You are currently viewing the summary.
View Full TextLog in to view the full text
AAAS login provides access to Science for AAAS members, and access to other journals in the Science family to users who have purchased individual subscriptions.
More options
Download and print this article for your personal scholarly, research, and educational use.
Buy a single issue of Science for just $15 USD.
Summary
ARNHEM, THE NETHERLANDS-- At a meeting of the European Society for Evolutionary Biology here in August, researchers described studies in viruses that point to a possible resolution of a dispute about the trajectory of evolution. One theory argues that evolution is like a staircase on which organisms evolve through a series of small genetic steps, while another postulates that genetic and environmental changes can derail the evolutionary process, picturing evolution as taking place on a landscape of numerous peaks and valleys where harmful mutations can displace an organism from a peak into a valley. The virus cultures described at the meeting suggested that both metaphors may be valid.
