What’s the significance of a human tailbone? Allow Craig Savage to blow your mind with evidence for evolution backed by evolutionary theorist Charles Darwin.

Evolution occurs over millions of years, so how do new species emerge? Time is only one factor— the second factor is reproductive isolation.

Darwin combined truths of geology, economics, and biology to form his theory of natural selection. But did you know he wasn’t the first to consider evolution?

Now that you know what the Hardy-Weinberg principle is, learn how violations of the principle lead to genetic changes within a specific population.

Do you know how genetic variation takes place? Learn how the genetic material of an entire species changes (hint: it happens in populations, not individuals).

Natural selection explains how evolution occurs, but it can also explain why certain organisms (like sharks and crocodiles) haven’t changed in millennia.

Where and how did life on earth originate? Learn about the hypothesis of chemical evolution - in which organic compounds formed from the primordial sea.

When similar waves meet they interfere, meaning they affect each other. In this physics lesson, learn about constructive and destructive interference.

Electromagnetic waves carry energy, making them essential in daily life. In this physics lesson, learn the properties of waves, and how to calculate wave speed!

The waves of the electromagnetic spectrum span quite a range! In this basic physics lesson, review the electromagnetic spectrum and its properties.