Human beings have a contradictory relationship with the sun. People love sunshine; however, if you stay out too long or haven’t taken enough precautions (预防措施), your skin will let you know the angry sunburn. First the heat, then the pain, then the remorse. Were people always this obsessed with sunscreens? The answer is “no”.
With only their feet to carry them, our distant ancestors didn’t move around much during their lives. Their skin adapted to subtle, seasonal changes in sunlight and UV conditions by producing more eumelanin (真黑素) and becoming darker in the summer and then losing some pigment (色素) in the fall and winter when the sun wasn’t so strong. This is not to say that the skin would have been undamaged by today’s standards. We can infer from the effects of sun exposure on modern people that the damage was similar.
As time goes by, people’s way of living changes as well. About 10, 000 years ago, human beings made their living by gathering foods, hunting and fishing. By around 6, 000 BC, many people were spending more time in walled settlements, and more time indoors. By at least 3, 000 BC, a whole industry of sun protection grew up to create equipment of all sorts — hats, tents and clothing — that would protect people from the discomfort and unavoidable darkening of the skin related to lengthy sun exposure. In some places, people even developed protective pastes — early versions of modern sunscreens — to protect their exposed skin.
As people have moved around more and faster over longer distances in recent centuries, and spend more time indoors, their skin hasn’t caught up with their locations and lifestyles. Your levels of eumelanin probably aren’t perfectly adapted to the sun conditions where you live, so they aren’t able to protect you the same way they might have protected your ancient ancestors.
People may love the sun, but we’re not our ancestors. Humanity’s relationship with the sun has changed, and this means changing your behavior to save your skin.
【小题1】What is the relationship between human beings and the sun?| A．It’s harmonious. | B．It’s irrelative. | C．It’s complex. | D．It’s conflicting. |
| A．Ancestors’ skin had more eumelanin. |
| B．Dark skin can protect against sunburn. |
| C．The loss of pigment also means skin damage. |
| D．Moving around is beneficial to increasing eumelanin. |
| A．The level of eumelanin and temperature. |
| B．Changes of the lifestyle and location. |
| C．UV conditions and the amount of sunlight. |
| D．Protection equipment and longer sun exposure. |
| A．Some tips for protecting the skin. | B．Examples of how sunlight affects the skin. |
| C．Risks of lasting exposure to the sun. | D．Benefits of adapting to the environment. |
