A perfectly preserved amber fossil from Myanmar has been found that provides evidence of the earliest grass specimen ever discovered — about 100 million years old — and even then it was topped by a fungus similar to ergot, a hallucinogen which for eons has been intertwined with animals and humans. Among other things, it gave us the psychedelic drug LSD.
http://www.sciencedaily.com/releases/2015/02/150209130730.htm
