining with temperature to assess their heat sensitivity (HS). Finally, we examined the relationships between CTmax and HAT and between HS and HAT to understand if the heat-avoidance behavior associates with heat tolerance or with heat sensitivity. The results showed that HS and HAT had a strong correlation, with more heat sensitive individuals displayed lower HAT. By contrast, CTmax and HAT had a weak correlation. Our results thus provide evidence that heat sensitivity is a more reliable indicator than thermal tolerance linking with the heat-avoidance behavior in the aphid assemblages. Most existing studies use the indexes related to thermal tolerance to predict warming impacts. Our findings highlight the urgency to incorporate thermal sensitivity when predicting animal responses to climate change.
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Affiliation(s)
- Xue Bai
- Climate Change Biology Research Group, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Xue-Jing Wang
- Climate Change Biology Research Group, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China; School of Life Science, Institute of Life Science and Green Development, Hebei University, Baoding, 071002, China
| | - Chun-Sen Ma
- Climate Change Biology Research Group, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China; School of Life Science, Institute of Life Science and Green Development, Hebei University, Baoding, 071002, China.
| | - Gang Ma
- Climate Change Biology Research Group, State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
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Meehan ML, Lindo Z. Mismatches in thermal performance between ectothermic predators and prey alter interaction strength and top-down control. Oecologia 2023; 201:1005-1015. [PMID: 37039893 DOI: 10.1007/s00442-023-05372-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 04/04/2023] [Indexed: 04/12/2023]
Abstract
Climate change can alter predator-prey interactions when predators and prey have different thermal preferences as temperature change can exacerbate thermal mismatches (also called thermal asymmetry) with population-level consequences. We tested this using micro-arthropod predators (Stratiolaelaps scimitus) and prey (Folsomia candida) that differ in their temperature optima to examine predator-prey interactions across two temperature ranges, a cool (12 and 20 °C) and warm (20 and 26 °C) range. We predict that the lower thermal preference and optimum in F. candida will alter top-down control (i.e., interaction strength) by predators with interaction strength being strongest at intermediate temperatures, coinciding with F. candida thermal optimum. Predators and prey were placed in mesocosms, whereafter we measured population (predator and prey abundance), trait-based (average predator and prey body mass, and prey body length distribution), and predator-prey indices (predator-prey mass ratio (PPMR), Dynamic Index, and Log Response Ratio) to determine how temperature affected their interactions. Prey populations were the highest at intermediate temperatures (average temperature exposure: 16-23 °C) but declined at warmer temperatures (average temperature exposure: 24.5-26 °C). Predators consistently lowered prey abundances and average prey mass increased when predators were added. Top-down control was the greatest at intermediate temperatures (indicated by Log Response Ratio) when temperatures were near or below the thermal optimum for both species. Temperature-related prey declines negated top-down control under the warmest conditions suggesting that mismatches in thermal performance between predators and their prey will alter the strength and dominance of top-down or bottom-up forces of predator-prey interactions in a warmer world.
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Affiliation(s)
- Matthew L Meehan
- Department of Biology, Western University, London, ON, N6A 3K7, Canada.
- Department of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9BL, UK.
| | - Zoë Lindo
- Department of Biology, Western University, London, ON, N6A 3K7, Canada
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Meehan ML, Turnbull KF, Sinclair BJ, Lindo Z. Predators minimize energy costs, rather than maximize energy gains under warming: Evidence from a microcosm feeding experiment. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14131] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Matthew L. Meehan
- Department of Biology Western University 1151 Richmond Street, N6A 3K7 London Ontario Canada
| | - Kurtis F. Turnbull
- Department of Biology Western University 1151 Richmond Street, N6A 3K7 London Ontario Canada
| | - Brent J. Sinclair
- Department of Biology Western University 1151 Richmond Street, N6A 3K7 London Ontario Canada
| | - Zoë Lindo
- Department of Biology Western University 1151 Richmond Street, N6A 3K7 London Ontario Canada
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