Drivers of diversity in individual life courses:Sensitivity of the population entropy of a Markov chain
Individuals differ in their life courses, but how this diversity is generated, how it has evolved and how it is maintained is less understood. However, this understanding is crucial to comprehend evolutionary and ecological population dynamics. In structured populations, individual life courses repr...
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Online Access: | https://portal.findresearcher.sdu.dk/da/publications/22cb94db-0336-4065-84eb-f52942f037c7 https://doi.org/10.1016/j.tpb.2020.01.003 https://www.biorxiv.org/content/biorxiv/early/2017/09/13/188276.full.pdf https://doi.org/10.1101/188276 |
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ftsydanskunivpub:oai:sdu.dk:publications/22cb94db-0336-4065-84eb-f52942f037c7 2024-09-15T18:02:39+00:00 Drivers of diversity in individual life courses:Sensitivity of the population entropy of a Markov chain Steiner, Ulrich K. Tuljapurkar, Shripad 2020-06 https://portal.findresearcher.sdu.dk/da/publications/22cb94db-0336-4065-84eb-f52942f037c7 https://doi.org/10.1016/j.tpb.2020.01.003 https://www.biorxiv.org/content/biorxiv/early/2017/09/13/188276.full.pdf https://doi.org/10.1101/188276 eng eng https://portal.findresearcher.sdu.dk/da/publications/22cb94db-0336-4065-84eb-f52942f037c7 info:eu-repo/semantics/closedAccess Steiner , U K & Tuljapurkar , S 2020 , ' Drivers of diversity in individual life courses : Sensitivity of the population entropy of a Markov chain ' , Theoretical Population Biology , vol. 133 , pp. 159-167 . https://doi.org/10.1016/j.tpb.2020.01.003 Biodemography Life course Life history evolution Neutral variability Population entropy Sensitivity article 2020 ftsydanskunivpub https://doi.org/10.1016/j.tpb.2020.01.00310.1101/188276 2024-08-19T23:51:23Z Individuals differ in their life courses, but how this diversity is generated, how it has evolved and how it is maintained is less understood. However, this understanding is crucial to comprehend evolutionary and ecological population dynamics. In structured populations, individual life courses represent sequences of stages that end in death. These life course trajectories or sequences can be described by a Markov chain and individuals diversify over the course of their lives by transitioning through diverse discrete stages. The rate at which stage sequences diversify with age can be quantified by the population entropy of a Markov chain. Here, we derive sensitivities of the population entropy of a Markov chain to identify which stage transitions generate – or contribute – most to diversification in stage sequences, i.e. life courses. We then use these sensitivities to reveal potential selective forces on the dynamics of life courses. To do so we correlated the sensitivity of each matrix element (stage transition) with respect to the population entropy, to its sensitivity with respect to fitness λ, the population growth rate. Positive correlation between the two sensitivities would suggest that the stage transitions that selection has acted most strongly on (high sensitivities with respect to λ) are also those that contributed most to the diversification of life courses. Using an illustrative example on a seabird population, the Thick-billed Murres on Coats Island, that is structured by reproductive stages, we show that the most influential stage transitions for diversification of life courses are not correlated with the most influential transitions for population growth. Our finding suggests that observed diversification in life courses is neutral rather than adaptive, note this does not imply that the life histories themselves are not adaptive. We are at an early stage of understanding how individual level dynamics shape ecological and evolutionary dynamics, and many discoveries await. Article in Journal/Newspaper Coats Island University of Southern Denmark Research Portal Theoretical Population Biology 133 159 167 |
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Open Polar |
collection |
University of Southern Denmark Research Portal |
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ftsydanskunivpub |
language |
English |
topic |
Biodemography Life course Life history evolution Neutral variability Population entropy Sensitivity |
spellingShingle |
Biodemography Life course Life history evolution Neutral variability Population entropy Sensitivity Steiner, Ulrich K. Tuljapurkar, Shripad Drivers of diversity in individual life courses:Sensitivity of the population entropy of a Markov chain |
topic_facet |
Biodemography Life course Life history evolution Neutral variability Population entropy Sensitivity |
description |
Individuals differ in their life courses, but how this diversity is generated, how it has evolved and how it is maintained is less understood. However, this understanding is crucial to comprehend evolutionary and ecological population dynamics. In structured populations, individual life courses represent sequences of stages that end in death. These life course trajectories or sequences can be described by a Markov chain and individuals diversify over the course of their lives by transitioning through diverse discrete stages. The rate at which stage sequences diversify with age can be quantified by the population entropy of a Markov chain. Here, we derive sensitivities of the population entropy of a Markov chain to identify which stage transitions generate – or contribute – most to diversification in stage sequences, i.e. life courses. We then use these sensitivities to reveal potential selective forces on the dynamics of life courses. To do so we correlated the sensitivity of each matrix element (stage transition) with respect to the population entropy, to its sensitivity with respect to fitness λ, the population growth rate. Positive correlation between the two sensitivities would suggest that the stage transitions that selection has acted most strongly on (high sensitivities with respect to λ) are also those that contributed most to the diversification of life courses. Using an illustrative example on a seabird population, the Thick-billed Murres on Coats Island, that is structured by reproductive stages, we show that the most influential stage transitions for diversification of life courses are not correlated with the most influential transitions for population growth. Our finding suggests that observed diversification in life courses is neutral rather than adaptive, note this does not imply that the life histories themselves are not adaptive. We are at an early stage of understanding how individual level dynamics shape ecological and evolutionary dynamics, and many discoveries await. |
format |
Article in Journal/Newspaper |
author |
Steiner, Ulrich K. Tuljapurkar, Shripad |
author_facet |
Steiner, Ulrich K. Tuljapurkar, Shripad |
author_sort |
Steiner, Ulrich K. |
title |
Drivers of diversity in individual life courses:Sensitivity of the population entropy of a Markov chain |
title_short |
Drivers of diversity in individual life courses:Sensitivity of the population entropy of a Markov chain |
title_full |
Drivers of diversity in individual life courses:Sensitivity of the population entropy of a Markov chain |
title_fullStr |
Drivers of diversity in individual life courses:Sensitivity of the population entropy of a Markov chain |
title_full_unstemmed |
Drivers of diversity in individual life courses:Sensitivity of the population entropy of a Markov chain |
title_sort |
drivers of diversity in individual life courses:sensitivity of the population entropy of a markov chain |
publishDate |
2020 |
url |
https://portal.findresearcher.sdu.dk/da/publications/22cb94db-0336-4065-84eb-f52942f037c7 https://doi.org/10.1016/j.tpb.2020.01.003 https://www.biorxiv.org/content/biorxiv/early/2017/09/13/188276.full.pdf https://doi.org/10.1101/188276 |
genre |
Coats Island |
genre_facet |
Coats Island |
op_source |
Steiner , U K & Tuljapurkar , S 2020 , ' Drivers of diversity in individual life courses : Sensitivity of the population entropy of a Markov chain ' , Theoretical Population Biology , vol. 133 , pp. 159-167 . https://doi.org/10.1016/j.tpb.2020.01.003 |
op_relation |
https://portal.findresearcher.sdu.dk/da/publications/22cb94db-0336-4065-84eb-f52942f037c7 |
op_rights |
info:eu-repo/semantics/closedAccess |
op_doi |
https://doi.org/10.1016/j.tpb.2020.01.00310.1101/188276 |
container_title |
Theoretical Population Biology |
container_volume |
133 |
container_start_page |
159 |
op_container_end_page |
167 |
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1810440084569194496 |