Microbial contributions to host life history trade-offs
Lauren Petrullo1, Gregory F Albery2, Aura Raulo3
1Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, USA; Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Trends in Ecology & Evolution
|July 6, 2026
Summary
Host-associated microbiomes act as resource engines, potentially altering fundamental life history trade-offs for organisms. This microbial influence may reshape evolutionary adaptation by reallocating energy for growth, maintenance, and reproduction.
Area of Science:
- Evolutionary biology
- Microbiome research
- Life history theory
Background:
- Organisms face inherent trade-offs in allocating finite resources to growth, maintenance, and reproduction.
- These resource allocation trade-offs fundamentally constrain evolutionary adaptation.
- Host-associated microbiomes are increasingly recognized for their roles in host physiology and resource metabolism.
Purpose of the Study:
- To propose that host-associated microbiomes can recalibrate fundamental life history trade-offs.
- To explore the potential of microbiomes as dynamic resource engines influencing host evolution.
Main Methods:
- This study is primarily theoretical, synthesizing existing knowledge on resource allocation, life history evolution, and microbiome functions.
- It involves conceptualizing the microbiome's role as an active participant in host resource management.
Main Results:
- Microbiomes can generate and reallocate energy and resources for their hosts.
- This microbial resource management has the potential to alter the constraints imposed by traditional life history trade-offs.
Conclusions:
- Host-associated microbiomes may fundamentally recalibrate life history trade-offs, offering new avenues for understanding host adaptation.
- The integration of microbiome dynamics into life history theory is crucial for a comprehensive understanding of evolution.
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