Fossil Record of Cephalopods

Fossil Record of Cephalopods - speculate that the...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Fossil Record of Cephalopods During the Jurassic, the cephalopods once again produced a new coiled, chambered form, the ammonites, shown in Figure 13 and 14. Suture patterns of these forms were even more elaborate than those found in the Triassic ceratites. The belemnites were straight-shelled cephalopods with elaborate suture patterns. Both ammonites and belemnites survived the Jurassic extinctions and flourished during the Cretaceous period. Ammonites continued their dominance, as did their relatives the straight-shelled belemnites. Modern teleost fish appeared during the Cretaceous and may have competed for the same prey as the ammonites. The teleost fish were apparently stronger and swifter swimmers than the fish of the Jurassic. Some paleontologists
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Background image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: speculate that the extinction of ichthyosaurs during the Cretaceous may have been hastened by the rise of these new faster fish that would have been difficult for the ichthyosaurs to catch and eat. Baculites , a genus of straight-shelled cephalopods, was particularly abundant in the Cretaceous seas. Note the elaborate suture patterns in the fossil specimen below. Common fossils in the Cretaceous rocks, the cephalopods were major victims (along with the gastropod group the rudistids) of the terminal Cretaceous extinction event. Squid, octopus, and the chambered nautilus are the remnants of this once flourishing group of molluscs....
View Full Document

Page1 / 3

Fossil Record of Cephalopods - speculate that the...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online