So I built a stegosaurus model kit, which included some factoids in the instructions. One of these factoids was that stegosaurs are not believed to have had a secondary brain in the hips to help them control their rear half after all. That was wild to me, since the whole stegosaurs and sauropods with their tiny heads needing a secondary brain for their huge bodies was commonly accepted back when I was a kid. So I looked it up, and indeed, the current hypothesis is that the cavity that the second brain was thought to occupy is used for a thing called a glycogen body. But what exactly does a glycogen body do? We’ll get back to you on that, apparently.
I can anecdotally confirm as a “dinosaur kid” of the 80s, that this was a common tidbit in children’s books of the era.
I’m pretty sure I had a VHS with Fred Savage where they ran through it as well.
The explanation was that the response time if a Brontosaurus got its tail messed with (an anvil dropped on it) was problematicly slow if the nervous system had to send the message such a great distance to the “head brain” and then have the reaction message all the way back. Basically they’d be living with massive lag IRL.
Can’t say I’m surprised that science is backing off the certainty on that. Those same books were also full of “look at all the goofy things previous generations of paleontologists thought”
Yeah, I also remember the whole ’ second brain in the tail’ thing being a hypothesis back then
Dinosaurs! (1987)
Link to relevant scene (starts ~17:05)
Wow! The small brain in my butt responsible for nostalgia was blown!
If a Brontosaurus needed to react to an anvil being dropped on its tail then I have more important questions.
Acme anvil, acme time machine… The knowledge that birds evolved from dinosaurs…
The answer is so obvious I’m glad you didn’t debase either of us by asking the question
People then were smoking cigarettes so who knows
Laughing that kids didn’t get taught this in the day! It was “common knowledge” when I was a child. And I had an excellent science teacher. That woman taught me empiricism and how to form an hypothesis and test it. We simply didn’t know in the 70s and 80s!
Doesn’t that already happen in the spine?
That’s just more autonomic system reaction, NOT a “second brain”. Anyone saying such is and always has been an idiot misinterpreting what the autonomic system is. Reacting to stimulus is a far cry from a “brain”.
It’s exactly how the “fencing response” exists. It is NOT a brain reacting, but the nervous system itself making a desperate gambit on protection. Just like how someone will generally pull their hand away from something hot before they think, “damn that’s hot!”, the nervous system itself can and does react to things. That has NEVER meant “other brain”.
Note that I HAVE heard fool hacks try to claim the brain extends in to the spinal chord for these reasons, but they are similarly fools misinterpreting the actual science.
I’m just telling you what was in children’s dinosaur books from the 80s, based on your response of never having heard of it.
What the gap between children’s books and scientific consensus at the time was, couldn’t tell you.
I think this sits in the realm of history more than science. “What were people writing at the time?”
Fair enough that it could’ve been basically rumor in writing, but I’ve been exposed to a ton of the 80s and still never heard it.
Maybe a good sign that such silly beliefs were so rapidly abandoned.