SN Online SN Online Share this:EmailFacebookTwitterPinterestPocketRedditPrint By Science News April 4, 2013 at 12:31 pm BECOMING HUMANLearn how people have been driving species to extinction since the Stone Age in a new column by Erin Wayman. Rufus Isaacs LIFE Wild insects are a key to bigger harvests. See “Native pollinators boost crop yields worldwide.” SCIENCE & SOCIETYBy tracking tweets, researchers identify communities. Read “Twitter maps New York City, language by language.” BODY & BRAINIn developing rat and monkey brains, cells called microglia prune excess growth. See “Immune cells chow down on living brain.”