Common stem cell in heart and lung development explains adaption for life on land

And, the lung is one of the most recent organs to have evolved in mammals and is arguably the most vital for terrestrial life.

http://www.sciencedaily.com/releases/2013/07/130721161714.htm?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+sciencedaily%2Fplants_animals%2Fcell_biology+%28ScienceDaily%3A+Plants+%26+Animals+News+--+Cell+Biology%29