Evolution at the zoo

I just saw this post over at the Axis of Evo blog, and remembered a photo I took of a sign at the Denver Zoo on primate evolution... which included humans.  The photo was taken in early July, 2009 in front of the gorilla exhibit.

Figure 1. The sign.

First, I think it's fantastic that the Denver Zoo isn't being shy, and is trying to educate the public about where our species sits in the tree of life -- especially in relation to the (other) great apes.  I've seen lesser zoos completely devoid of such efforts.

That said, there were some problems with the sign:  It depicted an outdated relationship between humans and other apes, and it looked as though someone was trying to sugar coat those human-to-primate relationships further by including extinct groups that (conveniently?) introduce extra space between humans and the other primates.  In any case, I think the sign needs an update...  Here's a closer look at the bottom panel -- their presentation of the major modern primate lineages plus one extinct group...

Figure 2. The bottom panel from the sign in Figure 1.

I could be wrong here, but last I recall all the evidence suggests this picture (excluding the extinct "ape-men") should look something more like this:

Figure 3.  An edited (or maybe, corrected?) version of the sign above.

Only a few feet away, should any visitor get curious, were nice close looks at Gorillas and Orangutans.  I was able to snap this picture...

Figure 4. Hand of a female gorilla, napping a few feet away from the sign above.

Perhaps not as impressive as the big silver-back, but it does nicely illustrate how some of our human features maybe aren't as exclusively human as some like to think.