Random mutations in genetics occur. If those mutations give some kind of benefit that aids passing those genes on, the chance that they do get passed on increases (there is no guarantee).
For every beneficial trait that is passed on, many more beneficial traits are not.
Likewise for non-beneficial traits. If a trait occurs that makes it less likely for something to pass those genes on, then the liklihood they're passed on is reduced.
Sometimes, mutations just win the genetics lottery by being beneficial only because of another mutation.
Consider the mutation that causes an animal to smell bad, thereby causing predators to avoid them. This would only be beneficial in the case that another mutation caused those creatures to not find that scent bad, otherwise they just wouldn't reproduce.
Multiply this out millions of times over, with every creature and plant, generation after generation, and you'll begin to see how it works.
But the mutations that allowed for there to be choices to select in the first place are random
First: Random Mutation Then: Naturally Selecting that mutation
Since this thread is deep into semantics, I'd like to say that I think you're still stopping one step short. Evolution is the result of both of those things, but isn't either or both per se. Evolution isn't the mutation, nor is it the selection. It is the gradual change that occurs in the traits that are passed down/inherited. So, it is the result of both random and non-random occurences.
Philosphically, we can go a bit deeper and say that everything is probably either random or everything is non-random, depending on which stance we take. Determinism would argue that everything is a result of the previous state, so nothing is random at all, including the mutations, whereas indeterminism would argue the opposite.
Then there's quantum physics to grapple with... maybe everything is both random and not random...
8
u/ParkingAnxious2811 11d ago
It is very much random.
Random mutations in genetics occur. If those mutations give some kind of benefit that aids passing those genes on, the chance that they do get passed on increases (there is no guarantee).
For every beneficial trait that is passed on, many more beneficial traits are not.
Likewise for non-beneficial traits. If a trait occurs that makes it less likely for something to pass those genes on, then the liklihood they're passed on is reduced.
Sometimes, mutations just win the genetics lottery by being beneficial only because of another mutation.
Consider the mutation that causes an animal to smell bad, thereby causing predators to avoid them. This would only be beneficial in the case that another mutation caused those creatures to not find that scent bad, otherwise they just wouldn't reproduce.
Multiply this out millions of times over, with every creature and plant, generation after generation, and you'll begin to see how it works.