Human populations in low-uv environments tend to have more lightly pigmented skin. one explanation is that the selective pressure for dark skin decreases as uv intensity decreases. at the same time there is selection for lighter skin to absorb more uv radiation, which is needed for vitamin d production. what evidence supports the vitamin d hypothesis for the evolution of lighter skin tones?

Hello. This question is incomplete. The full question is:

"Human populations in low-UV environments tend to have lighter skin tones. One explanation is that the selective pressure for dark skin decreases as UV intensity decreases. At the same time, there is selection for lighter skin to absorb more UV radiation, which is needed for vitamin D production. What evidence supports the vitamin D hypothesis for the evolution of lighter skin tones?

In general, people with lighter skin tend to be at higher risk of vitamin D deficiency.  Red hair and light skin are typical of people of northern European descent.  Some indigenous peoples living at high latitudes have darker skin, but they tend to eat foods rich in vitamin D.  People with lighter skin cannot synthesize enough vitamin D in high-UV environments, such as equatorial Africa."

indigenous peoples living at high latitudes have darker skin, but they eat foods rich in vitamin D

Explanation:

There is scientific evidence that states that more pigmented skins or with potential for pigmentation (through tanning) are evolutionary results of primitive human populations that lived in low UV radiation environments.

This was because the environmental conditions related to the intensity of UV rays, determined that the most pigmented skins would be favored by the lower intensities, in relation to the less pigmented skins, causing a selection pressure. lighter skins, however, absorb more UV radiation, which is necessary for the production of vitamin D.

An argument that provides the basis for this claim is that indigenous people living in high latitudes have darker skin, but eat foods rich in vitamin D, for this reason, they do not need to absorb as much UV radiation to form this protein.

9.9 years

a = p(1 + rt) . . account balance after time t at rate r starting with principal p

3000 = 2500(1 + 0.0202t) . . filling in the given numbers

1.2 = 1 + 0.0202t . . divide by 2500

0.2 = 0.0202t . . . subtract 1

0.2/0.0202 = t ≈ 9.901

it will take about 9.9 years for the account balance to reach $3000.

the eggs of the insects should be the first thing collected at the scene.

false