<span>Ecological surplus is when a country has more natural resources than it needs. Ecological deficit is when a country has less than it needs. How much of it's resources a country uses is it's environmental footprint, which determines whether it's an ecological surplus or deficit.</span>
Binocular cues include stereopsis, eye convergence, disparity, and yielding depth from binocular vision through exploitation of parallax. Monocular cues include size: distant objects subtend smaller visual angles than near objects, grain, size, and motion parallax.
A more stable food supply
