How important is hidden phenotypic plasticity arising from alternative but converging developmental trajectories, and what limits it?

Metcalfe, N. (2024) How important is hidden phenotypic plasticity arising from alternative but converging developmental trajectories, and what limits it? Journal of Experimental Biology, 227(Sup_1), jeb246010. (doi: 10.1242/jeb.246010)

Abstract

Developmental plasticity ­– the capacity for a genotype to develop into different phenotypes, depending on the environment – is typically viewed from the perspective of the resulting phenotype. Thus, if development is viewed as a trajectory towards a target, then developmental plasticity allows environmentally induced alterations to the target. However, there can also be variations in the trajectory. This is seen with compensatory responses, for instance where growth accelerates after an earlier period of food shortage, or where investment in sexual ornaments is maintained even when resources are limiting. If the compensation is complete, the adult phenotype can appear ‘normal’ (i.e. the different developmental trajectories converge on the same target). However, alternative trajectories to a common target can have multiple long-term consequences, including altered physiological programming and rates of senescence, possibly owing to trade-offs between allocating resources to the prioritized trait versus to body maintenance. This suggests that plasticity in developmental trajectories towards a common target leads to variation in the resilience and robustness of the adult body. This form of developmental plasticity is far more hidden than plasticity in final adult target, but it may be more common. Here, I discuss the causes, consequences and limitations of these different kinds of plasticity, with a special focus on whether they are likely to be adaptive. I emphasize the need to study plasticity in developmental trajectories, and conclude with suggestions for future research to tease apart the different forms of developmental plasticity and the factors that influence their evolution and expression.

• Item Type: Articles
• Additional Information: Funding was provided by Advanced Grant 834653 from the European Research Council while planning, writing and revising this Review. Open access funding provided by University of Glasgow.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Metcalfe, Professor Neil
• Authors: Metcalfe, N.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Journal of Experimental Biology
• Publisher: Company of Biologists
• ISSN: 0022-0949
• ISSN (Online): 1477-9145
• Copyright Holders: Copyright © 2024. Published by The Company of Biologists Ltd
• First Published: First published in Journal of Experimental Biology 227 (Suppl_1): jeb246010.
• Publisher Policy: Reproduced under a Creative Commons licence