Evolution and the Ebola Virus: Pacing a Small Cage

I received a request to comment on the evolution of the Ebola virus. The best, most recent work, which sequenced and compared 99 entire virus genomes, was published in Science last month: "Genomic surveillance elucidates Ebola virus origin and transmission during the 2014 outbreak." It came at a very high cost -- five co-authors actually died of Ebola in the course of the work.

The paper is mostly concerned with tracing the timing and spread of the virus. The authors show that the virus is a...