Iron weighs more after it rusts.
68
The smell of freshly cut grass is actually a plant distress call.
31
Pumice is the only rock that floats on water.
14
Columbia University has developed an artificial tree that passively soaks up carbon dioxide from the air using "leaves" that are 1,000 times more efficient than true leaves that use photosynthesis.
15
Out of all the senses, smell is most closely linked to memory.
146
A coal power station puts 100 times more radiation into the air than a nuclear power plant producing the same amount of energy.
7
Only 12,000 years ago there was a species closely related to modern humans called Homo floresiensis that had been living on an Indonesian Island. They used fire and rather advanced tools, yet were only about 3 feet tall and weighed around 25kg.
15
Kissing actually has the biological purpose of passing on biological information and chemical signals to assess mating possibilities and status.
9