Remember Yukon Cornelius? He's the fella with a large beard that helped Rudolph and Hermey find the Land of Misfit Toys and defeat Bumble? Well, not really defeat Bumble, but pull his tooth? Remember him? He sang a song, 'Silver And Gold'.
And look up in the picture! It's a bird! It's a plane! No you fools....it's a gold fossil! Geez....
And it's not even real gold. It's iron pyrite. Remember a few weeks back when I showed a couple of fossils that had their original minerals replaced with others? One was opalized and the other was pyritized.
Aw heck, I'm getting ahead of myself. Let me back up here for a minute. Today is Friday, and that means this is Friday Rocks. It's my weekly indulgence in rocks with dead stuff.
In previous posts I've told you about important people in the field of fossils. People like Gideon Mantel, Richard Owen, William Buckland and Mary Anning. Wait....I haven't told you the story of Mary Anning? Really? I should do that some day. But not today. Today I want to tell you about two men who were friends, then enemies, and between them, they advanced our knowledge of dinosaurs immensely.
Edward Drinker Cope and Othniel Charles Marsh. From the 1870's until the 1890's, they found and named a combined 142 species of dinosaurs. But because they were in competition with each other, they rushed. Only 32 of the species they named are recognized as valid today. They were responsible for the dinosaur everyone knows about that didn't actually exist, the Brontosaurus.
So what's the deal? Both men were wealthy. And both men loved paleontology. Their combined interests led them to become friends when they met in 1864. But because they were both basically douchebags, they ended up disliking each other. Not only disliking each other, but determined to ruin the careers/reputations of each other. They spent the next 30 years sabotaging dig sites, destroying fossils, working to get funding revoked, and even physically fighting with each other.
Oh lordy, it's a highly entertaining story. And I'm just not a talented enough writer to do the full story justice. Plus, it would take up more space in this post than I want to devote to it, so I'm going to recommend you read up on it yourself. You can read the quick and dirty wiki about it, or you can read the book The Gilded Dinosaur, or you can check out the documentary PBS did on it. Any of those options will do a better job than I explaining it.
Besides, I want to get to my fossils. As you can see, there are two fossils on that slab. One is pyritized and the other isn't. They are both Triarthrus eatoni, and it comes from the Lorraine Shale formation in New York. And it's one of my favorites. Why? well, the pyritized example is a ventral view. That means you're looking at the underside of it. And I really wish I had a better camera. Because it has soft tissue preservation. You can easily see the two antenna coming out the top of it's head. What's more difficult to make out in the photos are the legs and guts.
Yeah, second picture isn't any better than the first. But you can kind of make out a few of the legs, and the glob of gold in the top 1/3 is actually it's stomach. If you could look at the actual specimen with a magnifying glass you would be able to make out much more detail.
And that's the subject of todays fossils; soft tissue preservation. As rare as fossils are, soft tissue is even rarer. The conditions needed to preserve tissue don't occur in most fossiliferous beds. There are a few locations around the world where soft tissue is more likely. The Lorraine Shale Formation in NY is one of them. The Chengjiang biota which is part of the larger Maotianshan Shales in China is another. And that's where the following examples come from.
There are about 40 Cambrian sites around the world where non-mineralized soft tissue preservation is found. (the Lorraine Shales is an example of mineralized tissue preservation). The most famous of these locations is the Burgess Shale in British Columbia. Not only was the Burgess Shale the first site found, it has produced some of the best examples. That's not to say other locations aren't just as spectacular.
All the following Chengjiang fossils were collected before the export ban was enacted. They are all legal for private collectors to own and sell. I respect the right for any nation to own any fossils found in their territories if they so choose.
This was the first soft tissue example I acquired. It is a Leanchoilia. It's not a trilobite, but it is an arthropod. If the two specimens look similar, that's because they are the same critter. This was a rock that has been split in two and the fossil is on both halves of the matrix. You can see the rough outline of the roundish head at the top of the examples, and the frills out to the sides are it's legs. Not only does this example show some excellent tissue preservation, it's two, two, two fossils in one!
Believe it or not, this was the best picture I could get of this example. And it's really hard to make out in the pictures. But what it is is a Naraoia. You can see it as that red smudge of smoosh at the top center of the matrix. The darker red you can see is the digestive track, and the light red frill at the bottom are it's legs. Naraoia is known as a trilobitomorph. This is a critter that has some similar characteristics to trilobites, but aren't actually the same as a trilobite. For example, Naraoia only has two sections in it's body plan, cephalon and thorax. No one is really certain what the exact relationship between Naraoia and trilobites are. Naraoia may be precursors to trilobites, or they may not.
This is a Wiwaxia. I have this one not because it's a fantastic example, but because it's a type specimen. Mine looks just like a blob. But in life, that blob would have been covered in small scales and small spines. (the scales and spines didn't fossilize, but the body did. Go figure...)
I have other examples of soft tissue fossils including part of a grasping appendage from an Anomalocaris, a Waptia, and an Ioxsys. Right now I can't get decent pictures of them, but I'll be upgrading my phone in a couple of weeks, so maybe then. But for now, I think I've given you enough Cambrian soft tissue to tide you over for a while. While these fossils might not look like much, if I were a better teacher, you'd be more able to appreciate what you're seeing.
If you have any interest in reading up on fossils like these and the creatures that made them, I recommend The Crucible Of Creation by Simon Conway Morris, Trilobite: Eyewitness To Evoloution by Richard Fortey and The Cambrian Fossils Of Chengjiang, China by Xian-guag Hou et al.
And now it's time for me to go finish my Friday so I can enjoy my Saturday. See you Monday unless I see you earlier in which case it'll be before Monday. Oh hell....just have a Good Friday, (get it...) and an Happy Easter.