Wednesday, July 18, 2012

Just a Little Ammonite

Ammonite by megan_n_smith_99
Ammonite, a photo by megan_n_smith_99 on Flickr.

It's so sad that ammonites are extinct. They had such an interesting structure. Though not really surprising since 98+% of all species that have ever existed are now extinct. You think it could not happen to us? Well, ask Geological time.

The closest living relatives to the ammonites are cephalopods - squid, octopuses* and cuttlefish. They are less closely related to nautiluses - though they do resemble them.

Here is a little tidbit about the derivation of the name, from Wikipedia:

"The name ammonite, from which the scientific term is derived, was inspired by the spiral shape of their fossilized shells, which somewhat resemble tightly coiled rams' horns. Pliny the Elder (d. 79 AD. near Pompeii) called fossils of these animals ammonis cornua ("horns of Ammon") because the Egyptian god Ammon (Amun) was typically depicted wearing ram's horns.Often the name of an ammonite genus ends in -ceras, which is Greek (κέρας) for "horn"."

The first ammonites appear during the Devonian, about 400 million years ago, and the last species went extinct about 65 million years ago, at the end of the Cretaceous, also called the K-T boundary.

The K-T extinction is the most famous mass extinction, but not the only one, and not even the biggest. The biggest was at the end of the Permian era. I could probably go on and on about mass extinctions, even before I started studying geology and paleontology my freshman english 101 paper was on the K-T mass extinction, I am sure that was a 1st, I think my english teacher enjoyed it as a refreshing change of pace. That's what you get for letting students pick their own essay topics. Maybe I will go on about them a bit later, but I am feeling under-the-weather this week so I leave you with this painting of an ammonite.

*Please don't get me started why the plural of Octopus is not Octopi. It has actually become acceptable via common use but it's just so wrong.

Ammonite
4 x 6"
Watercolor and ink on arches 140 cold press paper
Available on Etsy.

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