The nautilus is a type of mollusk and is related to squids, octopi, and cuttlefish. Unlike its cousins, though, it lives in a multi-chambered shell. The nautilus’s body occupies one of these chambers. It uses the others for jet propulsion! It can pump or expel seawater from these chambers to swim or dive, adjusting its buoyancy. These “chambers function like the ballast tanks of a submarine. This is the secret to how the nautilus swims” (NOAA, 2023).
“The ancient Greeks saw the chambered nautilus shell as a symbol of perfection. The shell can be described mathematically as a logarithmic spiral” (NOAA, 2023). A logarithmic spiral is when the size of the spiral increases, but the shape of the curve is unaltered. Such curves are also seen in sunflower heads.
There is a fossil record of these creatures that reach back at least 500 years. There are no regulations to protect them, and due to overharvesting to collect their beautiful shells, six species of nautilus are in decline.
Reflection Question:
Are you interested in watching a short animation of the beautifully complex logarithmic spiral? https://www.youtube.com/watch?v=vkDyeW5k1fA
Reference:
What is a nautilus? (n.d.). https://oceanservice.noaa.gov/facts/nautilus.html