Lincoln is only relevant for the US, Darwin was important for the whole World.
?! Only for the US?
Lincoln preserved the union. If the Lincoln hadn't the balls to suspend some liberties, exercise a little tyranny in the name of preservation of the constitution, if the GOP had lost its will to fight after the first couple of humiliating defeats of the Army of the Potomac, if the people hadn't such an shrewd president, the United States of America would have disintegrated. The precedent would have been set. Any state could at any moment decide it no longer wanted any part of the congress. The North American continent would have reverted to being an imperial European playground, with the attendant petty skirmishes and major wars. And who would have helped the UK and the French defeat the Germans and Austrians in the Great War? And even if the French and English had defeated the Germans, the humiliation to the German people at Versailles would have been even greater without Wilson, and fascism would have spread with even more intensity. And who, then, would have helped the Russians and English defeat the Nazis? And who would have helped the Chinese keep the Great Empire of the Rising Sun at bay? And what about the Cold War? Wait, what Cold War? Without a stable counterbalance to the spread of Communism--that is, without a stable and powerful United States--there would have been no Cold War. Right now, there would probably be two great Superpowers: one very Red and very Russian, and one very Black and very German. Both authoritarian and expansionist, and both, probably, with an incredible arsenal of weapons. Hey, look on the bright side: at least no one would be worrying about the likes of Al Qaeda.
Only relevant to the US?! Indeed.
Get smart, man. Lincoln has had a far, far greater impact than that hack Charles Darwin whole stole Malthus' ideas about natural selection and took credit for them. With or without Darwin, your liberties would still be secure. Without Lincoln, you'd be dodging German and Russian nukes.