Complex sentence: In the article, researchers Michael Worobey and colleagues verified the existence of SIVcpz in indigenous chimps from the Kisangani area but claimed that phylogenetic analyses of said virus indicated that it was nested within an entirely different clade of SIVcpz than the strain that includes HIV-1.
Split into simpler sentences: In the article, researchers Michael Worobey and colleagues verified the existence of SIVcpz in Kisangani chimps. However, through phylogenetic analyses of the virus, they found the SIVcpz that infected these chimps was nested within an entirely different clade of SIVcpz than the strain that includes HIV-1.