Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2023

Sources of egg size variation in captive Arctic charr

Höfundar / Authors: Paul V Debes, Sabine BC Lobligeois & Einar Svavarsson

Starfsvettvangur / Affiliations: 1. Hólar University

Kynnir / Presenter: Paul Vincent Debes

Egg size is a complex life-history trait that is strongly associated with fitness via offspring traits in many species. In fishes, magnitudes of environmental and genetic effects on egg size variation, and thus ecological vs. evolutionary importance, remain uncertain. This uncertainty may also exist because egg size is expressed solely by females after reaching sexual maturity, whereby later sexual maturation timing usually incurs larger egg size, and maturation timing variation is also a complex trait. We analysed breeding programme data from 15 cohorts of Arctic charr to disentangle environmental from genetic sources on egg size variation and tested whether and how other traits expressed before and at sexual maturity, including maturation age, affect egg size variation. We present estimates of environmental and genetic components for egg size variation and its covariation with other traits. The results contribute to an overall understanding of eggs size as a complex life history trait and the ability of predicting its evolutionary potential in nature and how well it responds to selective breeding in captivity.