How do cats purr?
Cats purr when they feel happy, but no one knows how. When they purr, you don’t even hear their heart beating!
Where did some creatures come from?
Many species don’t have any ancestors. No one knows exactly when amphibians evolved from fish.
Do cows have a magnetic compass?
Scientists studied thousands of grazing cows’ images and discovered a strange pattern. 70% of cows turn their heads to the north or south while eating.
What was the “gelatinous” rain?
An unusual phenomenon occurred in Oakville, Washington, in August 1994. Instead of rain, jelly-like substances fell from the sky.
What is dark matter?
About 27% of the universe is dark matter. It doesn’t emit or interact with electromagnetic radiation, so it’s impossible to detect it.
How many planets are in the solar system?
Since Pluto was excluded as an official planet, it’s believed there are eight planets. The Kuiper belt beyond Pluto consists of icy objects. Scientists discovered thousands of objects in that area that are even bigger than Pluto.
Why are people right-handed and left-handed?
Most humans (70% to 95%) are right-handed, and a minority (5% to 30%) are left-handed. An indeterminate number are ambidextrous.
Why did megafauna become extinct?
Giant animals, known as megafauna, disappeared about 10,000 years ago. Some believe climate change killed the megafauna, but there is no strong evidence. According to another theory, the animals died due to starvation.
Why do we dream?
Some believe that dreams are random images and brain waves. Others consider them subconscious desires, unsolved problems, and experiences.
Why do we have different blood types?
Blood types have different antigens in blood cells. They are signals of antibodies that destroy foreign cells in the body. But scientists have no answer why they are different.
