@futurebird @the5thColumnist @Urban_Hermit Why do you say this versus "most likely to be statistically correct"?

Regardless, that doesn't mean it's the right answer nor the right answer for the person asking it.

@datarama @futurebird @alessandro @talya
Could you give an example, please?
I have to confess that I'm not sure if I've ever thought about how reptiles think.

@Gorfram @futurebird @alessandro @talya I just answered myself with a collection of things Copilot 95 would have gotten wrong.

The short version is that reptiles are neither particularly stupid, particularly asocial or particularly emotionless. In the 60s it was commonly believed that there was a primitive "reptile complex" in the brain that only covered the most basic instinct-driven behaviour and processing of simple stimuli. This is *still* part of popular understanding; it's what people mean when they talk about "the lizard brain". The concept got popularized by (rest his soul) Carl Sagan in his book "The Dragons of Eden" from 1977.

But it turns out an actual lizard brain is nothing like that primitive extended-brainstem structure he described! Lizards have a limbic system just like mammals (and they *definitely* experience emotion), some even practice parental care (in monkeytail skinks for up to a year), live in stable family groups and adopt orphans, and some others form lifelong monogamous pairs (shingleback skinks are famous for this; they even have a range of behaviour that is hard to explain as anything other than a kind of grief when a partner dies).

It used to be commonly accepted that reptiles were incapable of learning novel problem-solving behaviour, because they don't have a neocortex (which is what mammals use to do that). But it turns out that the dorsal ventricular ridge (which reptiles share with birds) plays a similar role to the mammalian neocortex, and packs an enormous amount of neurons into a comparatively tiny volume. Until 1997, we thought it was just a ganglion that handled motor control.

Little anoles with brains the size of pinheads do better on the worm-in-a-lid puzzle than most songbirds and can even learn by looking at other anoles. Monitor lizards can count to 6, tortoises can navigate mazes using something that resembles depth-first-search, crocodilians can put twigs and other items on their heads to use as lures for birds - even adapting which kinds of material they use according to which birds are currently building nests. Many can differentiate individual conspecifics *and* tell the difference between individual humans.

@Gorfram @futurebird @alessandro @talya Oh - also, it turns out that many species of lizard have REM sleep and corresponding brainwave patterns. This means they almost certainly dream - something that was believed to only occur in mammals and birds until ... 2016 (where it was experimentally confirmed in bearded dragons)! That's about the same time Google started developing the very first Transformer-based LLM, in fact (the paper that introduced them came out in 2017).

This threw a lot of things we thought we knew out of whack. We *used* to think REM sleep was something specific to endotherms, and there were a lot of proposed explanations about why. It seemed like it'd have to be an evolutionarily recent adaptation. Perhaps something to do with the higher metabolism of endotherms? Perhaps only endotherms supplied enough energy to the brain during sleep for dreams to occur? All of those explanations made sense and seemed perfectly plausible, but they were also all wrong. Now we don't even know if some ancestral amniote whose descendants would branch off into distinct reptile and mammal lineages was dreaming when it slept some 320 million years ago, or if REM sleep evolved separately in the two lineages.

So there's not really any way Copilot 95 could have gotten this one right.

(...so why should I trust 2025's ChatGPT or Gemini to get it right about, say, amphibians? We haven't seen any evidence of REM sleep in them - but in 2015, we hadn't seen it in reptiles yet either. And just a couple years ago, we found something resembling REM sleep in some species of *spiders*, of all animals! Was some pre-Cambrian proto-animal dreaming too? Until aforementioned spider discovery we thought it'd be such an odd thing to evolve separately that we figured early amniotes "invented" REM sleep; now that's thrown into doubt as well.)

@datarama @futurebird @alessandro @talya
Now I'm wondering what lizards & spiders dream about (I'm guessing flies figure pretty heavily).

So many things in science were right until they were wrong. I remember being taught that the earth's crust rested on a generally quiescent layer of molten lava, which occasionally broke through at weak spots in the form of erupting volcanoes (plate tectonics was known in academic circles by then, but hadn't made it as far as our 1960's-era 4th-grade earth science textbooks).

@Gorfram @datarama @alessandro @talya

Ants and bees probably dream too.

I suspect they would review the things they learned about the space and resources around their nest, making memories of the locations of things more permanent.

This is on the assumption that a purpose of dreaming is to refine and organize memories and things learned during the day.

@Gorfram @datarama @alessandro @talya

Ants and bees probably dream too.

I suspect they would review the things they learned about the space and resources around their nest, making memories of the locations of things more permanent.

This is on the assumption that a purpose of dreaming is to refine and organize memories and things learned during the day.

@futurebird @Gorfram @datarama @alessandro @talya it's honestly kind of poetic that humanity keeps having this scientific uncertainty about whether dreaming serves a purpose