To give you a sense of just how rapidly these numbers increase, there are more
13-species trees than there are people on the planet (just shy of 7 billion at present).
There are more 22-species trees than there are stars in the universe (approximately 1023). There are more 36-species trees than there are water molecules in all of
Earth’s oceans (approximately 1047). There are more 53-species trees than there are
atoms in the universe (approximately 1080).
Evolution - Carl Bergstrom e Lee Allan Dugatkin - W.W. Norton & Company - 1st Ed, 2012
