Mailbag: Ardipithecus, the documentary

Regarding the “Discovering Ardi” program:

I thought the animation of Ardipithecus walking was kind of wierdly UNhuman like actually. I'd have to go back and look at it again but it seemed kind of li ke a waddler..... NO?

The legs were totally straight; if it had been chimp-like, there would have been a bent-leg stride and more side-to-side.

I think the only thing chimp-like about it was that the toe-off required it to tripod up onto the 1-2 MT/P joints, kind of like a turkey walking. And then there was the arm-swing, which with a 1.5x human length arm looked like Shaggy from Scooby Doo.

And from another reader:

Many people seem to be searching for evidence of exclusive pair bonding among human ancestors in the archaeological record (e.g. Lovejoy's observations in the Ardi program). They are jumping to the wrong conclusion, I think. Exclusive pair bonding tends to create stronger pairs, but a weaker group. Network bonding (numerous partners both ways) tends to produce weaker individual pairs, but a stronger group. An anology from chemistry might be the differences between graphite and diamond caused by the differences in carbon bonds. In a small group, any bonding behavior that creates strong preferences and strong aversions should inevitably tend to create ready fracture lines within the group. Ultimately, this should tend to decrease the long term viability of both the group and the individuals. Conversely, bonds which criss-cross the group tend to make the loss of any one individual less painful and to make both the group and the remaining individuals more resilient. This search for pair exclusive bonding evidence seems to be an unwarranted intrusion of modern culture into scientific work.

I think this is a really good point.

I don’t know how much you know the field, but Lovejoy’s views on pair-bonding are highly ideosyncratic – they mostly bear influence because he is well-known for other work.

The idea of adapting to social networks is much more the wave of the future. It’s not immediately obvious what morphological correlates (if any) we might expect as a consequence of network bonding.