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22 inventions that changed the world
From the wheel 5,500 years ago to the birth control pill, these 20 inventions had huge ramifications and have helped humans shape the world around us.
Body parts grown in the lab
In recent years, scientists have successfully grown a range of miniature organs and human body parts in the lab.
12 strange reasons humans haven't found alien life yet
Scientists have been searching for evidence of extraterrestrial life for decades. So, where are all the aliens? Here are 12 intriguing theories ...
From 'Lucy' to the 'Hobbits': The most famous fossils of human relatives
Countdown Lucy may be the best-known prehuman fossil in the world. But other famous fossils have given us important insight into our evolutionary history.
7 centuries-old suits of battle armor from around the world
Countdown From Roman "fish scale" armor to Japanese samurai suits, these examples of battle armor were designed to protect and impress.
The 9 most massive numbers in existence
From the humble trillion to Graham's number, here are some of the most massive numbers ever conceived by humans.
32 physics experiments that changed the world
From the discovery of gravity to the first mission to defend Earth from an asteroid, here are the most important physics experiments that changed the world.
32 things on Mars that look like they shouldn't be there
The more scientists study the Red Planet, the more they find unusual objects and patterns scattered across Mars' surface. Here are some of the most baffling.
