Demonstrating that snakes experience emotions

[Malum Argenteum]

Can I disagree?

He doesn't 'demonstrate' that snakes have emotions. He simply postulates his conclusion. He presents a calm snake, and then a skittish one that calms down with time and handling, and assumes the conclusion is apparent. This is the most troubling part of the video, in my opinion. He's preaching to the choir, to use one metaphor; he's begging the question, to point out the formal error in reasoning.

That 'demonstration' doesn't establish anything about internal states, and might be explained much more simply in terms of reduced stress responses. Stress hormone levels such as cortisol/corticosterone modulate "fear" responses, but this doesn't necessarily entail a corresponding mental state since animals such as corals use the same chemicals when "stressed" (and I don't think it is reasonable to suppose that corals have emotions).

He also states that people who responded to his question basically all thought snakes have emotions. That's a public opinion poll, which tells only what people think (or better: what they claim to think) and may or may not reflect reality. Consider those polls about how many people think the earth is 6000 years old, or the like; no fact about geologic history can be inferred from them.

As far as I know, there aren't sufficient structural anatomical homologues in reptile brains that would support emotions in at all the same way that they're supported in animals we're pretty sure have emotions, so again if snakes have 'emotions' that word means something pretty different than we mean in humans. It would be like supposing snakes could fly, even though they don't have wings or any structure that we know assists flying in all the animals we think can fly. Someone might assert that snakes fly by some unknown mechanism such as blowing air out of their cloacas and steering with their tongues, but that would take quite a lot of solid evidence.

Snakes of course respond to pain, and to situations that we categorize as stressful, but even if those experiences involve some sort of conscious state, emotion is something over and above that.

Another hurdle to get over is formulating even a possible evolutionary explanation. It is hard to imagine a case that could be made that there's an adaptive advantage to emotion in animals such as snakes. There are very clear disadvantages that must be outweighed by reproductive benefits. Emotion is both physiologically costly (calories to run the brain structures -- real bad in an animal that has erratic food intake and depends on a low metabolic rate to survive) and has adaptive downsides (pretty much every boneheaded thing humans do that is driven by emotion). Unless there are serious adaptive benefits -- a good example is the social bonding needed to make human and similar animals' reproductive patterns work well -- emotions won't evolve. I don't see any reason to think that emotion would be adaptive in snakes, certainly not adaptive enough to outweigh the costs.

One sort of anecdotal test that I personally use to try to figure out the mental states of animals is to see whether they remember stressful experiences. Mammals (at least cats and sheep, the non-human animals I pay the most attention to; sheep do it more clearly, which is interesting) do. But snakes are different. When I hold a snake down to give it an injection, it freaks out like it is going to either die or kill me. But five seconds after I release it, it is fine. My vet (former, now a zoo vet) pointed out to me some time ago that snakes don't hold grudges over passing offenses, and I think that's true (of course chronic stressors will have much more lasting effects, but that's likely explainable purely physiologically). But emotions of the sort humans are familiar with have connections with memory that make our experiences in this regard very different.

Anyway, just some friendly food for thought. I won't push this, but some might find it useful to consider some problems with the idea.