
http://www.engadget.com/2008/12/08/hp-and-asu-demo-bendable-unbreakable-electronic-displays/
"the hypothalamus and its hormones are not purely vertebrate inventions, but have their evolutionary roots in marine, worm-like ancestors."
"This suggested that hormone-secreting brain centres have arisen after the evolution of vertebrates and invertebrates had split,"
direct source, indirect source: European Molecular Biology Laboratory [EMBL]