Saturday, April 12, 2008

It's a blog explosion!

Our paleontologists have had such a blast sharing their doings with you that we've created a new HMNS blog - BEYONDbones - so that all our other kinds of scientists can share their news and experiences with you, too.

What's it like to raise a tarantula? How many stars, planets and other celestial objects can you see in the night sky this month? Can you make a backyard garden into your own private Cockrell Butterfly Center? We've got dozens of bloggers from all corners of the Museum who can't wait to share.

I hope you'll take a moment to check it out - and leave us a comment to let us know what you think.

In other good news, the paleo team is headed back into the field this week, so we'll have more news and pictures of what they find for you soon.

Thursday, March 27, 2008

Mummified dinosaur comes to HMNS

We're excited to announce that Leonardo, the famous mummified dinosaur from Malta, Montana, is coming to the Houston Museum of Natural Science this September for its world premiere display.


The fossil block, weighing 6.5 tons, reveals secrets that would not be evident from bones alone. For example, note the pouch under the throat – it may be a crop, to store food – a feature that also exists in modern birds. Photo by Grant Delin.

Leonoardo is one of only a very few big dinosaurs with preserved skin - and it covers 90% of his body. What makes him truly extraordinary is that his stomach contents - his last meal - are preserved. Until his discovery, scientists could only theorize what plant-eating dinosaurs ate. Now we know.

You can see video of this astounding fossil here. The link also includes photos of skin texture, illustrations of Leonardo in life, and more information about the exhibit and fossil.

In this Cretaceous scene, Leonardo calls to his mother, left. The foliage in this image – conifers in the background, ferns in the foreground – represents the types of plants found in Leonardo’s stomach. In the background, a tyrannosaur lunges at another Brachylophosaurus. Mural by Julius Csotonyi.

Dr. Bakker has been on the team that has been analyzing the fossil since 2002. According to him:

"Meeting Leonardo is a very moving, intimate experience. You will see every wrinkle and scale popping in the light, and then discover the internal organs of a creature that’s been dead for millions of years. You will leave convinced that these animals were very much alive.”

Leonardo is a young Brachylophosaurus, a two-legged, plant-eating duckbilled dinosaur, and is the first juvenile of this species ever discovered. He was approximately three or four years old when he died and would have been 20 feet long, weighing about 2,000 pounds. He was discovered on July 27, 2000 during the Judith River Foundation’s expedition in Malta.

The exhibit will also include an Ichthyosaur mummy with internal organs and four babies preserved inside and and the only mummified Triceratops skin ever found, which will also be on display for the first time.

The AP posted a short story on the exhibit, and the Great Falls Tribune did a wonderful feature this morning as well. There should be an article in the Houston Chronicle coming up soon. We'll post the link when it's live.

Monday, February 25, 2008

Discover the "X-Wing" Dinosaur - tonight on PBS

It sounds like the winning entry in Google's X prize, but "X-Wing" is actually just a very cool name for a dinosaur - also called the "Four-Winged" dinosaur and, more scientifically, the Microraptor - that sheds new light on the origins of flight.

It's got four wings. Which puts it in the running for coolest dinosaur ever. And it's the subject of a new documentary on PBS tonight, Tuesday 2/26 at 7 p.m.

If you miss it, you can watch the whole thing online starting Wednesday. Since it's a NOVA project, you can also find lots of interesting extras on the show's Web site - see fossils of the other creatures that lived alonside the Microraptor in Liaoning and experiment to figure out how microraptor used its second pair of wings. The Producer's Story gives interesting background into how they chose to tell this complicated story.

Visitors to HMNS might also remember seeing a Microraptor gui fossil and a fleshed-out model in the Liaoning diorama of Dinosaurs: Ancient Fossils, New Discoveries, a recent special exhibition from the American Museum of Natural History.

So - coolest dinosaur ever? Or just a prehistoric ostrich? Check it out tonight and let us know what you think.

Sunday, February 24, 2008

Who wouldn't love to be this kid?

8-year-old Rhys Nichols recently became the first to walk in the footsteps of a particular prehistoric plant-eater in over 160 million years. At least - he was the first one to realize it.

The 9-inch Iguanodon footprints he found are amazingly clear and well-preserved - you can check them out at the Daily Mail's story online, along with a cute pic of Rhys smiling and pointing to his clever find. Experts say that based on the size of the footprints, Rhys and his dinosaur are roughly the same size.

The story goes on to say:

"His only disappointment is that they are prints from a plant-eating dinosaur. He would rather they had been from one of the big meat-eating ones like a Tyrannosaurus Rex because they are his favourite."

With all of the extremely bright kids that come to our Museum and dream of finding dinosaurs, it is extremely cool to see one who's done it. Congratulations, Rhys - you may just have a new favorite.

Thursday, February 21, 2008

Dr. Bakker's new book: Prehistoric Monsters!

Text copyright © 2008 Dr. Robert T. Bakker
Illustrations copyright © 2008 by Luis V. Rey

Dr. Bakker's latest book is out - and it's for kids! Well, I enjoyed it qute a bit, too - so maybe we should say it's for kids, and that kid inside all of us that still geeks out over 12-foot sea scorpions and the idea of Quetzalcoatlus zooming by overhead.

Prehistoric Monsters! tells the entire story of life on Earth - from the algae-rific Precambrian to Ice Age cave paintings. And manages to do it in just 23 picture-packed pages. It's a perfect introduction to pre-history for young ones - but the incredible illustrations by Luis V. Rey are a sight to behold for anyone. This preview doesn't do it justice - but you can check it out at any bookstore.

Speaking of geeking out - Dr. Bakker also talks about our Seymour dig program on the page that covers the Permian, right next to a Dimetrodon attacking and Edaphosaurus - both of which we've found evidence of at our sites. Woot!


Text copyright © 2008 Dr. Robert T. Bakker
Illustrations copyright © 2008 by Luis V. Rey

(Thanks to Random House for allowing us to post these selections from the book.)

Wednesday, February 20, 2008

VIDEO: Nicole in 3D - CT scans of our favorite lysorophus

Recently, David wrote about the perils of being married to a paleontologist - mainly, that paleontologists tend to name things they discover after their loved ones. Sounds great! Some fossils - like Sue or Stan - are known all over the world. They're so famous, they only need one name - kind of like Cher. Who wouldn't want to be immortalized as a fossil?

Well...not every fossil is T. rex. And David's find happened to have some particularly unattractive characteritics as a species. If you missed it, check it out here and let us know what you would have done in his shoes.

In this case, David's wife now has the honor of giving her name to a particularly well-preserved lysorophus. And, the lovely people of MD Anderson were kind enough to give us a look at the inside of this fascinating fossil, through the use of the computed tomography (CT) scanning in their small animal imaging facility.


video


The cloudy red area you see in this video is the rock surrounding the fossil itself. The more defined, lighter sections show the fossil itself. As the image rotate, you can see the ribs and spine curling around. In life, it would have looked something like a pile of coiled rope, with each coil resting on the one under it. Stretched out, Nicole would have been about 18 - 20 inches long.


A Lysorophus closes in on its prey. (c) Robert T. Bakker


You can also see an vertical oval outline protruding from the main coil - it starts on the right, rolls around to the left, and then ends at the right again, it will be on the right of your screen. According to David, this is probably the skull.
Even cooler, this next video is in 3D - if you've got the red and blue glasses, this should pop right off the screen.


video



Enjoy!

Advqnced 3D Imaging and Movies courtesy of:
Luc Bidaut, PhD.
Director, Image Processing & Visualization Lab (IPVL) UT - M. D. Anderson Cancer Center Houston, TX
lbidaut [at] mdanderson.org
Computed tomography (CT) performed in the Small Animal Imaging Facility (SAIF), UT-MDACC

Thursday, February 14, 2008

Note to Eocene: You can fossilize, but you can't hide

At least not from the enthusiastic volunteers at the Houston Museum of Natural Science.
Almost every weekday, curator David Temple brings paleontology to life for the Museum's visitors. They can stand under the gaping jaws of T. rex or marvel and the sheer size of our Diplodocus - but only at David's table can visitors experience what it's like to actually find a fossil -and then try to figure out what it is.

Some days, he's got volunteers working on the sediments brought back from the Museum's dig site in Seymour. Recently, he's introduced a table full of Eocene-era sediments from the area around College Station, TX.

This week, we captured the experience on video. We hope you enjoy seeing these young minds at work as much as we do - and that you'll visit sometime soon to try this out for yourself.

video

In this video, David explains this particular project, where these fossils came from, how they ended up preserved so closely together, and how our volunteers are analyzing them.

video

Samantha, a young and very tenacious fossil hunter, shows us what she found. In the next video, David helps her identify it.


video


video

Todd is a patient, very thorough fossil hunter - here, he identifies several Eocene fossils for us, shows us how to use his tools, and lets us in on why he wants to be a paleontologist - despite David's vivid descriptions of what a hard, tedious job it can be sometimes.

Friday, February 8, 2008

David Temple - Lysorophus found!

- OR -

The perils of marriage to a paleontologist


I first met “Nicole” in a wash about 800 meters from the main quarry our team has been working in Seymour. The day was winding down, sun was shining at a raking angle, and we were all tired of sitting on lumpy, pointy rocks.

So, we took a short paleo “road trip” and in order to do some prospecting. The Doctor and Flis headed south and east, I went north and west.

Usually, this kind of contrarian behavior on my part results in the opportunity to admire everyone else’s fantastic finds. You would think that since this happens so often, it would encourage me to follow the pack. Still, it’s at least a little easier on the ego to admire everyone’s discoveries back at the vehicles, rather than at the outcrop. (Particularly after they have asked me to move some part of my body so they can retrieve or examine said fantastic find, which I have been unwittingly laying or sitting on. I have not been successful in arguing that standing, sitting, leaning, lying, on or next to a fossil, constitutes “discovery.”)

When I brought “Nicole” back to the vehicles to meet the folks, as it were, I knew the kidney-shaped rock was something interesting, as The Doctor immediately became very excited. It was a Lysorophus, a small amphibian that resembles a modern amphiuma. Faint outlines of ribs could be observed sinuously disappearing into the rock.

This was the fossil of a complete animal, still coiled in its burrow. During the late Permian it had burrowed in the mud to escape drought and wait for rains that never came.

The fossilized Nicole. You can see the ribs curling around the lower right corner.


In his excitement, the doctor called for a name. As is his habit, he suggested the name of my first girlfriend. This required some thought, as I briefly but awkwardly recalled her identity, realizing that the minimal qualification for “girlfriend” status is mutual affection.

Then – thankfully – I experienced a moment of clarity, a fast mental flash-forward, as I return home to the missus with news of the find, the name and an explanation.

“But Sweetheart, I could never name a wriggling, tiny-limbed, slime-covered amphibian that burrowed in the mud and ate by sucking - and a dead one at that – after you! I’m saving that honor for the discovery of a graceful, long-limbed and beautiful new species.”


A Lysorophus closes in on its prey. (c) Robert T. Bakker


But, this moment of clarity brought with it a mental soundtrack: Gordon Lightfoot , The Wreck of the Edmund Fitzgerald:


“Does anyone know where the love of God goes;
When the words turn the minutes to hours...”


No matter what you’ve found, naming opportunities are few and far between. So, I did the smart thing and named it after the wife, who was polite but not particularly enthusiastic, despite assurances that I had no hidden agenda in naming a dead, wriggling, tiny-limbed, slime-covered, mud-burrowing, suck-eating amphibian specimen after her – that this act was, in fact, complimentary.

Defending this claim was problematic. So, I reminded her that 292 million years ago, this thing was quite a looker…. at least to members of its species… maybe even the cutest one…and after all, it was very thin.


A X-ray of Nicole.


Hello Rock, meet Hard Place. If I ever get christening rights again, I am sticking with U.S. presidents, beloved pets or Batman villains.

I think I made the correct choice – would you have done it differently?

Nicole – the fossil, not the wife – will eventually end up freed from her burrow and on display in our new paleontology hall.

Friday, January 25, 2008

Neal Immega - What's in the coprolite?

-OR-

Thin section examination of shark coprolite from the Arroyo Formation, Witchita Group, HMNS Craddock Ranch dig site, Seymour, TX.

Today, I am doing a detailed study of a coprolite, a broken one collected about a mile from our main dig site, at a site called Spine. I selected this particular coprolite because it is not a display-grade specimen (i.e. one that might go on display at the museum) and because it shows what might be fish scales.

Let's go straight to the payoff - photographs of the thin section of the coprolite. The specimen in this picture is about ½ inch across.


A. The spiral pattern on the outside is matched by a spiral pattern inside.

B. Brown iron oxide has been precipitated on the boundaries of the layers.

C. Possible fish scale.

D. and E. Barite filled cavity. You can see the bladed crystal forms.

It looks as if the barite in cavity E has exploded the coprolite. (Try to mentally erase the cavity and see if the nodule would go back together.) Many of our fossils have been exploded by the process of caliche deposition. I have seen barite before as infillings in bones. Caliche is a mixture of calcite and gypsum deposited by groundwater evaporating at the surface. It occurs in dry areas where the rainfall is much less than the evaporation rate and Seymour certainly qualifies in the summer. It may be that we have barite caliche here also.

Almost certainly, caliche was deposited here during Permian times and then again in modern times. The caliche will make it very difficult to prepare the fossil bones. More on that in a later blog entry on thin sections of the bones.

When I started, the coprolite looked like this:

Note the spiral pattern characteristic of shark poop. It seems to be part of their anatomy, because old and modern sharks have it.

The end view makes the coprolite look like it is made of rolled up sheets. The white spots which I though were scales are really barite crystals.


After a thin section has been cut off, the end looks like this:

Note that the white bladed barite filling is now in the center. This is another suggestion that the coprolite has been exploded by the barite filling. The blue edge on the upper right is the remnants of the epoxy used to harden the specimen.

You might ask how I know that this mineral is barite. Barite, calcite and gypsum are the only common minerals that grow in bladed, white colored crystals. Gypsum is easy to test for because it is softer than your fingernail. So, I tested that by rubbing my fingernail across the white patch, and discovered that this mineral is harder than my fingernail. The white mineral also does not fizz when wet with 5% hydrochloric acid, and so it is not calcite.

So what is a thin section and how do I did I make this one? A thin section of rock is made by gluing the rock to a glass slide and then grounding it thin enough to read a newspaper through. The standard for thin sections for mineral identification is 30 microns, much less than the thickness of a piece of paper. Paleontologists are not so picky; we generally stop grinding when the section looks good.

Lets examine some other shapes to see if they are also coprolites. Flattened ovals shapes are also present, but are they coprolites? Enlarge the following picture and look at the surface and you will not see much of anything.




But the broken end of the nodule is much more interesting. You can see a round spiral in the center just like on the first specimen. The rest of the rock also shows spirals flattened into an oval shape.


We have now determined that coprolites can be found in round and oval spindle shapes, which may or may not have an external spiral pattern. A broken specimen shows a spiral structure and may or may not have been filled or exploded by caliche. There may be white barite blades present that look like fish scales. Breaking the nodule is as good as cutting a thin section (and much quicker). I have learned from this process.

So? Lets get to the real payoff. What did the sharks eat? Since these sharks have small teeth, Dr. Bakker thinks they ate small arthropods and salamanders. I cannot confirm this because I see no bone or shell fragments. It is going to take a better paleontologist than I to figure it out.

Now, how did I cut the thin section?

The process goes like this:

1. If the nodule shows the complete football shape with spiral markings on the outside, cut it in half.

2. If it is a broken specimen, grind a flat face.

3. Mix up highly fluid epoxy and stain it with a bit of blue dye.

4. Make a little tub out of aluminum foil, the size of the cut face of the specimen.

5. Put the epoxy in and immerse the specimen. The epoxy will be drawn up into the specimen by capillary pressure, hardening it. You will be able to see the added epoxy because it will be colored blue. This is a standard oil company technique.

6. Put the tub on a hot plate to make the epoxy really fluid. I use a 1:10 hardener/resin slow set epoxy specifically designed for this.

7. Heat for 30 minutes at 150 degrees F. Cool.

8. Your specimen now has an aluminum foil tub glued to its end with dark blue epoxy. Using a flat lap, grind it delicately until the blue epoxy is gone from the end.

9. Using single part epoxy, glue the specimen to a glass slide and put in the sun for 5 minutes. I use a UV setting epoxy to glue the specimen to the slide. If I used 2-part epoxy, the mixing process would introduce innumerable bubbles, spoiling the slide.

10. You now have a rock glued to the slide. To save most of the rock, I use a special jig to cut it off the slide. This leaves about 1/20 an inch of rock on the slide.

11. Grind off most of the rock with a 600-grit diamond lap plate and lots of water. This is the tricky part. STOP before it is all gone. This means that you check it frequently and stop when you can see through the rock. You have to be able to read newspaper through the rock.

Mineralogists grind their rocks to 30 microns in thickness but as a paleontologist, I grind until I can see what I want to see. I can always grind it thinner. It also does not matter very much if the slide is wedged (not even in thickness) and this can even be useful, because some things are easier to see in thicker or thinner slices of rock.