Questions on sight and colour

Why do see colour of an object better if you look straight at it?

Why is your vision around the edges of your view less sharp and colourful than your front-on vision?

Explain why the human eye notices more variations in warmer colours than cooler ones?

We have evolved as predators, which means that our ancestors needed to focus on their prey, hence the better vision when focusing straight ahead. However, we later became hunter/gatherers and needed to identify ripe berries, etc, which tend to be red or warm colours.