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Title: Unpredictable soil conditions can affect the prevalence of a microbial symbiosis
The evolution of symbiotic interactions may be affected by unpredictable conditions. However, a link between prevalence of these conditions and symbiosis has not been widely demonstrated. We test for these associations usingDictyostelium discoideumsocial amoebae and their bacterial endosymbionts.D. discoideumcommonly hosts endosymbiotic bacteria from three taxa:Paraburkholderia, Amoebophilusand Chlamydiae. Three species of facultativeParaburkholderiaendosymbionts are the best studied and give hosts the ability to carry prey bacteria through the dispersal stage to new environments.Amoebophilusand Chlamydiae are obligate endosymbiont lineages with no measurable impact on host fitness. We tested whether the frequency of both single infections and coinfections of these symbionts were associated with the unpredictability of their soil environments by using symbiont presence-absence data fromD. discoideumisolates from 21 locations across the eastern United States. We found that symbiosis across all infection types, symbiosis withAmoebophilusand Chlamydiae obligate endosymbionts, and symbiosis involving coinfections were not associated with any of our measures. However, unpredictable precipitation was associated with symbiosis in two species ofParaburkholderia, suggesting a link between unpredictable conditions and symbiosis.  more » « less
Award ID(s):
2237266
PAR ID:
10572038
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
PeerJ
Date Published:
Journal Name:
PeerJ
Volume:
12
ISSN:
2167-8359
Page Range / eLocation ID:
e17445
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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