Saturday, April 30, 2011

Hadrosaurs! by Rachel Hatton-Ward

The field trip we went on was so cool! It basically combined all of my favorite things, like dinosaurs, camping, and playing in the dirt. We got to see all kinds of bones, tear out a ton of rocks and dirt, a tree, and a bush with a lot of pollen, hang out with awesome paleontologists, and do plenty of hiking and camping. It was great! The bones we found were mostly from Hadrosaurs, and I really thought it would be interesting to learn more about them now after I got to see so many of their remains out in the field.

Hadrosaurs lived during the late Cretaceous Period in areas with warm, wet climates. They had flat "duck bill" mouths that probably helped them chew tough plants, and large crests on the back of their heads. We found a piece of paper that showed that males had long crests and females had shorter, sharper curved crests, but Alan explained to us that that idea was wrong and they were completely different species that lived at different times!

Hadrosaurs were huge, from 10-40 feet long, and they had three toes on their feet. After a full day of digging, we found fossilized toe, it was awesome!

Overall, the field trip was a lot of fun, a lot of work, and I feel like I learned a lot from it. Paleontology takes a lot of patience, but finding bones after searching all day was really rewarding, and I wouldn't mind learning more.

Dang Tree stop eating my bones by Maggie Dalene

Above: Rolling the tree stump down the hill.

As we were digging for fossils we ran in to a slight problem…. We had found fossils but a giant juniper roots had started to eat away some of the fossils. As the day went on the more fossils we found the more tree roots we had found with. The reason we found so many bones next to this juniper was because of the minerals that the fossils have. When the animal dies soil and water is put over them. As the water flows in and out minerals fill the cellular spaces and crystallize. The shape of the original plant or animal is preserved as rock. Sometimes the original material is dissolved away leaving the form and structure but none of the organic material remains. Trees love all of these minerals that the fossils have. So having the tree there was kind of a good thing because the roots helped push up some of the rock that was covering the fossils and it was a bad thing because they were eating them away.

The tree we had to kill to get to the bones.

The bones underneath the tree.

Plants of the Cretaceous by Kat Combs

The above picture is of the bark of an ancient relative of the common Cycads belonging to the order Bennettitales. These, along with most plants present in the Cretaceous were gymnosperms. Here's a bit of background: there are two main groups of plants, the more primitive gymnosperm, and the angiosperms. Gymno means naked and sperm means seed, examples of these are your typical conifer trees who's seeds, or cones, are not covered in an ovary. Angio meaning covered and sperm meaning seed, angiosperms are also known as the flowering plants. Most plants one thinks of now and days is an angiosperm such as Magnolias, tulips, apple trees, banana trees, etc. all of these having two key similarities: flowers and a seed covered in an ovary, fleshy like apples, or hard like nuts.

Before the lower Cretaceous, gymnosperms were the only plants around, but at the start of the lower Cretaceous, the first angiosperms began to show up. Angiosperm populations and diversity exploded after their first appearance. They had the advantage over gymnosperms in that they could reproduce and grow much faster when a disturbance, such as fire, killed off all the plant life in that area leaving room for the next generation to take over. That next generation being angiosperms. Though they were quick to take over, angiosperms didn't dominate until after the Cretaceous. So gymnosperms were still the dominating plant species found during the Cretaceous. Despite their relatively slow growth rate as compared to angiosperms, gymnosperms were diverse and found everywhere in the Cretaceous.

There is nothing today that can truly be compared to what it might have been like for the dinosaurs, though some areas like New Caledonia or eastern Australlia where they have the towering Araucaria trees could give you some idea, that mixed with a wide variety of vines and ferns much like you would find in tropical rain forests today; just not the same types of species. During the Cretaceous period the earth was much warmer than normal with raised sea levels. During our trip we found several fossilized tree deposits just in the site we were working, as shown in the picture below. Gypsum was present in the tree as was a core of coal (the black seen in the center of the tree trunk).

As the plants thrived so did the dinosaurs. One might think, given the enormous size of the herbaceous dinosaurs and the typical slow growth rate of gymnosperms, how could they possibly have had enough to eat? A possible hypothesis is that the presence of a fast growing, parasitic, gymnosperm leafy vine that would cover the trees in a green, edible blanket.
Some plants typical in the ancient rain forest would be small amounts of angiosperms, adding a splash of flowery color like magnolia, ancient towering conifer trees with needles and others with broad, flat leaves like the Ginkgo trees still found today, blankets of ferns covering the ground, vines twisting and spiraling up trees toward the sky; everything green and warm.

This trip was a blast and very educational (and sunny, with not enough sunscreen). Picturing how it might have been when the great reptiles were wandering the planet left me wishing I could see it, or at least go to Washington state and New Caledonia to get a mixed sense of what was going on.

Friday, April 29, 2011

On an Adventure to Find Bones- By: Derek Nielsen

First off, I want to tell you how much fun I had on this field trip. It's not everyday that you get to go and dig for fossils with a paleontologist. It was a blast. Anyone who is given the opportunity to go on any trip like this should take it. You won't regret it.
Now, before you can dig up your fossils, you have to find them, and you might be asking yourself, "how can I find some fossils?" The first part is easy, you do a little research and find out what areas have a surplus of bones. As you'll read from some of the other posts, the Grand Staircase National Monument is full of them, especially around Cretaceous layers. Anyway, when you find a good area, you will need to look in the right places. If you look at the picture I have here, you will notice that there are lots of little valleys like this one. Because of continuous erosion, this is the best place to look. As the layers are being washed away it will cause pieces of the bones or other fossils to come loose. They will travel down the slopes to the bottom of these valleys.(notice the red arrow) So you'll want to walk around the bottom or at the top were they could just have started to become exposed. Make sure you have a hand-lens at the ready to use if you think you have found a fossil.

In this area the bones tend to have an orange "rusty color", look for that. Also if you think you have found a piece, look at it with the hand-lens and check for a porous area in the middle. Bones have these porous area inside because of the bone marrow that would be inside when the animal was alive. One last test that you could do is lick it. Yes I said 'lick', like with your tongue. Because the bone is porous, the bone will slightly stick to your tongue.
Once you've found a piece, you'll want to travel up the hill from where you found it, because they travel downhill because of gravity. On my picture, you will see a yellow line, this would be if you had found a piece at the bottom of the hill and then followed the line up-hill to find more bone. You will know where to start digging when you have found the highest piece of bone, because it won't travel up hill. Through my experience in searching for bones, I have noticed that they tend to be around the harder layers that appear in the slopes, indicated with the green arrow. So as you look, look for these layers of harder sandstones and mud-stones. But, you must be aware that taking any bones from a public land illegal. If you find anything of value, tell the park services, who knows, maybe they will name a new species of dino after you.

On the trip, I was looking for bones as I have described above, and I found some pieces of turtle shells. It turns out, after looking around some more, that we had found an area that the paleontologists call a turtle dam. There was once a river that ran in the Cretaceous that had logs that had gotten stuck, and so turtles would get stuck in the logs and die. This is why we had found so many parts of turtles and petrified wood all over that area.
Finding bones and other fossils is fun and really easy to do. You should plan to go on a camp out or a field trip and try it out. But remember: it is illegal to collect any bones from any animal that had a vertebrae

Uncovering a Hadrosaur by Mat Hilton

When we arrived at the paleontology lab we immediately began snooping around. There was a group of fossils in one corner of the room that had been brought in all together in some kind of plaster.
When Dr. Titus came back we had lots of questions about it. We had decided it was the skull. We found out we were right but wrong about everything else. We were trying to match the skull with the drawing in the bottom right of the picture. It turned out we were looking at the skull backwards. We also learned that the picture is based off of a disproved hypothesis about the length of the crests being distinctive to gender. Dr. Titus told us it was a hadrosaur skull. This was very significant to us because we would be working on a hadrosaur fossil.
At the dig site there were several bones already exposed. Even though the bones were very weathered it was really exciting and got us motivated to work and find more.
I didn't know anything about hadrosaurs before this trip, but after spending so much time digging up pieces of one I really wanted to learn more.
Hadrosaurs are what most people know as "duck-billed" dinosaurs. They are members of the hadrosauridae family. There are two sub-families that are distinguished by having hollow cranial crests or a solid crest if any.
Distinguishing characteristics of hadrosaurs are the bill-like snout and a jaw that moves in a very strange way. I don't know if any other dinosaurs had a similar jaw, but no animals alive today have one like it.
Hadrosaurs had thousands of tiny teeth and the upper jaw is hinged in a way that allows it to expand outwards thus making a grinding motion to break down vegetation. This was likely a very important adaptation that gave the hadrosaurs an advantage. This method of grinding food is more advanced than other herbivores which relied on the use of gastroliths (gizzard stone).

The trip was a lot of fun. Even though I got sunburned, dehydrated, and worked until I lost the use of my arms it was definitely worth it. I learned that I'm definitely not cut out to be a paleontologist, but seeing a small portion of their process expanded my understanding of this branch of science.

Thursday, April 28, 2011

Climate of the Cretaceous

During the late Cretaceous, Utah was around in the same place as it is today (meaning, same latitude, same longitude). That, however, does that mean that we had the same climate back then as we do today. The climate in Utah was hotter during this time because of increased volcanic activity, which released large amounts of carbon dioxide into the air. This increase in carbon dioxide upped the greenhouse effect back then, causing warming throughout the globe.

The warmer climate caused sea level to rise. Another process helped this as well. Ocean ridges are found on the seafloor at divergent boundaries where two plates are pulling away from each other and new crust is born. During the Cretaceous the plates were spreading extremely rapidly. This caused oceanic ridges to be elevated. When they do this they also push up the water, so the ocean water had to flow in somewhere and there happened to be a low ground right down the middle of the North American continent. Thus, half of Utah was under an arm of the ocean, and that arm would cover the interior of the U.S.

Unfortunately the ocean flooded out and the wet climate changed to dry, so we also had no beach to go swim in, but that doesn’t mean we didn’t have a good time. I think that my personal favorite thing that we did was the “Manual Labor." I had tons of fun digging through rocks and looking for clues. Sure, the first few hours proved fruitless, with me and Jessica finding only a few shells and one really ugly bug, but we knew that we were getting closer to our goal.

Once we started finding real bone things got exciting. I personally found two ribs, both of which were pretty “rotted out”, which basically means that they were in really bad shape. Scott Richardson marked them down on his chart and then wiped them away. We also found a really cool toe bone and one really strange looking bone that Scott was pretty sure was just another messed up rib but by the end of the day he still wasn’t 100% sure on what it was.

I had so much fun on this trip. I met many great people and I will always remember working on real dinosaur bones. I hope to return some day and help them on another dig site – and that time we’ll have to find to the skull. It’s right around the corner, I can feel it! ~Tauni

Monday, April 18, 2011

We just returned from another great trip to the Grand Staircase-Escalante National Monument. Nine Snow College students worked with Scott Richardson and Dr Alan Titus excavating a hadrosaur in the Kaiparowits. The students ferried loads down to the site and spent Saturday 4/16 moving rock and vegetation to expose more bone - toes and ribs and tendons. It was a fantastic field trip and an amazing opportunity for all of us. Thanks Dr Titus, Scott R and the BLM for hosting us.