Monday, January 21, 2008

Toy Trilobites

Recently, my girlfriend brought me a great toy trilobite from the Royal Ontario Museum. It came as part of a collection of Burgess Shale fauna replicas, based on research carried out by the museum's Paleontology Department in an effort to gain greater understanding of the creatures of the Cambrian ocean. The Burgess Shale is located in the mountains of British Columbia, and contains some of the best preserved Cambrian fossils in the world, prized for their incredible detail. They show remarkable preservation of even soft tissue, making them extremely valuable. We are able to see many structures that are normally destroyed before fossilization, including the legs, gills and antennae of the trilobite Olenoides serratus (below).

Also include are Wiwaxia; a sort of armored slug, Pikaia; an early chordate, Laggania; kind of a big, nasty sea-monkey, and Opabinia, a crazy, five-eyed creature with a mobile proboscis at the end of which is its presumed mouth. These creatures are just a small sample of the life from that ancient time of incredible biodiversity.

Monday, January 14, 2008

Mistreated Trilobite

A poor trilobite is harassed by teenagers in this video,
clearly showing that some of us are a long way away from
true trilobite appreciation.... Kids these days!!!

Sunday, January 6, 2008

The Strangest Trilobites

Ceratarges, sculpted by Andrew Scott

When people think about trilobites, if they think about them at all, the mind will often conjure up an image of something half-way between a pill bug and a horseshoe crab. Generally speaking, many trilobites conform to this conceptualization, but, though trilobites usually adhere to this simple shape, there are some that are so sharply deviant as to seem utterly alien. This begins an examination of some of the most bizarre, and most intriguing trilobites ever to have been discovered. Their strange shapes are often suggestive of a discernible function of their once-living selves, but sometimes they inscrutably defy a simple explanation, and we are left with a lasting enigma.

Walliserops Trifurcatus

Walliserops trifurcatus, photo by Peter Cameron

Did Walliserops trifurcatus use its elongated, fork-like frontal projection to dig for soft bodied prey on the sandy sea floor? It would seem possible, yet we are unable to be sure without any direct evidence. Could the same structure have been a defensive adaptation, or have been brandished in ritual combat to determine sexual preference or to establish territory? Without the ability to directly observe their behavior, or to determine which trilobites were male or female, we can never know. Perhaps this trilobite's trident performed a combination of these functions, but maybe it was used for some unknown purpose.


Dicranurus monstrosus, photo by Peter Cameron

The twisted, horn-like projections on the cephalon of the aptly named Dicranurus monstrosus add to this trilobite's monstrous character. Coupled with the spiny extensions that fringe this trilobite's body, they readily suggest that this creature would have been a difficult meal to enjoy without injury. In the Devonian strata, fossils of suspected trilobite predators like ammonites and fish are also found abundantly, which would corroborate speculation about the structures' defensive purpose. But, were these spines dislodged during an attack, to be regenerated with successive molts? Were they strong enough to remain attached while repelling predators? Were they meant to cause internal injury as a warning against eating others of that species? Were they poisonous? Can we know the answers to these questions? The strangest trilobites silently defy our inquisition.