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Hormones as adaptive control systems in juvenile fish

Growth is an important theme in biology. Physiologists often relate growth rates to hormonal control of essential processes. Ecologists often study growth as a function of gradients or combinations of environmental factors. Fewer studies have investigated the combined effects of environmental and ho...

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Autores principales: Weidner, Jacqueline, Jensen, Camilla Håkonsrud, Giske, Jarl, Eliassen, Sigrunn, Jørgensen, Christian
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Company of Biologists Ltd 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7044463/
https://www.ncbi.nlm.nih.gov/pubmed/31996351
http://dx.doi.org/10.1242/bio.046144
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author Weidner, Jacqueline
Jensen, Camilla Håkonsrud
Giske, Jarl
Eliassen, Sigrunn
Jørgensen, Christian
author_facet Weidner, Jacqueline
Jensen, Camilla Håkonsrud
Giske, Jarl
Eliassen, Sigrunn
Jørgensen, Christian
author_sort Weidner, Jacqueline
collection PubMed
description Growth is an important theme in biology. Physiologists often relate growth rates to hormonal control of essential processes. Ecologists often study growth as a function of gradients or combinations of environmental factors. Fewer studies have investigated the combined effects of environmental and hormonal control on growth. Here, we present an evolutionary optimization model of fish growth that combines internal regulation of growth by hormone levels with the external influence of food availability and predation risk. The model finds a dynamic hormone profile that optimizes fish growth and survival up to 30 cm, and we use the probability of reaching this milestone as a proxy for fitness. The complex web of interrelated hormones and other signalling molecules is simplified to three functions represented by growth hormone, thyroid hormone and orexin. By studying a range from poor to rich environments, we find that the level of food availability in the environment results in different evolutionarily optimal strategies of hormone levels. With more food available, higher levels of hormones are optimal, resulting in higher food intake, standard metabolism and growth. By using this fitness-based approach we also find a consequence of evolutionary optimization of survival on optimal hormone use. Where foraging is risky, the thyroid hormone can be used strategically to increase metabolic potential and the chance of escaping from predators. By comparing model results to empirical observations, many mechanisms can be recognized, for instance a change in pace-of-life due to resource availability, and reduced emphasis on reserves in more stable environments. This article has an associated First Person interview with the first author of the paper.
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spelling pubmed-70444632020-02-27 Hormones as adaptive control systems in juvenile fish Weidner, Jacqueline Jensen, Camilla Håkonsrud Giske, Jarl Eliassen, Sigrunn Jørgensen, Christian Biol Open Research Article Growth is an important theme in biology. Physiologists often relate growth rates to hormonal control of essential processes. Ecologists often study growth as a function of gradients or combinations of environmental factors. Fewer studies have investigated the combined effects of environmental and hormonal control on growth. Here, we present an evolutionary optimization model of fish growth that combines internal regulation of growth by hormone levels with the external influence of food availability and predation risk. The model finds a dynamic hormone profile that optimizes fish growth and survival up to 30 cm, and we use the probability of reaching this milestone as a proxy for fitness. The complex web of interrelated hormones and other signalling molecules is simplified to three functions represented by growth hormone, thyroid hormone and orexin. By studying a range from poor to rich environments, we find that the level of food availability in the environment results in different evolutionarily optimal strategies of hormone levels. With more food available, higher levels of hormones are optimal, resulting in higher food intake, standard metabolism and growth. By using this fitness-based approach we also find a consequence of evolutionary optimization of survival on optimal hormone use. Where foraging is risky, the thyroid hormone can be used strategically to increase metabolic potential and the chance of escaping from predators. By comparing model results to empirical observations, many mechanisms can be recognized, for instance a change in pace-of-life due to resource availability, and reduced emphasis on reserves in more stable environments. This article has an associated First Person interview with the first author of the paper. The Company of Biologists Ltd 2020-02-17 /pmc/articles/PMC7044463/ /pubmed/31996351 http://dx.doi.org/10.1242/bio.046144 Text en © 2020. Published by The Company of Biologists Ltd http://creativecommons.org/licenses/by/4.0This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.
spellingShingle Research Article
Weidner, Jacqueline
Jensen, Camilla Håkonsrud
Giske, Jarl
Eliassen, Sigrunn
Jørgensen, Christian
Hormones as adaptive control systems in juvenile fish
title Hormones as adaptive control systems in juvenile fish
title_full Hormones as adaptive control systems in juvenile fish
title_fullStr Hormones as adaptive control systems in juvenile fish
title_full_unstemmed Hormones as adaptive control systems in juvenile fish
title_short Hormones as adaptive control systems in juvenile fish
title_sort hormones as adaptive control systems in juvenile fish
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7044463/
https://www.ncbi.nlm.nih.gov/pubmed/31996351
http://dx.doi.org/10.1242/bio.046144
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