Because there are so many humans that someone’s almost definitely gonna have it. If there were like a million people, then we probably wouldn’t see many of these traits, but there are 8 billion people around. That means on average, traits that are one in a million are in 8,000 people. Traits that are one in a billion are still likely to be in a handful of people.
If it’s incompatible with life, no one will have that trait, because no one will be born with it. If it merely prevents you from reproducing, it just won’t be heritable, but the mutations/anomalies will still happen, so people will have them.
I see the general point, it’s just the perforce absolutism of it that I don’t get.
For example, if what you say is true and as long as a large population survives, all its genes necessarily do to, then shouldn’t there be people somewhere in some numbers that exhibit every trait in every one of our evolutionary ancestors? Even in your own examples you only go up to one in a billion, but odds do actually go lower than that.
Because there are so many humans that someone’s almost definitely gonna have it. If there were like a million people, then we probably wouldn’t see many of these traits, but there are 8 billion people around. That means on average, traits that are one in a million are in 8,000 people. Traits that are one in a billion are still likely to be in a handful of people.
If it’s incompatible with life, no one will have that trait, because no one will be born with it. If it merely prevents you from reproducing, it just won’t be heritable, but the mutations/anomalies will still happen, so people will have them.
I see the general point, it’s just the perforce absolutism of it that I don’t get.
For example, if what you say is true and as long as a large population survives, all its genes necessarily do to, then shouldn’t there be people somewhere in some numbers that exhibit every trait in every one of our evolutionary ancestors? Even in your own examples you only go up to one in a billion, but odds do actually go lower than that.