compare a nautilus to an octopus; also tell how you can protect the 5 out of 2000 species of nautilus' that...

Question

are left

Answer 1

So, what is a nautilus? And then, what is an octopus? They're both molluscs, and both live in marine (salty sea) environments, but in what ways are they different? How many 'arms' does each have? Do they have protective shells? Do they crawl on the bottom or float around up in the water? What kind of food do they eat? What eats them? These are just some of the questions you could be asking. An internet search might help, or you could try talking to someone at your local zoo, or a museum or aquarium - you might find out a whole lot more that way than you could doing this!

Answer 2

Both the nautilus and the octopus are cephalopod mollusks. They are in different orders, however. The octopus has eight tentacles and no fins. The nautilus is more like a squid, but lives in a coiled shell that it secretes throughout its lifetime, moving to a larger chamber each time it grows larger. There is a tube, called the siphuncle, through which the nautilus can fill the empty chambers with nitrogen gas, making the animal neutrally buoyant. The octopus lives mostly on the ocean floor, rather than in the water column. However, there is one octopus that superficially resembles the nautilus. It is called the "paper nautilus", or argonaut. To protect the species of nautiloids that are left, we must cut down on oceanic pollution in general, and in particular, we must put less carbon dioxide into the atmosphere. The ocean absorbs almost 50% of that carbon dioxide, which leads to formation of carbonic acid and a lowering of pH. The calcium carbonate shells of nautiloids cannot form at lower pH, because the carbonate ion needs pH's of 8 and above to stay in solution.