Subscribe
Share
Share
Embed
Big Ideas TXST goes inside the fascinating minds forging innovation, research and creativity at Texas State University and beyond. Hosted by Daniel Seed, episodes showcase the thought leaders, breakthroughs and creative expression making the world a better place, one BIG idea at a time. Produced by the Division of University Marketing and Communications at Texas State.
Dan Seed (00:00):
Hello and welcome to Big Ideas, the podcast from Texas State University in San Marcus, Texas. I'm your host, Dan Seed from the School of Journalism and Mass Communication. This month we're joined by Dr. Shelley ett, a senior lecturer in the Department of Geography and Environmental Studies, who along with a handful of colleagues from other universities, made a discovery 490 million years in waiting. Dr. ETT studies, paleontology and application of fossils for resolving geological time, ancient environments, and paleo geography, which should give you a little bit of a clue of what we might be talking about today. Dr. Ornette, thanks to you so much for being here.
Shelly Wernette (00:38):
I'm thrilled to be here. Thanks for having me.
Dan Seed (00:40):
And this is an area of study that really is so fascinating. I think it grabs most of us when we're kids. Walk us through your journey into your field and what excites you about it.
Shelly Wernette (00:53):
I was definitely one of those kids that got grabbed by it early on. I was that dinosaur enthusiast who went to the public library at least once a week and came home with a stack of books as tall as my head, but I lost touch with it for a long time there. I didn't actually go to school for the purpose of becoming a paleontologist. I thought I wanted to do archeology. Wasn't sure there was a career field out there with just an anthropology undergraduate though. So I ended up doing geology as a science to approach the archeology and just fell in love with geology and then the specialty of paleontology. So first and foremost, I consider myself a geologist, and then I used the fossil record to answer geological questions.
Dan Seed (01:35):
So initially for you, what fascinated you about dinosaurs and paleontology, and then as it evolved into geography and all that, what drew you to it? Is it just the way your mind works or is it just so interesting to you?
Shelly Wernette (01:50):
I think it did have to do with interactive parts, which is how my mind works. I like to think about systems and how things relate to each other. And so with something like dinosaurs, it wasn't just all the names and the cool animals themselves, but it was the idea that you could look at a tooth and say, did this eat, meet? Did this eat plants? And if you know a little bit about the tooth, what else can you say? Okay, then what for? What kind of defense mechanisms do they have? And so you can start to piece together a whole picture of how something behaves, how it interacts with the world, start to look at that. They come in different ages and you have some that show up with certain body plans earlier, and then others that have different body designs later. And this idea of just a lot of interaction between the animals and their environments and then interpreting environments from what animals you have in there. And now, including in my research, we can look back and say, how high were the oceans? What was the climate? Where were the continents? That was a big part of my research is these continents weren't in the same places as they are today. Southeast Asia was not next to India, but when we look back and we look at the animals, I could, oh, actually it was next to Australia and North China. It was in a completely different place. And so I find that all really interesting.
Dan Seed (03:06):
And so what I alluded to in the introduction, you and your team have identified 10 previously unknown species of trilobytes hidden for 490 million years in a little studied part of Thailand. These along with about 30 other species of trilobytes, your group found there could be missing pieces in an intricate puzzle, as you talked about, of this ancient world. Geography. Talk a little bit about that.
Shelly Wernette (03:32):
The new species are cool because it suggests that this area didn't have a tremendous amount of interaction with other parts of the landscape. So if you think about going to an island today, like Australia is an island continent, Australia is animals that aren't known anywhere else. You don't see the kangaroos and the wombats and the koalas, my personal favorite, the Kuka, although I'm not sure how to pronounce their name, you see these animals in Australia that you're not going to find anywhere else. And then when people got to the Americas, whether it was the indigenous people hunting across early on and they start hunting bison instead of just mammoths or if it's modern or not modern, but more modern, Europeans coming over and seeing new animals for the first time. We know that animals are located to different areas. And the more specialized, the more isolated the group of animals is, the more it tells you that area was restricted and cut off from the previously known areas. Typically islands sometimes when we're dealing with ocean basins and trilobytes lived in the ocean, so it might be just there was a barrier reef that was keeping them separated from the main part of the ocean. But we know that even though these animals were fairly close to Australia, because you do have some overlap there, they were separated enough geographically that you also get these 10 unique species including two unique genera that you don't see anywhere else. And genera are genera. A genus is a slightly broader grouping than a species.
Dan Seed (05:05):
So I've mentioned it a couple times now. Trilobytes, describe for our audience what are trilobytes?
Shelly Wernette (05:12):
I sometimes like to describe them as underwater cockroaches with scissors for legs. They are
Dan Seed (05:18):
The, that sounds horrific. I'm sorry. Yeah.
Shelly Wernette (05:21):
So if you know about Isop pods and rolly pollies are a type of isopod. They've got these bands that allow them to take their shell and roll up into a little ball. And trilobytes are like that as well. But they're not related to iso pods. They're more closely related to different, well, we're not entirely sure, but we think probably most closely related to the crustacean and insect grouping. Some cool things about them is their name. Tri Lobe refers to, they have a center lobe that runs down their body, a center kind of bulbus area, and that runs from the head part and then all of the little separate bands of shell that make up their middles. And then all the way to their tail, there's a central kind of oval shaped bulge through the middle, and then the two sides of the head, two sides of the middle, and then two sides of the tail.
(06:11):
Those two sides plus the middle lobe equal the try lobe. The scissors for legs thing I referenced, because trilobytes have two sets of legs that go under all their segments. They have a whole bunch of legs just like rolly pullies, and one of those sets of legs has a gill on it. And the other sets set of legs has these little bulges that have spikes on them that they use to move and process their food and cut things up. And so they have very hard shells, kind of a unique shell design. They roll up into balls and they've got these weird legs. So I hope that gives a little bit of a picture of them. They live from 540 million to 250 million years ago in the ocean, no modern descendants.
Dan Seed (06:57):
And looking at the pictures of them, people can go online and Google this, but you can see exactly what Dr. Warn net's talking about when you look at them. And the idea of the rolly polly, if you were to take a rolly polly and kind of pull it out and stick it in dirt, the shape that they make is kind of similar to that from what I look at and see. So describe for us this research that your team conducted, the process of discovering these trilobytes. Let's start there. How did this whole thing come about?
Shelly Wernette (07:27):
So this was my PhD program. So when I came into it, it was working with a group that had already been looking at Trilobytes and the geography of the Himalayas. And the group was wanting to move further around the Himalayan Mountains, kind of wraparound into Burma. And then Burma at the time was geographically connected to Thailand, and Burma is also known as Myanmar. So I'll give it both those names here. So my role in when I came in on it, there was literature already out there on the Trilobytes, a guy named John Shergold from Australia. And then another person, Dr. Coi from Japan, had both looked at Trilobytes here before both of those papers. And there were only two and a half papers on them. I say a half because one of them had four species published, but only one new name. Very, very short papers with very open-ended species, not something we could do anything with it to understand the geography.
(08:26):
They took some pictures, they didn't really put any firm names on them. So when I started looking at Thailand and wanting to work out its position in geography relative to Myanmar and to India, I needed to know what's there, what species are there. And so we went back and we collected a whole bunch of fossils. And when I say a whole bunch, I think we spent $600 shipping fossils on our first trip from Thailand back to California. This was while I was a grad student in California. We worked, I guess two weeks total in Thailand to collect the fossils. The fossils are preserved in rock on the island of Taral, which is part of the Satum global Geo Park, brand new global Geo Park. Our research was part of getting that established with unesco, but we would take a boat around to different outcrops on the island, hop out of the boat, hop up to the rocks, take sledgehammers, chisels, smaller rock hammers, whatever it took, find rock that we could see the fossils in, put them in a bag and ship them back to California where I could work on it in the lab.
Dan Seed (09:28):
How far down in the rocks are these? You have to dig very far, and you must have to be very careful. I mean, you're describing chisels, but you've got to know what you're looking for and not do too much damage either.
Shelly Wernette (09:41):
So the nice thing about invertebrates rather than vertebrates and invertebrates are those things that don't have skeletal bones and backbone like we do. They have skeletons, but they're exoskeletons. The nice thing about invertebrates is they really are just sitting in the rock. If you go just at the surface, if you go hiking anywhere in this area, you are likely to come across a little image of a shell in a rock that's a fossil, and then you're going to possibly step on it and maybe you wear it down a little bit, but depending on where you are, there are hundreds of these things in the rock, thousands of these things. I lost track of how many fossils I processed. I think by the time it was all said and done, it was over 600 something fossils. It is a matter of just taking the rocks off the surface.
(10:26):
We don't go that far back. We don't have to do the thing that vertebrate paleontologists do where they map out where is the outline of the dinosaur fossil or the camelo fossil or whatever they're looking at, and try to take casts of it and really carefully lift out individual bones. If I broke open a rock and I saw some fossil material, then I wrapped it up in some newspaper and put it in the bag. There are some rocks that you can see more likely to have fossils in them if there's little, what's called a cochina texture, it's a pitted texture kind of air bubbles in the rock, and that might indicate that there's a layer of more concentrated fossil bits there. And so that way it was a little bit more directed where we would break open the rock and look. But sometimes it was just a matter of hitting every rock you can, and the more you hit, the better it goes. There are techniques for how to break them better than other breaks, but sometimes you take somebody out there who has no idea what they're doing and they hit the mother load. One of my trips, we had some folks along from a conference, so a lot of geologists will do conference excursions, and he was not a paleontologist. He's a different type of geologist. His name is Gabrielle Ian, and he had no idea what he was doing out there, but he's the one person from that trip I named a fossil after
Dan Seed (11:51):
Because
Shelly Wernette (11:51):
He hit a bed of rock that none of us thought would come up with any fossils. It just looked like mud. It was a really bad looking rock. And at the end of the trip, we're almost done for the day. We're actually wrapping everything up. And he goes, I think I might've found something. And I kind of ignore him at first because I don't know, it just didn't seem right that we'd kind of stepped over this thing and he pulls me back and I see the bed at first. I think there's nothing in there. And then when we look, there's more fossils in that bed than there is in any of the others we saw. And there are different fossils than we saw anywhere else. Maybe they liked this different type of ocean floor that left a different type of rock. I don't know. So I'm really thankful that he was there because none of the rest of us thought that looked like anything at all.
Dan Seed (12:34):
Was that an aha moment for you? When you see this area that he found and you look at these things, are you able to look at them and just kind of go, that one looks different, that's something completely different that we've never seen? Or do you have to analyze this later?
Shelly Wernette (12:48):
Both. So sometimes I know exactly what I'm looking at in terms of I've not seen it before, or I've definitely seen it before, and that can be really helpful in the field. It tells me it helps direct how much of that rock do I really need to collect In this case, I actually did recognize it from one of the papers, one of the other previous 1980s papers had published it, but they didn't attach a name and they only published one image and we hadn't found it anywhere else on the island. And it was important that we got this one identified because we didn't want to leave that random species out there that nobody knew what it was. And so I'm very thankful that I saw it. I recognized it. I knew we needed more of that because it wasn't identical to the other things. So sometimes there's some variation and you want to know how much does their head shape chain vary? How much does their size vary? Things like that. So it depends.
Dan Seed (13:40):
Yeah, it depends. And again, we're joined by Dr. Shelley Warren at a senior lecture lecturer in the Department of Geography and Environmental Studies. So you send these 600 or so of fossils back to California, and then that's where that analysis happens. Walk us through that. How do you start to look at these things and determine what's what and what's new and isn't?
Shelly Wernette (14:02):
So the first stage is what we call preparation, and that's the thing that people picture paleontologists doing where I take my chisels, my little tiny chisels, not my big rock splitting chisel, but my little chisels, some pneumatic drills, some dental looking tools. And I clean up the fossils because when I break open the rock and see it for the first time, which this is what a lot of paleontologists love about this is you make eye contact with these remains that literally haven't seen daylight in 498 million years. Wow. There's a popular paleontology book called Trilobyte Eyewitness to Evolution because it's this idea of they have recognizable eyes and you're looking at it in the eye for the first time in eons. So I clean up the fossils where I can see the rest of it as much as possible. Sometimes they might have broken from prior to burial, they might have chemically dissolved a little bit, but I get them as cleaned up as I can.
(14:59):
And then comes the photography stage. I don't do most of my interpretations directly from looking at the rock itself. I take a lot of photographs and then I go through the photographs to do the interpretations. So normally I photograph it from the top looking down, I'll photograph it from the side from the front, get a whole bunch of shots. Nowadays people are doing more 3D scanning, but with a whole bunch of specimens that is very time consuming and expensive when it comes to data storage. So I haven't been doing that. But with something like a dinosaur school, you would, so I do a whole bunch of photographs, and then the interpretation part, I sometimes refer to it as graduate level spot, the differences. I go through old literature, literature that was published from Australia, China, Vietnam, Korea, anywhere I could get my hands on that I think might be related to this stuff.
(15:53):
And I go through what fossils other people have found, and I look at the definition of how they define different species or different groupings. And one by one, I try to connect the fossils to those pictures. Normally I start with the heads. Those are more distinct. And then I'll try, once I can identify a head, I'll try to match or at least a broad grouping that the head goes in, then I'll try to match a tail because the heads and tails when we find them, they're not connected. Their skeletons get broken up and scattered before they get buried. So there's also a matching process of trying to put things back together.
Dan Seed (16:25):
And so you do that visual identification, which gives you a sense of differences and identifying different types and species of them. But then the other part of the work is analyzing, I would imagine the not chemical makeup, but the different compounds the isotopes found in them, which then ties into how old they are and maybe where they were in geography.
Shelly Wernette (16:50):
So this is partially true that we do use isotopes to tell age, however, those isotopes are not coming from the fossils
(16:57):
In between the layers with the fossils, we have layers with ash beds, old volcanic ashes, sedimentary materials. Don't hold on to the age of formation. Well, there's a whole bunch of reasons. But the minerals that we find in sedimentary rocks, like what the fossils form those minerals are going to come from the age when that rock, when the individual grains first form. So if you think of like a beach, all of the sand on a beach within that sand, there's going to be some minerals that we can get dates from. Usually there are a mineral called zon. So within all the quart sand, there's a few zon crystals. And the zon crystals will not give the age. When they got to the beach, they'll give the age when they first formed in volcanoes somewhere way inland, and then gradually got eroded and washed away to the beach.
(17:45):
So what we're looking for are those volcanic rocks, the rocks that actually form the crystals as they erupted. And they dropped straight onto that beach, or not beach, but into the shallow marine water there. So I have a colleague at a Princeton, he's doing the dating of the ash beds. That's a much more technically and chemically complicated system that we did not have the technology for. It takes a lot of lab space and a lot of lab equipment, and that's going to be a different paper, is getting the actual dates off the volcanic ash beds. Then we'll take the ash beds and apply those dates to the fossils, and then we'll take the fossils and correlate the dates from the ash bed to other locations that have similar fossils.
Dan Seed (18:28):
And that helps create that jigsaw puzzle that you were talking about of what used to be where. And now it's down here and there's that similarity.
Shelly Wernette (18:36):
Well, no, that's a different process. Different process. The dates will be part of the geologic timescale. Our fossils are right on the boundary between two periods called the Cambrian and the Orion. We actually have some Orion fossils as well as Cambrian, and both of them have ash beds in them. Whenever you look at a geologic timescale, things like the zoic, the dates that you see on those come from these ash beds from various different places across the world. The names come from the fossils. So I name what time period we're in based on the fossils, and then we give that time period a date based on the ash beds. Now, when it comes to the map part of it, what we call the paleo geography or the ancient geography, that part comes from comparing fossils from different locations. So I actually have some tables in the paper and I created a spreadsheet of them that have around the world, where do we find the same species or the same genus as what we find in this assemblage of fossils. And I looked at places alike, what lcia, which is another word for North America, the ancient North American continent, Siberia, the Baltics, Kazakhstan, north and South China, because geographically those are actually separate continental terrains. And I take all of these different terrains. I make a big spreadsheet about where the same thing occurs in each one, and then I use those common occurrences to look at what most likely was related, geographically related
Dan Seed (20:04):
Right from this research here, what kind of picture does a paint of what the world looked like during this time period?
Shelly Wernette (20:12):
Most of the world, we already had a pretty good picture, the Sibu Masu Terrain, which is the name of the terrain that contains Myanmar in Thailand. Sibu Masu was kind of on the outskirts of the big continent called gun. And Gun has most of Africa, parts of Europe, Australia, Antarctica, India, south America, and all of those relative positions were already pretty well known. And so we're looking at these smaller continental blocks that were floating around the edges, so north and south China, and then sibu Masu by finding that Sibu Masu is similar to Australia as well as North and South China. In my Paleo geographic interpretation, I show it kind of attached right on the edge, just pressed up against the edge of Australia and the North China and South China just sit right on the other side of Sibu Masu. So kind of a strip of land with a little bit of ocean separating it from the two Chinese blocks.
Dan Seed (21:11):
And so this kind of research too, being able to understand where we were or when I say we, the earth itself, and the placement of continents and land masses back then, how does that help us maybe understand what's happening now or what's to come?
Shelly Wernette (21:29):
Yeah, going way back, what this helps us understand is where a mineral resource is going to be if you know that there are some sort of lithium ore, not that this is a big thing in Thailand, but let's see, Thailand has zinc. So if you know that there's a zinc deposit right in the mountains of Thailand, and you know that it formed 500 million years ago, well, that zinc deposit might be continuous with another continent that it was pressed up against at that time. So we see this especially from the breakup of Pangaea, that's the one most people are familiar with, not the only supercontinent we've ever had. It's just the most well known one. When we go up to Maine and up into the region, that kind gets called velonia in Paleogeography, a lot of those rocks correspond with rocks in Europe, and you can follow some of these mountain deposit mountain areas, some volcanic areas right across the Atlantic. And so it really helps open up possibilities for mineral exploration. It also helps us better understand geographic trends. Now, 500 million years ago, a lot of those geographic trends got kind of overprinted once we get into Pangea. But if you want to understand the differences between old world and new world monkeys, that's a Pangaea thing. Australia having marsupials while the other continents have placental mammals, that's a continental breakup issue. And so we can look at these trends in different animals over time and see where the continents have moved around.
Dan Seed (22:58):
Very interesting stuff, fascinating stuff. What was the most exciting discovery for you as part of this research?
Shelly Wernette (23:05):
You would think it would be the new species, but it's actually finding the species that were previously known. So there are a couple of things, like I found one that was previously only known from North America, which is really unusual because in order for them to get from North America over into this WAN region as it was at the time, it suggests that either they were getting across the ocean somehow, and these are not open ocean swimmers, so maybe it had some larvae floating across, but probably North America was closer to this region than we thought it was previously. And so finding shared species was the most exciting thing to me. I could actually base geography on the shared species. I think that was the most exciting discovery. The whole thing in general, too, while I was working in Thailand, I was also working up in Myanmar on some things and getting to go to Myanmar and their brief interval of time between military junta was pretty cool because not a lot of people have gone there just for travel. And then while there, we collected the first ever Cambrian fossils be published from Myanmar. They haven't had a lot of paleontological work done up in the mountains, at least not on the invertebrates, a little bit more on the dinosaurs and later animals, but not the early ones.
Dan Seed (24:20):
So we're running up on time here. So I have a couple more questions for you. I guess going back to these discoveries that you made here and what you observed, thinking back to little Shelly coming back with the library books as tall as her head and being interested in this, does it blow your mind that you get to do this and do it to this level and make these kind of discoveries now?
Shelly Wernette (24:41):
I think it does, yeah. I definitely don't think I saw myself doing this, especially not traveling around and going to these places and collecting it off the beach, jumping in and out, watching the tides to make sure we didn't get stranded. I've been doing a lot more than I expected ever to do. And then having papers out that I kind of once joked that if I had more than five scientific papers, I'd keep my name and not change it whenever I get married at some point. And at this point, I'm like, well, that's surpassed, and I didn't expect it to be surpassed before getting out of grad school. And then I've gotten invited to talk at some conferences over in Asia because these fossils are really near and dear to the local people there. The entire UNESCO Geo Park is based on fossils and caves and geology, and we got to help provide the scientific evidence on why that should be a UNESCO Global Geo Park there in Thailand. Sitting on those meetings and seeing how important it was to the local people and their tourism industry and all of that was very cool.
Dan Seed (25:39):
Yeah, incredibly important work. So you do this research and like anybody at a university, the next question is, what's next? Anything in the pipeline for you?
Shelly Wernette (25:48):
So it's mostly in the pipeline is we're waiting on our colleagues that work on the isotope data, the absolute dates, and I will help make sure the fossils get integrated to the dates correctly, and then we can correlate them on a later paper on that. I'm not currently doing any research in terms of new material coming out. Like you said on the senior lecturer, my main focus is on teaching. I've got some educational research ideas I'd like to follow up on, but mostly right now I'm working to consult and help my colleagues carry forward with the work that we did there in Thailand.
Dan Seed (26:22):
Well, it's fascinating work. Dr. Shelley ett, thank you so much for joining us and being here.
Shelly Wernette (26:27):
All right. Thank you so much for having me,
Dan Seed (26:28):
And thank you all for the privilege of your time and downloading and listening to another episode of Big Ideas. We'll be back next month with another episode. Until then, stay well and stay informed.
Page 1 of 2