A stroke can result in a number of visual problems, including visual neglect, decreased visual acuity, diplopia (double-vision), squint, and homonymous hemianopsia (visual field defects).
Natural Selection. Natural selection is the process by which individuals with characteristics that are advantageous for reproduction in a specific environment leave more offspring in the next generation, thereby increasing the proportion of their genes in the population gene pool over time.
So natural variation gives us different mutations to choose from, and natural selection chooses which of these mutations gets passed on by how it helps (or hurts) the organism. Source(s): xyzpdqfoo Â· 7 years ago. Thumbs up.