Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2021

Erindi/veggspjald / Talk/poster E18

Correspondence of morphological divergence across genotypes in response to diet follows evolutionary divergence of ecologically specialized morphs

Höfundar / Authors: Sarah E. Steele (1), Arnar Pálsson (1)

Starfsvettvangur / Affiliations: 1. University of Iceland

Kynnir / Presenter: Sarah E. Steele

Developmental plasticity has been hypothesized to enable certain species to radiate into multiple ecomorphs. Arctic charr (Salvelinus alpinus) is a widespread, highly plastic and polymorphic organism displaying significant diversity in body size, morphology, diet, life history, and behaviour. Following the arrival of Arctic charr in Iceland approximately 10,000 years ago, anadromous charr radiated into a variety of morphological forms, ecological roles, and habitats. Plasticity is expected to be reduced in these specialized forms and vary by trait. Morphological diversity can be experimentally induced in Arctic charr, allowing study of plasticity within and across morphs in response to environmental stimuli. Using a common-garden rearing experiment, we assessed morphological response to differing diet treatments, investigating divergence of developmental plasticity of specialized morphs from anadromous populations (representing ancestral types) and the genetics of plasticity. Results from growth and head morphology show strong morphological divergence across morphs and diet treatments. We find high correspondence of morphological change in response to diet type across genotypes with evolutionary divergence of specialized morphs. The impact of variation and plasticity during development on phenotypic traits in subsequent life stages can shed light on the interaction of development, environment, and evolution to produce individual phenotypes with different ecological functions.