Pathological specimens by Mike Santino

There are times in the life of some organisms when disease, predators or genetic variation cause a change in growth and structure. When this happens, the specimen is referred to as a pathological. While the cause of the modification is speculative, the result is still bizarre.

Recent non-invasive diagnostic technology developments, such as Magnetic Resonance Imaging (MRI), applied to paleontology have revealed precise growth modifications in pathological specimens.

Below are some high resolution images of pathological Cephalopod specimens.

The first is a Belemnite (Neoclavibelus subclavatus) with possible exterior muscular mantle damage causing the otherwise straight guard to bend and straighten again. This damage is possibly due to a bite from a predator.

The second picture is of Placenticeras species with teeth marks from a bite, possibly a Plesiosaur. Marks of this type are usually in pairs showing both rows of teeth of the jaw. This one shows two, non-parallel single sets of lines. Did this dinosaur have a tooth ache and bite down on one side?

The third picture is of an Erymnoceras coronatum with a lump growth and rib pattern change that may be possibly due to parasitic invasion.

The fourth picture is of a Scaphite species with a row of tubercles (spikes) protruding from the center of the venter (outside edge or belly). Normally tubercles grow is two lateral rows along the sides of the venter on Scaphites.

Finally, the ribs of a Sivajiceras congener? change their normal development and change back again due to undetermined causes.

For some terrific digital imagery research see D. Mietchen, H. Keupp, B. Manz, and F. Volke. Non-invasive diagnostics in fossils – Magnetic Resonance Imaging of pathological belemnites. 2005. www.Bigeosciences.net

Neoclavibelus subclavatus Placenticeras sp. Erymnoceras coronatum Scaphite sp. Sivajiceras congener?