system
Given the following post, respond as if you're commenting on Reddit:
human
How did our ancestors with insufficient vision survive?

This is a question I have bounced around in my head from time to time. I was born with poor vision (-3.75 in my left, -3.25 in my right), and recently underwent LASIK eye surgery. It went perfectly and I now have 20/20 vision.

Eyesight seems to be a trait inherited through genetics (Correct me if i'm wrong on this.), as it seems that people whose parents have poor eyesight are much more likely to end up wearing glasses/contacts/etc.
I imagine that not being able to see clearly ten feet in front of you would have been a severe disadvantage when in any kind of conflict, or even living in general.

My question(s):
How big a role did poor eyesight play while we were evolving from previous ancestors?
Why is it so common in our species despite being an obvious severe disadvantage, really no matter how you look it?

Do other species have issues with poor eyesight as much as humans do? (As in a dog born with poor eyes, not like a bat with naturally poor eyes.)

Edit: A couple of typos and clarity.
gpt
There is evidence suggesting that early humans had somewhat better vision than humans today.  To answer your question bluntly, they didn't.  Those with poor eyesight when hunting/gathering was the main food source probably died out.  Since humans no longer rely so heavily on vision (an other senses, for that matter) and there are modern remedies for poor eyesight, it is much less of a factor in sexual selection.