A1 Journal article (refereed)
The balance model of honest sexual signaling (2022)

Fromhage, L., & Henshaw, J. M. (2022). The balance model of honest sexual signaling. Evolution, 76(3), 445-454. https://doi.org/10.1111/evo.14436

JYU authors or editors

Fromhage, Lutz

Publication details

All authors or editors: Fromhage, Lutz; Henshaw, Jonathan M.

Journal or series: Evolution

ISSN: 0014-3820

eISSN: 1558-5646

Publication year: 2022

Publication date: 24/01/2022

Volume: 76

Issue number: 3

Pages range: 445-454

Publisher: Wiley-Blackwell

Publication country: United Kingdom

Publication language: English

DOI: https://doi.org/10.1111/evo.14436

Publication open access: Openly available

Publication channel open access: Partially open access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/79551

Abstract

Costly signalling theory is based on the idea that individuals may signal their quality to potential mates and that the signal's costliness plays a crucial role in maintaining information content (‘honesty’) over evolutionary time. Whereas costly signals have traditionally been described as ‘handicaps’, here we present mathematical results that motivate an alternative interpretation. We show that under broad conditions, the multiplicative nature of fitness selects for roughly balanced investments in mating success and viability, thereby generating a positive correlation between signal size and quality. This balancing tendency occurs because selection for increased investment in a fitness component diminishes with the absolute level of investment in that component, such that excessively biased investments are penalised. The resulting interpretation of costly signals as balanced (albeit not necessarily equal) investments may be a widely applicable alternative to the traditional ‘handicap’ metaphor, which has been criticised for its non-Darwinian connotation of selection for ‘waste’ rather than efficiency. We predict that accelerating returns on viability are necessary to undermine honesty. This prediction depends crucially on the assumption that mating success and viability contribute multiplicatively (rather than additively) to an individual's fitness.

Keywords: evolution; sexual selection; signals

Free keywords: sexual signalling

Fields of science: