This year, our Museum foyer has featured an exhibit of unusual fossils in the New Acquisitions Case. This exhibit, Finding the Impossible: Unique Tropical Fossils from William Lake, Manitoba, included a video “slide show” that documented the expeditions during which we collected these fossils. My colleague remarked to me the other day that this slide show should be shared widely using the Museum blog; this post, and some subsequent ones, will do just that!
The exhibit panel’s text gives a brief outline of the project:
How does an animal become a fossil? How is a fossil jellyfish even possible? Only bones, teeth and shells are commonly fossilized, while soft tissues rot or are eaten by scavengers. Jellyfish and other soft tissue fossils are not quite impossible, but they are very rare, preserved only in unusual environments.
The fossils at William Lake are 445 million years old, dating from the Ordovician Period of geological time. They represent creatures that lived along a tropical shore when Manitoba straddled the equator. The remarkable preservation resulted from low oxygen and high salt levels in lagoons.
These specimens were collected by a Manitoba Museum research team, collaborating with scientists from the Royal Ontario Museum and University of Saskatchewan, and students from the University of Manitoba. During fieldwork in central Manitoba in 2000, we discovered the first of these soft-tissue fossils. Through hard on-the-ground work, we located the site. We travelled there numerous times, excavating thin dolostone (limestone) layers to extract the specimens displayed here.
The first part of the accompanying slide show provided some background on Manitoba limestones, and shared the experience of travel to the Grand Rapids Uplands of northern Manitoba. I hope you will enjoy these images (please click on any image if you wish to see it full size).
To be continued . . . next time I will talk about the fossil collecting process, with many graphic images of dusty and hot, or cold and wet paleontologists!