November 24

New Theory of Life Published

On this day in 1859, Charles Darwin published what would become his most famous work: On the Origin of Species by Natural Selection. This important book explains Darwin's ideas about changes in species over time.

In the book, Darwin explains that organisms of a single species differ from each other. Some of these differences can give some members of the species a "selective advantage" over others. This means that these organisms would have more offspring than the others. Their offspring would also have the difference. Over time, the number of organisms without the difference would be smaller and smaller. Eventually, all members of the species would have the difference, so the species as a whole would be changed.