Philosopher and secular humanist Christopher diCarlo claims that if humans trace their lineages far enough back in time, they will all have an African origin. He has been spreading his "We Are All African!"¹ message on a cross-Canadian tour. However, the science behind diCarlo's version of history leaves plenty of room for skepticism.

The blob lives. Or at least, it has been reconstructed in a three-dimensional computer model.

An animal wouldn't grow larger than an insect without specialized equipment designed to transport oxygen to and carbon dioxide from cells deep inside its body. Fortunately, thousands of different animal kinds have been outfitted with tiny machines called hemoglobins that directly and specifically interact with individual oxygen molecules, making larger body sizes possible.

Does gravity exist?

Stem cells from adults can be "coaxed" into becoming more specified tissues and used effectively for specific treatments. Stem cells from embryos, however, involve the destruction of a human life and have not yet offered any useful treatments.