Until recently, the only archaeon for which a bona fide origin of replication 
was reported was Pyrococcus abyssi, where a single origin was identified. 
Although several in silico analyses have suggested that some archaeal species 
might contain more than one origin, this has only been demonstrated recently. 
Two studies have shown that multiple origins of replication function in two 
archaeal species. One study identified two origins of replication in the 
archaeon Sulfolobus solfataricus, whereas a second study used a different 
technique to show that both S. solfataricus and Sulfolobus acidocaldarius have 
three functional origins. These are the first reports of archaea having multiple 
origins. This finding has implications for research on the mechanisms of DNA 
replication and evolution.