Let’s dispense with the obvious first:  this deeply dispiriting exchange was neither a debate nor a conversation nor even a policy discussion.  It was a shouting match, and the American people lost out.  This event was the least edifying, most unpleasant political evening I’ve ever spent.

Yes, President Trump interrupted and talked over Vice-President Biden more than the reverse.  And yes, Biden called Trump a “clown,” and told him to “shut up.” Yes, Trump went after Biden’s son several times, presumably trying to goad the Vice-President into losing his temper.  Yes, Biden managed to keep his temper.  And yes, Chris Wallace lost control of the evening and was unable to do his job of moderation effectively.

Can the study of body language tell us anything useful beyond the obvious about the evening?  Surprisingly, perhaps, a couple of things.  Here are my takeaways, besides noting that the first presidential debate was neither presidential nor a debate.

1. Both candidates were aging alpha males on hyper-alert status. Both Trump and Biden were standing at full height, and regularly during the evening, as they began to tire, and sag slightly, they pulled themselves back up to full height again.  They were both holding themselves rigidly, prepared for a fight.  The effect was as if we had two old silverbacks competing for the domination of the troop.

2. Trump’s body language was markedly different from his debate with Hillary Clinton. During his debate with Clinton, as was widely noted at the time, Trump stalked Clinton around the stage and engaged in some very expansive gesturing with both arms and with one hand, at various times.  Here, he stayed behind the podium and was much more limited in his gesturing.

3. Trump’s limited gesturing was often with just one hand; normal conversational gesturing usually involves both hands. We typically gesture with one hand when we are angry, dismissive, or passionate.

4. Biden’s gesturing, especially when he turned to the camera, was more balanced.  Biden reached toward the camera (and the American people) with both hands.  Thus his attempt to connect with the television audience felt more reasonable and emotionally controlled.  Mostly, Trump did not attempt to connect directly with the television audience in this way per se.

5. During the Clinton-Trump debate, Trump displayed constant anger; for his debate with Biden, his expression was typically one of contempt or dismissal. Trump’s facial expression was more restrained than in the previous debate.  For his part, Biden smiled far more often and looked down or away more often.  Typically, this meant he was taking himself out of the fray and waiting for Trump to finish.

6. Both candidates’ pitch was elevated, showing stress and the result of a “fight or flight (or freeze)” response. Adrenaline can cause our voices to rise in both pitch and volume and both men displayed this sort of tension. 

So there you have it.  Body language doesn’t always reveal what we expect; in this case it did reveal that – whatever else was going on – Trump took Biden much more seriously than he did Clinton four years ago.