Genotype-by-environment interactions and adaptation to local temperature affect immunity and fecundity in Drosophila melanogaster.
Natural populations of most organisms harbor substantial genetic variation for resistance to infection. The continued existence of such variation is unexpected under simple evolutionary models that either posit direct and continuous natural selection on the immune system or an evolved life history &...
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Public Library of Science (PLoS)
2008-03-01
|
Series: | PLoS Pathogens |
Online Access: | http://europepmc.org/articles/PMC2265416?pdf=render |
_version_ | 1811218162717294592 |
---|---|
author | Brian P Lazzaro Heather A Flores James G Lorigan Christopher P Yourth |
author_facet | Brian P Lazzaro Heather A Flores James G Lorigan Christopher P Yourth |
author_sort | Brian P Lazzaro |
collection | DOAJ |
description | Natural populations of most organisms harbor substantial genetic variation for resistance to infection. The continued existence of such variation is unexpected under simple evolutionary models that either posit direct and continuous natural selection on the immune system or an evolved life history "balance" between immunity and other fitness traits in a constant environment. However, both local adaptation to heterogeneous environments and genotype-by-environment interactions can maintain genetic variation in a species. In this study, we test Drosophila melanogaster genotypes sampled from tropical Africa, temperate northeastern North America, and semi-tropical southeastern North America for resistance to bacterial infection and fecundity at three different environmental temperatures. Environmental temperature had absolute effects on all traits, but there were also marked genotype-by-environment interactions that may limit the global efficiency of natural selection on both traits. African flies performed more poorly than North American flies in both immunity and fecundity at the lowest temperature, but not at the higher temperatures, suggesting that the African population is maladapted to low temperature. In contrast, there was no evidence for clinal variation driven by thermal adaptation within North America for either trait. Resistance to infection and reproductive success were generally uncorrelated across genotypes, so this study finds no evidence for a fitness tradeoff between immunity and fecundity under the conditions tested. Both local adaptation to geographically heterogeneous environments and genotype-by-environment interactions may explain the persistence of genetic variation for resistance to infection in natural populations. |
first_indexed | 2024-04-12T07:04:48Z |
format | Article |
id | doaj.art-632c905687974c1dae2e3da89630149a |
institution | Directory Open Access Journal |
issn | 1553-7366 1553-7374 |
language | English |
last_indexed | 2024-04-12T07:04:48Z |
publishDate | 2008-03-01 |
publisher | Public Library of Science (PLoS) |
record_format | Article |
series | PLoS Pathogens |
spelling | doaj.art-632c905687974c1dae2e3da89630149a2022-12-22T03:42:50ZengPublic Library of Science (PLoS)PLoS Pathogens1553-73661553-73742008-03-0143e100002510.1371/journal.ppat.1000025Genotype-by-environment interactions and adaptation to local temperature affect immunity and fecundity in Drosophila melanogaster.Brian P LazzaroHeather A FloresJames G LoriganChristopher P YourthNatural populations of most organisms harbor substantial genetic variation for resistance to infection. The continued existence of such variation is unexpected under simple evolutionary models that either posit direct and continuous natural selection on the immune system or an evolved life history "balance" between immunity and other fitness traits in a constant environment. However, both local adaptation to heterogeneous environments and genotype-by-environment interactions can maintain genetic variation in a species. In this study, we test Drosophila melanogaster genotypes sampled from tropical Africa, temperate northeastern North America, and semi-tropical southeastern North America for resistance to bacterial infection and fecundity at three different environmental temperatures. Environmental temperature had absolute effects on all traits, but there were also marked genotype-by-environment interactions that may limit the global efficiency of natural selection on both traits. African flies performed more poorly than North American flies in both immunity and fecundity at the lowest temperature, but not at the higher temperatures, suggesting that the African population is maladapted to low temperature. In contrast, there was no evidence for clinal variation driven by thermal adaptation within North America for either trait. Resistance to infection and reproductive success were generally uncorrelated across genotypes, so this study finds no evidence for a fitness tradeoff between immunity and fecundity under the conditions tested. Both local adaptation to geographically heterogeneous environments and genotype-by-environment interactions may explain the persistence of genetic variation for resistance to infection in natural populations.http://europepmc.org/articles/PMC2265416?pdf=render |
spellingShingle | Brian P Lazzaro Heather A Flores James G Lorigan Christopher P Yourth Genotype-by-environment interactions and adaptation to local temperature affect immunity and fecundity in Drosophila melanogaster. PLoS Pathogens |
title | Genotype-by-environment interactions and adaptation to local temperature affect immunity and fecundity in Drosophila melanogaster. |
title_full | Genotype-by-environment interactions and adaptation to local temperature affect immunity and fecundity in Drosophila melanogaster. |
title_fullStr | Genotype-by-environment interactions and adaptation to local temperature affect immunity and fecundity in Drosophila melanogaster. |
title_full_unstemmed | Genotype-by-environment interactions and adaptation to local temperature affect immunity and fecundity in Drosophila melanogaster. |
title_short | Genotype-by-environment interactions and adaptation to local temperature affect immunity and fecundity in Drosophila melanogaster. |
title_sort | genotype by environment interactions and adaptation to local temperature affect immunity and fecundity in drosophila melanogaster |
url | http://europepmc.org/articles/PMC2265416?pdf=render |
work_keys_str_mv | AT brianplazzaro genotypebyenvironmentinteractionsandadaptationtolocaltemperatureaffectimmunityandfecundityindrosophilamelanogaster AT heatheraflores genotypebyenvironmentinteractionsandadaptationtolocaltemperatureaffectimmunityandfecundityindrosophilamelanogaster AT jamesglorigan genotypebyenvironmentinteractionsandadaptationtolocaltemperatureaffectimmunityandfecundityindrosophilamelanogaster AT christopherpyourth genotypebyenvironmentinteractionsandadaptationtolocaltemperatureaffectimmunityandfecundityindrosophilamelanogaster |