Is Evolution Observable?

[Duke Guilmon]

But humans are apes.

Yes, but that could only be definitively and unambiguously said under a new overarching system of classification of organism developed in the late 20th century.

Prior to that it was recognized humans and apes shared a recent ancestor, but whether humans themselves ought to be considered apes remained an open question, without a universally accepted definition of "ape" to adjudicate the answer.

---

So I guess he should have said it. We know now we are apes but did Darwin ever say that humans were apes?

Whether we are apes depends on how "apes" are defined. You'd be surprised how inexact an art animal group definition and classification had been until late 20th century.

We had a reasonably accurate picture of how different animals such as chimps and men might have been related long before we developed a theoretical framework for rigorously classifying different organisms based on ancestry. Prior to this classifications were based on comparative anatomy rather than ancestry, and it was largely subjective what anatomically distinctive traits were important enough to give an group of organisms a separate grouping of its own. Prior to modern cladistic classification, the combination of bipedalism, tool use, and large brains were considered by many to enough grounds to put hominids into a separate group from apes. In this system, hominids and apes were sister groups sharing an common ancestor. But hominids were not apes.

Darwin would have been familiar with classification by comparative anatomy, but would not have known cladistics. So he would have know calling humans apes would not only be controversial, it would not have received universal backing of all those who otherwise would agree with him on common human and ape ancestry.

This is true. I only say we are apes because animals don't grow out of their evolutionary ancestory. Like we are still chordates and vertebrates and tetrapods. So you can say we are apes or just a subset.