Tuesday, Jul 28, 2026 The claims desk. Receipts included. POWERED BY LENZ ↗
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The Claim

Thermal selection and sexual selection can act in opposite directions in shaping organismal phenotypes.

Verified by Lenz ·

The Short Version

The evidence strongly supports the possibility of opposition between thermal selection and sexual selection. Multiple empirical and review sources show cases where traits favored for mating success are penalized under thermal stress, reducing heat tolerance, survival, or performance. Because the claim says these forces can act in opposite directions, documented examples are sufficient to establish it.

Caveats

  • The strongest evidence comes from specific systems, especially insects such as Drosophila, so the exact mechanisms and strength of opposition may vary across taxa.
  • Opposition is not universal: some studies show buffering, context dependence, or no net adaptation effect under warming rather than persistent conflict.
  • Several listed items are low-reliability background sources, but the conclusion rests on peer-reviewed primary studies and reviews, not on those weaker sources.

The Receipts

  1. Evolutionary interactions between thermal ecology and sexual selection

    Wiley Online Library

  2. Experimental evolution reveals trade-offs between sexual selection and heat tolerance in Drosophila prolongata

    PubMed

  3. Temperature as a modulator of sexual selection

    Wiley Online Library

  4. Transcriptomics of differences in thermal plasticity associated with selection for an exaggerated male sexual trait

    Nature

  5. Experimental evolution reveals trade-offs between sexual selection, thermal stress, and male reproductive success

    Evolution

  6. Thermal phenotypic plasticity of pre- and post-copulatory male harm in Drosophila melanogaster

    eLife

  7. Natural and sexual selection on phenotypic plasticity favour thermal canalization

    bioRxiv

  8. Natural and sexual selection drive multivariate phenotypic divergence along climatic gradients in a vertebrate

    Evolution

  9. Sexual selection buffers the negative consequences of population fragmentation on adaptive plastic responses to increasing temperatures

    Evolution

  10. The importance of pre- and postcopulatory sexual selection promoting adaptation to increasing temperatures

    Current Zoology

+ 18 more sources — see the full list on Lenz

Filed Under

Sexual SelectionThermal Selection

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