amnhnyc:It’s our favorite time of year—Cephalopod Week!—the annual celebration of all things tentacl
amnhnyc:It’s our favorite time of year—Cephalopod Week!—the annual celebration of all things tentacled. We’re teaming up with @sciencefriday to talk about cephalopods, and celebrate these amazing, adaptive, and sometimes creepy creatures.Today’s Fossil Friday is a look at the diversity of some extinct cephalopods, ammonites. For some people, the Mesozoic era is the age of dinosaurs, but it was also the age of ammonites. When you think of an ammonite, you probably think of a spiral-shelled sea creature. But in fact, this was just one of the many shapes that ammonites took. Scaphites start with a closely-coiled shell and culminate in a hook. Baculites departed from the planispiral coil altogether, and formed a straight shell. Nipponites have meandering whorls, and turrilitids begin to look a little like snail shells. There are probably altogether about 30 different shapes of, of ammonites.Evolutionary biologists at the turn of the 19th century figured that these shapes must have indicated something was very wrong with the ammonites, with the gene pool of ammonites, and this presaged their ultimate extinction, but nothing could be farther from the truth.Learn more about this amazing array in a new video and find much more on the @cephalopodweek blog! -- source link
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