NEWS FLASH: Tigers Not Part of Early Human Development

 I’ve being going through the back-catalogue of Tales from the Rabbit Hole, an interesting approach to conspiracy theories and conspiracy theorists.  In the most recent that I’ve listened to, Episode 32, Mick West spoke with the Skeptic of (should be “in”) the North.

 

During their discussion, at about 24:45, there was mention of Michael Shermer talking about the evolutionary benefit of making a Type 1 error (or a false positive) when the data is ambiguous and the example given was of one of our ancestors hearing a rustle in the grass.  The cost of making a Type 1 error and assuming a tiger (when there isn’t one) is minimal, but the cost of making a Type 2 error and assuming there is no tiger (when there is one) could easily be massive.

 

Michael Shermer did in fact raise this as an example, in a blog post called Patternicity: “Better to flee a thousand imagined tigers than be taken unawares by one real one”.  What Shermer isn’t suggesting, however, is that there was an evolutionary pressure placed, by tigers, on humans to make Type 1 errors in response to ambiguous data.

 

Peter Watts did though:

 

Fifty thousand years ago there were these three guys spread out across the plain and they each heard something rustling in the grass. The first one thought it was a tiger, and he ran like hell, and it was a tiger but the guy got away. The second one thought the rustling was a tiger and he ran like hell, but it was only the wind and his friends all laughed at him for being such a chickenshit. But the third guy thought it was only the wind, so he shrugged it off and the tiger had him for dinner. And the same thing happened a million times across ten thousand generations - and after a while everyone was seeing tigers in the grass even when there weren’t any tigers, because even chickenshits have more kids than corpses do.

 

It’s bad enough when apologists use tigers attacking our ancestors as an example when trying to prove that evolution doesn’t exist, but when atheists and skeptics start talking about our ancestors on the African plain being attacked by tigers, it’s a problem.

 

There are two problems really.  First and foremost, tigers have never lived in the wild in Africa (although there might now be feral tigers, that is tigers who have escaped from zoos after being transported to Africa by humans).  If we want to pretend that humans have been shaped into regular Type 1 error makers, by tigers, then we have two options.  First, this applies solely to people with ancestors who lived in the natural range of tigers – with the rest of us not being so inclined. Or, second, our understanding of where we evolved is wrong and we somehow evolved within the natural range of tigers despite the evidence that we evolved into hominid form on the African savannah.

 

The other problem is that if we, as evolving hominids, had not already developed the handy skill of overestimating the level of risk to our lives, we would not have been in the position to evolve into Homo sapiens.  Not that tigers would have eaten us, but lions or wild dogs would have, or any number of dangerous African creatures would have killed us without even bothering to eat us.

 

Making Type 1 errors and treating something benign as a possible threat is not unique to humans: 

I am quite confident that this cat is not going through a calm assessment of the potential for risk associated with the cucumber.  It’s just an instinct to run away from something that looks vaguely like it could be a snake.  Horses are similar, with them freaking out if they see a hose (where they aren’t expecting to see one).  Admittedly horses freak out about a lot of things: plastic bags, people wearing hats, trees, the wind, sand and so on.  Even fish seem to be in the Type 1 error club.  And coral.

 

The point is that this characteristic of being overly cautious about ambiguous data is not a human thing, it’s a characteristic of all higher order animals.  Maybe, it could be argued, even lower order animals are willing (on a metaphorical level) to make the occasional error in order to increase their chance of survival.  We as humans have not developed it, we have just retained it.

 

The idiocy that is involved in thinking that humans cleverly developed this overweening caution due to their interaction with tigers on the African plain and the arrogance to think that it was only humans who did so … both are, sadly, entirely human.