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Temperature strongly affects insect development, but plasticity of adult reproductive behaviors can alter the temperatures experienced by earlier life stages. To date, few studies have tested whether adult behavioral plasticity can protect offspring from the warmer,more variable temperatures linked to climate change. Here I discuss laboratory experiments and field manipulations in which my lab has examined whether the adults of three dung beetle species modify their breeding behaviors in response to increases in temperature mean and variance and whether these behavioral shifts can protect dung beetle offspring from temperature changes. Tunnelling dung beetles lay their eggs inside brood balls constructed of dung that are buried below the soil surface. The depth of the brood ball affects the temperatures that the offspring experience and, thus, offspring development. Based on lab and field studies, all three species placed brood balls deeper in the soil in response to warmer and more variable temperatures, but for some species, the greater burial depth came at a cost to brood ball size and/or number, which can impact fitness. Despite greater burial depths, offspring in brood balls in the heated treatments still experienced warmer mean temperatures, which had a large, negative effect on offspring survival of the species with the smallest body size. These findings suggest adult behaviors could partially shield developing offspring from temperature changes.
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Experimental increases in temperature mean and variance alter reproductive behaviours in the dung beetle Phanaeus vindex
Temperature profoundly impacts insect development, but plasticity of reproductive behaviours may mediate the impacts of temperature change on earlier life stages. Few studies have examined the potential for adult behavioural plasticity to buffer offspring from the warmer, more variable temperatures associated with climate change. We used a field manipulation to examine whether the dung beetle Phanaeus vindex alters breeding behaviours in response to temperature changes and whether behavioural shifts protect offspring from temperature changes. Dung beetles lay eggs inside brood balls made of dung that are buried underground. Brood ball depth impacts the temperatures offspring experience with consequences for development. We placed adult females in either control or greenhouse treatments that simultaneously increased temperature mean and variance. We found that females in greenhouse treatments produced more brood balls that were smaller and buried deeper than controls, suggesting brood ball number or burial depth may come at a cost to brood ball size, which can impact offspring nutrition. Despite being buried deeper, brood balls from the greenhouse treatment experienced warmer mean temperatures but similar amplitudes of temperature fluctuation relative to controls. Our findings suggest adult behaviours may partially buffer developing offspring from temperature changes.
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- PAR ID:
- 10380428
- Date Published:
- Journal Name:
- Biology Letters
- Volume:
- 18
- Issue:
- 7
- ISSN:
- 1744-957X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1098/rsbl.2022.0109
