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Related Experiment Video

Updated: Jun 2, 2026

Protocols for Investigating the Host-tissue Distribution, Transmission-mode, and Effect on the Host Fitness of a Densovirus in the Cotton Bollworm

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Published on: April 12, 2017

Two-stepping through time: mammals and viruses.

Nicholas R Meyerson¹, Sara L Sawyer

¹Section of Molecular Genetics and Microbiology, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA.

Trends in Microbiology

|May 3, 2011

Summary

Ancient virus fossils reveal viruses are older and more widespread than previously thought. A modified evolutionary arms race model suggests host constraints may explain viral evolution.

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Area of Science:

Virology
Evolutionary Biology
Genomics

Background:

Ancient virus genomes are increasingly identified within animal DNA.
This discovery indicates that many mammalian virus families are older and more common than previously understood.
The long-term interaction between viruses and hosts resembles a genetic arms race.

Purpose of the Study:

To review recent data on host evolutionary strategies against viruses.
To propose a modified arms race model that accounts for host constraints on viral evolution.
To enable more accurate forecasting of future virus evolution.

Main Methods:

Review of existing scientific literature on viral fossils and host-virus evolutionary dynamics.
Analysis of data on the evolutionary rates of hosts versus viruses.
Development of a theoretical model to explain host-virus co-evolution.

Main Results:

Mammalian hosts have evolved strategies to keep pace with rapidly evolving viruses, despite slower evolutionary rates.
A modified arms race model, incorporating host-imposed constraints, provides a plausible explanation for observed viral evolution.
This model suggests that viral evolutionary pathways are not unlimited.

Conclusions:

Host genomes contain ancient viral fossils that offer insights into evolutionary history.
A revised understanding of the host-virus evolutionary arms race is necessary.
The proposed model can improve predictions of viral evolution and potential future outbreaks.