eli5: How did stegosaurus’ plates potentially regulate their body temperature?


How would this have worked? Are they any animals today that do something similar?

In: 1

Heat carried in the blood is brought to the plates, whereby they’re dispersed and brought closer to the skins surface so that ambient temperature and wind more easily carries out.

It’s similar to how one’s ears get cold faster than the rest of the body

Basically worked like big radiators. Blood flows through the vessels in the plates which are close to the surface of the skin, breeze cools the blood, blood flows back in the body cooling the rest of the dinosaur down.

Or not, I’m super high and this just made sense.

An elephant uses its ears to help maintain body temperature. When it gets too hot, blood flow to the ears increase and the elephant sticks them out away from its body, exposing more surface area to the air. The blood coursing through the thin membranes of the ears effectively transfers heat to the air returning a bit cooler into the rest of the body. The elephant can also flap its ears to increase this heat exchange or pull its ears tight to decrease it. Lots of animals have similar regulatory mechanisms – birds spread their wings and flap them slightly to increase heat dissipation, lizards raise spines on their backs exposing a membrane to the air, etc. Stegosaurus plates may have served a similar function.

While that was the leading theory at one time, it has been seriously questioned. Nowadays the leading theory is that they were for display, either to attract mates, intimidate rivals, or deter predators.

Regardless, the thermoregulation theory goes that the plates would have been full of blood vessels, and the greatly increased surface area would have acted kind of like a heat sink, cooling the animal. Alternatively, the animal could have used the plates to catch more sunlight and thus warm its blood quicker.

One knock against this theory is that most related stegosaurs like Kentrosaurus had long pointy spikes, not big flat plates, which would not have been nearly as effective for thermoregulation.

There are animals today that do something similar: elephants. Their ears are very thin and full of blood vessels which, combined with flapping of the ears, gives a large surface area to dissipate excess heat.

The same way that modern animals can with their horns. There’s chambers in there that they can pump blood into and allow it to radiate heat away.