Genes may explain why some people love to hug

Twins show that genes play a significant role in how affectionate women are, but not guys. Plus, tips for how huggers can get through social distancing.

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Tags: gender genes twins touch featured society-and-culture social-lives

Multiple births are more common but face disadvantages

Families with multiple births face disadvantages "at every point of care in our healthcare system," a report finds.

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Tags: twins babies families health-and-medicine premature-babies

Twin astronauts show how mitochondria handle space

Astronaut Scott Kelly spent 340 days in space. His twin brother, astronaut Mark Kelly, stayed on Earth. Here's how their mitochondria compare.

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Tags: space mitochondria twins astronauts muscles featured health-and-medicine microgravity siblings