Two Birthdays - February 12

Two men were born on February 12 in 1809:  Abraham Lincoln and Charles Robert Darwin.

Abraham Lincoln

Lincoln was a focal point during the Civil War.  He made decisions that probably no other man could have made.  He was important.  Very likely the north would not have won the war without him.

Darwin at the time of his
trip around the world.

Darwin was - believe it or not - not as important.  He was rich enough to not have to work.  He was immensely curious.  He devoted his life to amassing data to support his hypothesis that evolution was driven by competition for the means of survival and reproduction. 

Ultimately he gave us the theory that evolution occurs through natural selection of variations.

(Note that evolution was a given.  A theory explains how it happens.  At the time there were several competing theories about the cause of evolution.  And yes, just like every experiment so far has proven Einstein's theory of relativity, so has every experiment so far shown that Darwin was correct.)

Alfred Russel Wallace also had
the idea of natural selection, and
wrote about it in almost the
exact same words as Dawrin

But natural selection was not Darwin's exclusive idea.  Alfred Russel Wallace wrote to Darwin just before Darwin announced his theory, with a paper that stated exactly the same thing.  The two papers were presented together.  Each edition of The Origin of Species added more names of scientists that Darwin acknowledged were working along the same lines.

When the world is ready for an idea, someone will present it.  Many did.  Darwin had the time, money, and influential friends to make sure that his name was attached to the theory.  His lifetime of research is his real legacy.