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  • It's AumSum Time

  • Why do we have different skin colors?

  • It is because of a pigment called melanin and ultraviolet radiation of the sun.

  • Confused?

  • Obviously.

  • Alright.

  • I'll explain.

  • Millions of years ago, people living near equator received a lot of sunlight and ultraviolet radiation.

  • Now, ultraviolet radiation is actually absorbed by our skin to produce Vitamin D.

  • But excess radiation can damage our skin cells.

  • Hence, the skin of these people produced more melanin to block the excess ultraviolet radiation.

  • Thus, over time.

  • These people and their succeeding generations adapted to have a higher level of melanin in their skin.

  • Making their skin darker.

  • However, people living away from equator received less sunlight and less ultraviolet radiation.

  • Hence, in order to absorb sufficient ultraviolet radiation and produce the essential Vitamin D.

  • These people and their following generations adapted to have a lower level of melanin.

  • Thus making their skin lighter.

It's AumSum Time

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B2 中高級 美國腔

為什麼我們有不同的膚色?| 奧琛時間 (Why do we have different skin colors? | It's AumSum Time)

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    wwzz1207 發佈於 2021 年 01 月 14 日
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