Space/Science
http://www.theaustralian.news.com.au/story/0,25197,24625663-2703,00.html it is reported that all chloroplasts are so genetically similar that they must have come from a single cellular ancestor and (allegedly) from a single symbiosis event. I'm not so sure about the latter - it seems to me possible that a single ancestral species could have been "primed" for symbiosis and could then have experienced muliple symbiosis-initiating events, but perhaps this is stretching credibility. either way, it was an interesting and fundamentally important event for all life on Earth. There may be similar storiers yet to be told about Mitochondria and other organelles of Eucaryotes (which were all originally independent organisms)
