We want to show differences between HIV and SIV as demonstrated by data we present. Using ImageJ we counted the number of spikes from tomograms of HIV-1 and SIVmac239 published in PNAS (Zhu, P. et al, PNAS, 100(26): 15812, 2003). We then looked at available PDB data for viral spikes and present PyMOL and Consurf images of SIV gp41, HIV gp41 and HIV gp120 protein components. Both SIV and HIV have gp120 and gp41 which is cleaved from gp160. Our concept map created with Cmap uses current data on SIV and HIV in Proteopedia.