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It's just like a white desert for as far as you can see. There is absolutely nothing and you come back and it's overwhelming. Between 2016 and 2018 Dr Tim Heitland spent 14 months in antarctica ...

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Like all young mammals, human infants depend on milk for nutrition. Milk is rich in lactose, a disaccharide made from two sugar molecules. Lactose cannot be directly absorbed in the small intestine. T...

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Mutations arise at random in a population. Suppose a mutation arises that causes adults to produce lactase in a population that doesn't have any dairy cows. Adults don't drink milk, so producing the l...

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Human existence is scary and confusing. A few hundred thousand years ago, we became conscious and found ourselves in a strange place. It was filled with other beings. We could eat some; some cou...

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Polymerase chain reaction-- or PCR-- uses repeated cycles of heating and cooling to make many copies of a specific region of DNA. First, the temperature is raised to near boiling, causing the double s...

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So this squid is a nocturnal animal. And so what we've done is we put this poor guy in his water during the day. And he doesn't like it. So he looks kind of uncoordinated, he looks a...

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Humans have existed for millions of years, as part of nature. But then, something changed. And in an incredibly short amount of time.. ..We terraformed this planet and designed it to fit our nee...

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So let's look at what these guys will eat. If I could have the video, please. So this snail has its proboscis stuck out. That's the translucent yellow tube. And you can see, it stings...