Why do humans have such poor night vision?
According to part of the theory of evolution the fittest creatures survive to continue their line, leading to current characteristics. If so, would it not follow that current humans should be able to see very well in the dark?
Our ancestors were hunted by predators at night. Lions, Tigers etc. have very good night vision allowing them to hunt nocturnally.
If you read Darwin, because human night vision had not developed to be excellent in the past we would all have been hunted and eaten. Not enough time has passed for our eyesight to have adapted to campfires, candles, naked flame torches etc. which have a limited light output anyway. So why can we not see in the dark?
We're descended from fruit eaters who depended on the color of the fruit to know when it's ready to eat. Color vision using cone cell photoreceptors doesn't work well at night -- the photons of particular frequencies just aren't coming in fast enough to make an image at a useful speed.
So -- we have fewer rod cells in our retinas because our retinas are already crowded with cone cells and the "ganglia cells" that connect to the cone cells.
As for lions and tigers -- we hunt and kill nuisance animals during the day. This has led to lions and tigers evolving to not regard us as part of their usual prey.
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Tiger lighter wind pr torch flame single action blazer US $7.99
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TIGER 64 WP PEARL CHROME CIGAR BLUE TORCH FLAME LIGHTER US $15.99
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Tiger Phantom Double Flame Torch Lighter Humidor US $19.99
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