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Convergent evolution Thu, Mar 31, 2022
Convergent evolution is "the independent evolution of similar features in species of different periods or epochs in time".  A simple example is fish and dolphins.  Fish didn't just become dolphins.  First a non-fish became a fish, then they exited the water, then they grew legs, then they re-entered the water, then they lost their legs.  Both fish and dolphins became water-dwelling fin-propelled animals at completely different points in history and in different branches of the tree of life. 

Pretty much every section of that Wikipedia page made my jaw drop, but the part about light skin color evolving twice was pretty cool. #science

American statistics Thu, Mar 31, 2022
Whenever I hear a statistic about America or Americans, it's pretty much never true.  America isn't really a country, it's actually a shell company containing 50 smaller countries, each with its own economy, geography, and culture.  You can't say "America is mostly [X]" or "Americans are largely [Y]" because it's probably not true for the vast majority of the country, but because of how statistics work, it's sort of true in theory. 

I guess this sort of applies to any large heterogeneous group, and it's especially noticeable for the people who fall outside the norms of whatever statistic you're looking at. #math