---
_id: '564'
abstract:
- lang: eng
text: "Maladapted individuals can only colonise a new habitat if they can evolve
a\r\npositive growth rate fast enough to avoid extinction, a process known as
evolutionary\r\nrescue. We treat log fitness at low density in the new habitat
as a\r\nsingle polygenic trait and thus use the infinitesimal model to follow
the evolution\r\nof the growth rate; this assumes that the trait values of offspring
of a\r\nsexual union are normally distributed around the mean of the parents’
trait\r\nvalues, with variance that depends only on the parents’ relatedness.
The\r\nprobability that a single migrant can establish depends on just two parameters:\r\nthe
mean and genetic variance of the trait in the source population.\r\nThe chance
of success becomes small if migrants come from a population\r\nwith mean growth
rate in the new habitat more than a few standard deviations\r\nbelow zero; this
chance depends roughly equally on the probability\r\nthat the initial founder
is unusually fit, and on the subsequent increase in\r\ngrowth rate of its offspring
as a result of selection. The loss of genetic variation\r\nduring the founding
event is substantial, but highly variable. With\r\ncontinued migration at rate
M, establishment is inevitable; when migration\r\nis rare, the expected time to
establishment decreases inversely with M.\r\nHowever, above a threshold migration
rate, the population may be trapped\r\nin a ‘sink’ state, in which adaptation
is held back by gene flow; above this\r\nthreshold, the expected time to establishment
increases exponentially with M. This threshold behaviour is captured by a deterministic
approximation,\r\nwhich assumes a Gaussian distribution of the trait in the founder
population\r\nwith mean and variance evolving deterministically. By assuming a
constant\r\ngenetic variance, we also develop a diffusion approximation for the
joint distribution\r\nof population size and trait mean, which extends to include
stabilising\r\nselection and density regulation. Divergence of the population
from its\r\nancestors causes partial reproductive isolation, which we measure
through\r\nthe reproductive value of migrants into the newly established population."
article_processing_charge: No
article_type: original
author:
- first_name: Nicholas H
full_name: Barton, Nicholas H
id: 4880FE40-F248-11E8-B48F-1D18A9856A87
last_name: Barton
orcid: 0000-0002-8548-5240
- first_name: Alison
full_name: Etheridge, Alison
last_name: Etheridge
citation:
ama: Barton NH, Etheridge A. Establishment in a new habitat by polygenic adaptation.
Theoretical Population Biology. 2018;122(7):110-127. doi:10.1016/j.tpb.2017.11.007
apa: Barton, N. H., & Etheridge, A. (2018). Establishment in a new habitat by
polygenic adaptation. Theoretical Population Biology. Academic Press. https://doi.org/10.1016/j.tpb.2017.11.007
chicago: Barton, Nicholas H, and Alison Etheridge. “Establishment in a New Habitat
by Polygenic Adaptation.” Theoretical Population Biology. Academic Press,
2018. https://doi.org/10.1016/j.tpb.2017.11.007.
ieee: N. H. Barton and A. Etheridge, “Establishment in a new habitat by polygenic
adaptation,” Theoretical Population Biology, vol. 122, no. 7. Academic
Press, pp. 110–127, 2018.
ista: Barton NH, Etheridge A. 2018. Establishment in a new habitat by polygenic
adaptation. Theoretical Population Biology. 122(7), 110–127.
mla: Barton, Nicholas H., and Alison Etheridge. “Establishment in a New Habitat
by Polygenic Adaptation.” Theoretical Population Biology, vol. 122, no.
7, Academic Press, 2018, pp. 110–27, doi:10.1016/j.tpb.2017.11.007.
short: N.H. Barton, A. Etheridge, Theoretical Population Biology 122 (2018) 110–127.
date_created: 2018-12-11T11:47:12Z
date_published: 2018-07-01T00:00:00Z
date_updated: 2023-09-11T13:41:22Z
day: '01'
ddc:
- '519'
- '576'
department:
- _id: NiBa
doi: 10.1016/j.tpb.2017.11.007
ec_funded: 1
external_id:
isi:
- '000440392900014'
file:
- access_level: open_access
checksum: 0b96f6db47e3e91b5e7d103b847c239d
content_type: application/pdf
creator: nbarton
date_created: 2019-12-21T09:36:39Z
date_updated: 2020-07-14T12:47:09Z
file_id: '7199'
file_name: bartonetheridge.pdf
file_size: 2287682
relation: main_file
file_date_updated: 2020-07-14T12:47:09Z
has_accepted_license: '1'
intvolume: ' 122'
isi: 1
issue: '7'
language:
- iso: eng
license: https://creativecommons.org/licenses/by-nc/4.0/
month: '07'
oa: 1
oa_version: Submitted Version
page: 110-127
project:
- _id: 25B07788-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '250152'
name: Limits to selection in biology and in evolutionary computation
publication: Theoretical Population Biology
publication_status: published
publisher: Academic Press
publist_id: '7250'
quality_controlled: '1'
related_material:
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relation: research_data
status: public
scopus_import: '1'
status: public
title: Establishment in a new habitat by polygenic adaptation
tmp:
image: /images/cc_by_nc.png
legal_code_url: https://creativecommons.org/licenses/by-nc/4.0/legalcode
name: Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
short: CC BY-NC (4.0)
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 122
year: '2018'
...