Ancient wisdom tells us that biology is the science of exception.

An ancient wisdom tells us that biology is the science of exceptions. The hemoglobin protein binds oxygen molecules with iron atoms at its center, carrying oxygen into the bloodstream of animals; except when it doesn't! In animals such as octopus and horseshoe crab, hemosyanins carry oxygen and bind the molecule to copper, not iron, making their blood appear blue, not red. Draw any generalization about life on Earth, and from the back of the room, exceptions will appear to greet you. But few biological assumptions dare to say that there are exceptions, the most important of which is the general common regression of one last ancestor, the one that evolutionary biologists tell us you will not find a respected scientist trying to question, but in fact, we have found more than one! – Paul Nelson, philosopher of biology (acting) — Source: Published on Facebook's "Braheen Center" page https://www.facebook.com/braheen.org/posts/pfbid0m4U5KNya3g4HwQNZMr5viY3bPLLiiGJN7HULJwge8eBgXGfWUQ5yP5to1redJ64gl