Flipping the Skull

By Dr. Graham Young, Curator Emeritus of Geology and Paleontology

It is exciting and interesting to work with the fossils of large vertebrate creatures, but this is a field with many complexities. During the fossilization of most vertebrates, the bone was replaced by other minerals, which makes the skeletal components both heavier and more brittle than they were during the animal’s life. For those of us working in the “back rooms” of museums, it can be very tricky to move these large, weighty, and fragile fossils as we prepare them, study them, or mount them for exhibit.

A few weeks ago, we had to perform one of the trickiest tasks associated with big vertebrates: flipping a skull. The large pliosaurid plesiosaur that was donated to the Museum by Wayne Buckley had been fully prepared by Wayne, so that the bones are completely removed from bedrock; their weight is supported by mounts or cradles (structures similar to the plaster field jackets). This makes the fossil much easier to exhibit or study, but it means that we have to ensure that we are fully supporting the skull whenever we move it, so that it doesn’t collapse or break. Since this particular specimen is unique and scientifically important, and since it has survived the past 90 million years or so in remarkably good condition, it is imperative that we take extra care!

In late September, we were visited by Dr. Tamaki Sato (Tokyo Gakugei University) and Dr. Xiao-Chun Wu (Canadian Museum of Nature), who spent several days here studying the skeleton for a scientific publication. Before they arrived, Debbie Thompson had been making the final exhibit mount for the plesiosaur; to allow her to do that work, the skull was resting in a temporary support cradle, with its “back” side (the side hidden during exhibit) facing up. We knew that Tamaki and Xiao-Chun would want to thoroughly examine both sides of the skull, and that at the midpoint of the week we would need to flip it so that they could study the “front” side.

Knowing this in advance, Debbie had prepared a second cradle that would fit onto the the side that was currently up, making this support out of wood, plaster, burlap, and other materials. Unfortunately for us, Debbie was on vacation when the visiting scientists were here, so it was left to the rest of us to ensure that the cradle was used as she had intended.

On the Wednesday afternoon, Collections Specialist Janis Klapecki and I went to the room where the plesiosaur is laid out, and with Tamaki and Xiao-Chun we fitted Debbie’s second cradle over the skull. The fit was perfect, so we wrapped sturdy packing straps around the two cradles, then tightened them until there was no give and the wood supports were flexing a bit. This tightness would ensure that the bones would move as little as possible during the flip.

When we were ready, we were joined by several of our curatorial colleagues, who had kindly volunteered their assistance. The skull and cradles were not immensely heavy, but the operation had to be done very steadily and smoothly, so it was best to have two or three people on each end of it. Once we had everything in place, and once we had discussed how we would do it, it only took a couple of moments to actually flip the skull.

By Dr. Graham Young, Curator Emeritus of Geology and Paleontology

Last week was the Museum’s “cleaning week”, during which we were closed to the public so that we could focus on getting our house in order. There was much recycling of paper, moving of old furniture, and scrubbing of walls in many parts of the Museum. Here in the Geology and Paleontology lab, we decided that this was the ideal time to file some of the fossils that had been catalogued in the past few months. Most particularly, we put away several hundred Ordovician age trilobites from the Stony Mountain Formation at Stony Mountain, just north of Winnipeg.

We knew that the Stony Mountain trilobites had been gradually “stacking up”, and volunteer extraordinaire Ed Dobrzanski and I had decided that we would devote some serious time and space to this project when we could. A few months ago the lab was looking relatively clear, so we laid out the hundreds of trilobites in trays and decided which ones were good enough to go into the permanent collection. I identified quite a few of them, but it fell to Ed to carry out the laborious, repetitive work of cataloguing each specimen.

*These trilobites are almost all incomplete because most trilobite fossils are from pieces of exoskeleton left behind when the animals moulted in ancient tropical seas. For the fossils at Stony Mountain, wave and current action on the ancient seafloor caused further abrasion and breakage.

By Dr. Graham Young, past Curator of Palaeontology & Geology

In my last blog post, introducing our plesiosaur exhibit,  I promised to follow up with some of the story of how the collectors found, extracted, and prepared the fossils. When I was assembling the exhibit I interviewed Kevin Conlin and Wayne Buckley, since they tell these stories so much better than I ever could. Here are the interviews, which are also on the panels within the exhibit.

How do you find the fossils?

When I first got into collecting I didn’t know much about rock types. After taking some geology in school and university I began to recognize and distinguish rocks that would house fossils – the types of sediments or fossils in the area really dictate how you find fossils. I look for the odd shapes, textures, any variations in the surface of matrix or sediment which could indicate something other than just mud, sand or sedimentary rock. It could be anything from a pin prick to the size of a 200-pound boulder!

What do you do to prepare the fossils?

Depending on the fossil and its fragility, I use a special glue. For cleaning and preparing fossils, miniature jackhammers and a miniature sandblasting unit are used to remove sediment. It all depends on the fragility. Some fossils come naturally cleaned by the elements. Others still encased in rock can take hundreds of hours of preparation.

What do you have to do to pull out a fossil you have found? What sorts of tools do you use?

I suppose the most important tool is a shovel; we do a lot of digging! Then we get the picks and crowbars to lever out big chunks of shale. As we get further into the rock it becomes quite hard, and I use a small jackhammer. Once the fossil is exposed, we need to prepare a trench around it, then cover it with a burlap and plaster cast. We’ve used various techniques to get fossils out of the bush. Early on it was mainly inner tubes with a piece of plywood – we would drag and float it out. Later I made a skid that would float and we could haul that behind an Argo (an amphibious vehicle).

Among all the fossils you have found so far, which one is your favourite?

That’s easy. That plesiosaur that I just donated [to the Museum] is certainly my favourite.

What do you think is the most pleasurable part of fossil collecting?

Well, I guess there are really two things that come to mind. First of all, there’s the thrill of making a discovery. That, however, is fairly rare. Probably just as important is that I enjoy being out in the bush. I really enjoy the relaxation that comes with eating my lunch on a vantage point, listening to the silence and watching the birds and other animals.

By Dr. Graham Young, past Curator of Palaeontology & Geology

The Old Plesiosaur and the Sea Exhibit, Open November 14, 2014 – April 6, 2015

The exhibit itself is partly tied to a donation to the Museum. This spring, Wayne Buckley very generously donated a plesiosaur, the skeleton of a huge swimming reptile that he had collected, prepared, and studied over a period of several years (hence the name of this exhibit). We are planning a major new gallery exhibit that will feature this fossil, but we wanted to share it with the Museum’s visitors as soon as possible, and this temporary exhibit seemed like a wonderful opportunity to also display some of Wayne and Kevin’s other fossils.

The photos below simply show parts of the exhibit, and some of the behind-the-scenes work that was required to put the specimens there. I will try to follow up in a week or so with some of the very interesting story of Wayne and Kevin’s fossil collecting.

By Dr. Graham Young, past Curator of Palaeontology & Geology

Travels in the Hudson Bay Lowlands, August, 2014

Manitoba is an immense place, very slightly larger than France. If you look at the map, you will see that roads here are concentrated in the southernmost part of the province. The farther north you go, the fewer areas you will find that are easy to visit. Those of us who work in field-based sciences occasionally get to some of the more out-of-the way places, but most of us have still seen only a small fraction of what this province has to offer. The Manitoba landscapes that are familiar to us are either the parts that we have seen (such as the prairies and the big lakes), or those that are regularly depicted in photographs and tourist brochures (such as a few places in the boreal forest and the rocky shoreline around Churchill).

This fact was really brought home to me during the last week of August, as I was invited to participate in some northern fieldwork organized by my colleagues at the Manitoba Geological Survey. I have seen a good few parts of southern and central Manitoba, but in the northern third of the province I really only know the Churchill area. Nevertheless, I thought I had a good feel for what the areas away from Churchill might be like. Our plan for this trip was to visit some of the geological sites in the Churchill area, but also to take advantage of funding support for helicopter time, which would allow us to visit a few places far up the Churchill River, 100 kilometres from any road and far from the Hudson Bay Railway.

The helicopter travel turned out to be an eye-opening experience. The up-river sites had received some study from scientists working with the Geological Survey of Canada, who visited this area 50 to 60 years ago, so I knew something of what I would see in terms of the rocks and fossils: the bedrock exposures are very good, and many of the fossils are superb (though they are not generally as abundant as I had anticipated).

More than a decade ago we had overflown a few of these up-river sites when we had a bit of helicopter time in Churchill, so I should have really known what it would be like there, but seeing them from the ground was quite different. The Churchill River landscape has a tremendous sweep and grandeur. The river is very wide and flows swiftly, sometimes in an almost straight line, more often with gentle bends. Some downstream areas have bars of gravel and cobbles, but farther upstream there are several sets of treacherous-looking rapids. The valley walls steepen as you travel upstream, from the flat lowlands south of Churchill to a substantial height of land 100 kilometres upstream where the valley walls are cliffs of Ordovician bedrock, resting on the Precambrian granitic rock that makes up the river bed.

Portage Chute, Bad Cache Rapids, Surprise Creek, Caution Creek, Chasm Creek . . . the place names alone should be enough to tell you that you aren’t on the prairies any more. Honestly, if I had been somehow sedated and delivered into the ravine of Chasm Creek without any awareness of how I arrived there, I would have thought that it had to be somewhere in the Yukon or perhaps the Northwest Territories.

The valley of the Churchill River is a literally awesome place, breathtaking in its grandeur, its scale, and in the variety of landforms and organisms. It is absolutely a northern place, a place that Manitobans should be aware of, a place to celebrate!