People living in equatorial countries have a darker skin tone than others. what would be the reason for this change in skin tone

The distribution of related animals and plants across the world

What characteristic make legumes a good food source for food insecure populations

When new rock is added to an oceanic ridge, the magnetized strips on either side of the ridge are evidence of sea-floor spreading. this is because the rocks on the two sides of the ridge o are equal in width and in polarity are polar opposites oare magnetized vary in width but are equal in polarity