Evidence Found for Planet-Cooling Asteroid 12,900 Years Ago (which prompted the agricultural revolution..?) - http://www.scientificamerican.com/article.cfm?id=evidence-found-for-planet-cooling-asteroid-12900-years-ago&WT.mc_id=SA_sharetool_Twitter …
10:39 AM - 3 Sep 2013
0 replies
0 retweets
1 like
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.