Analyses of heat tolerance in insects often suggest that this trait is relatively invariant, leading to the use of fixed thermal maxima in models predicting future distribution of species in a warming world. Seasonal environments expose populations to a wide annual temperature variation. To evaluate the simplifying assumption of invariant thermal maxima, we quantified heat tolerance of 26 ant species across three seasons that vary two‐fold in mean temperature. Our ultimate goal was to test the hypothesis that heat tolerance tracks monthly temperature. Ant foragers tested at the end of the summer, in September, had higher average critical thermal maximum (CTmax) compared to those in March and December. Four out of five seasonal generalists, species actively foraging in all three focal months, had, on average, 6°C higher CTmaxin September. The invasive fire ant,
- Editors:
- Cooke, Steve
- Award ID(s):
- 2023571
- Publication Date:
- NSF-PAR ID:
- 10310454
- Journal Name:
- Conservation Physiology
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2051-1434
- Sponsoring Org:
- National Science Foundation
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