This is a light hearted article discussing the findings of a paper on the nautilus, and why it only lives in the area that it does. It was a pretty fun read. Thanks for posting it. The bit that...
This is a light hearted article discussing the findings of a paper on the nautilus, and why it only lives in the area that it does. It was a pretty fun read. Thanks for posting it.
The bit that hooked me:
(Years ago, I used to scuba dive in that area. My dive instructor told me that a nautilus never comes above 100 meters depth unless it’s seriously ill or injured. Meanwhile, a recreational diver should never go below 40 meters depth — nitrogen narcosis, oxygen poisoning, the bends, just don’t. “So if you’re diving and you see a nautilus,” he said, “at least one of you is in big trouble.”)
Okay, so: why? Why is the nautilus restricted to this small area, when older armored cephalopods roamed worldwide? Is the nautilus just… worse? An inferior design, or something?
No. Here’s where things get mysterious and interesting. After the asteroid hit, the ammonites all died out. But chambered nautiluses survived, and they thrived! They weren’t as ubiquitous as the ammonites, but for about 30 million years they were found all over the world. Dozens of species, all sorts of different habitats. The “shell, but also tentacles” design was still solid.
But then around 30 million years ago — halfway through the Age of Mammals, give or take — something happened. The nautiloids started disappearing. Fewer species, less diversity. Bit by bit they shrank back into their current small range.
This is a light hearted article discussing the findings of a paper on the nautilus, and why it only lives in the area that it does. It was a pretty fun read. Thanks for posting it.
The bit that hooked me:
I really enjoyed this! A fascinating little bit of something I'd never come across before. Thank you for sharing!