Human Activity Has Permanently Altered Earth, for Better or Worse (Mostly Worse)

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Modern humans have roamed Earth for just a few hundred thousand years. In the grand scheme of things, that's a very short period. But in that time, we’ve triggered mass extinctions of plants and animals, polluted the planet, and developed nuclear weapons—and our legacy will linger in both nature and the geologic record long after historical records have been lost, according to Ted-ED’s video below.

Modern humans have altered the Earth’s landscape and atmosphere so profoundly that some scientists say we’ve ushered in a new epoch called the Anthropocene, or "new age of humankind," from anthropo (human) and cene (new). Before this, we were living in the Holocene (meaning “entirely recent”), which began around 11,700 years ago and faded sometime around 1950.

The 1950s ushered in both the plastics revolution and the atomic age, both of which permanently introduced chemicals into Earth’s fossil record. Meanwhile, humans have also shaped long-term plant and animal evolution with agriculture, fishing, and hunting. In short, our actions have long-term consequences, even if the human species ends up being a blip on the geologic time scale. Remember that the next time you drink from a plastic bottle, or see a cloud of smoke billowing through the sky.

Why Is Pee Yellow?

Chloe Effron
Chloe Effron

WHY? is our attempt to answer all the questions every little kid asks. Do you have a question? Send it to why@mentalfloss.com.

Your body is kind of like a house. You bring things into your body by eating, drinking, and breathing. But just like the things we bring home to real houses, we don’t need every part of what we take in. So there are leftovers, or garbage. And if you let garbage sit around in your house or your body for too long, it gets gross and can make you sick. Your body takes out the garbage by peeing and pooping. These two things are part of your body’s excretory system (ECKS-krih-tore-eee SISS-tem), which is just a fancy way of saying “trash removal.” If your body is healthy, when you look in the toilet you should see brown poop and yellow pee.

Clear, light yellow pee is a sign that your excretory system and the rest of your body are working right. If your pee, or urine (YER-inn), is not see-through, that might mean you are sick. Dark yellow urine usually means that you aren’t drinking enough water. On the other hand, really pale or colorless pee can mean you might be drinking too much water! 

Your blood is filtered through two small organs called kidneys (KID-knees). Remember the garbage we talked about earlier? The chemicals called toxins (TOCK-sins) are like garbage in your blood. Your kidneys act like a net, catching the toxins and other leftovers and turning them into pee.

One part of your blood is called hemoglobin (HEE-moh-gloh-bin). This is what makes your blood red. Hemoglobin goes through a lot of changes as it passes through your body. When it reaches your kidneys, it turns yellow thanks to a chemical called urobilin (yer-ah-BY-lin). Urobilin is kind of like food coloring. The more water you add, the lighter it will be. That's why, if you see dark yellow pee in the toilet, it's time to ask your mom or dad for a cup of water. 

To learn more about pee, check out this article from Kids Health. 

Flashing Status Symbols Won’t Impress New Friends—and May Even Backfire

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iStock

Trying to keep up with the Joneses isn’t a very effective way of making friends. As The Outline reports, a recent study in the journal Social Psychological and Personality Science suggests that flashing status symbols makes people less likely to want to be your friend.

While some may feel like sporting a luxury watch or designer clothes will draw people toward them, it actually does the opposite, making you a less attractive potential friend, according to a trio of researchers from Michigan, Singapore, and Israel. Over the course of six different experiments, the researchers found that study participants tended to think that high-status markers like fancy cars would help them make new friends. The trend stayed true across both participants recruited using Amazon Mechanical Turk and upscale shoppers stopped for a survey in a high-income suburb.

People thought that showing up to an outdoor wedding in a luxury car or going out to a downtown bar wearing a fancy brand-name watch would lead people to be more attracted to them as potential friends, compared to someone driving a basic car or wearing a generic watch. Yet participants also rated themselves as being more willing to befriend someone with generic clothes and cars than someone who flashed designer goods.

The paradox makes a little more sense if you go back to the idea of “keeping up” with our neighbors. People want to look high status in comparison to others. They don’t want to hang out with people who are flashing around luxury goods—they want to be the flashier ones.

[h/t The Outline]

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