Do you know the main points of the theory of natural selection?
Did you know that Huizilopochtli was dressed with hummingbird feathers on his head?
Earth and Space Science Concept of the Day
Do you know what this word or phrase means?
Magnetic polarity reversal
xMagnetic polarity reversal : A magnetic polarity reversal is a change of the earth's magnetic field to the opposite polarity. This has occurred at irregular intervals during geologic time.
Current observational tools cannot account for roughly half of the heat that is believed to have built up on Earth in recent years, according to a "Perspectives" article in this week's issue of the journal...Read more