Life Photo Meme: Ancient

I have lots of photos of ancient organisms, but I had to go with this picture of fossilized hadrosaur skin. First off, considering how fossils are formed, I am always impressed by seeing fossils such as these, and I am sure other feel the same way. Secondly, they offer a glimpse of what these animals may have looked like alive. Now, scientist are able to use some of these amazing fossils, notably fossilized feathers and protofeathers, and an old technique to get an even better view of what these animals looked like.

Zhang and others have reported that they are able to tell what color the dinosaurs feathers were by taking a look into the preserved parts of the cell using a scanning electron microscope. Protein pigments present in modern-day feathers and fur have unique shapes based on color, and are fairly resistant to breaking down. When these scientists looked at ancient dino (and bird) feathers, they found the same pigment shapes. Now they can tell by looking for the pigment shapes what color the feather was. What's more, by looking at the distribution of those shapes they can see if it had stripes, spots, or mottling.

I am looking forward to the new and improved museum models showing the actual colors of these amazing dinos and birds!

Cloning mammoths?!

There's a really interesting article in November's issue of Nature. The author Henry Nicholls answers the question what would it take to clone a mammoth. This is more of an intellectual exercise than an actual doable process at the moment, but only because they don't have the entire genome of the mammoth sequenced yet.

I was very impressed with the detail and clarity of the article, it brought up questions that I never considered. When making a mammoth, figuring out the genome is a relatively easy task. It's fairly easy to read the genes, but which genes go on which chromosomes? How do you then turn that huge library of letters into a set number of chromosomes, when you have no idea what that number is? And what about mitochondria? Those organelles are not built by instructions contained in the nucleus, but are transferred from mother to offspring (in rare cases, the fathers contribute some too). Nicholls does a wonderful job of laying out the problems and suggesting solutions based on research techniques that are currently being used for other (but similar) purposes.

So if you want to know what would be involved in building a mammoth, or you are just interested in learning about some cutting-edge research in cellular biology, check out this article.

Photohunter: Bright

So this was kind of a mistake photo. I was trying to get the mammoth and the building in the background, and did not take into account the light. But I like the effect.

This was taken at the La Brea Tar Pits, a truly interesting place. It is one of the most productive (in terms of numbers of ice age fossils found) tar pits in the world. It is only a few minutes drive from downtown LA, and still very much in the center of the city. The museum and associated pits is only about a block and a half wide. The park still has very active tarpits, with new tar bubbling up on the grass all the time. (Visitors are advised to stick to the sidewalks)

The pits have unearthed over 1500 dire wolves, as well as, sabertooth cats, american lions, mammoths, mastodons, ground sloths, camels, horses, short face bears, and very larger condor-like birds (to name a few). If you ever go to a museum and see a sabertooth cat or dire wolf skeleton that is very dark brown, chances are it came from La Brea (the color comes from the tar staining it). The pits are so filled, because unlike most tar pits, they were near a major body of fresh water. Migrating herds would lose members in the tar, and then the predators (like the wolves) would try to eat them and get stuck as well. This in turn attracted more predators/scavengers. Inside the museum there is a huge chunk of asphalt, with tons of bones embedded in it, taken directly from outside. It's amazing.

Invertebrate Fossil Hunting!

I went fossil hunting today and it was really neat. The site was at Silverado, and we went with the Natural History Museum of LA. This is a picture of the near vertical cliff face we were pulling fossils from, and if you look towards the bottom of the cliff, you can see the very algae filled creek you can land in if you make a miss-step.


The site was about 90 million years old, and was the shallow part of the ocean. Mostly there were a lot of shellfish, as it was the site of an oyster/clam bed.


















This was my first fossil find, an impression of a coiled ammonite. Unfortunately, I never found a whole ammonite. I am inexperienced in using a pick, so it was difficult for me to extract fossils without breaking them, and near vertical conditions of the cliff made it a little tricky to work on.

Luckily, I never ended up in the creek, although at one point I came very close. I was going for a straight ammonite near the top of the cliff and gravity took over. I first started scrambling for handholds, but after realizing there were not any, I just let myself slide down till I stopped naturally. (Basically, just above the creek)


After, that I decided that looking through the scree at the bottom of the hill was much more productive. Indeed, many of the shells had weathered out of the rock intact, so I got some nice looking specimens. Much better than trying to break them out.















So at the end of the day, I had collected what was believed to be some scaphopod shells (seen top with a modern scaphopod shell), several gastropod shells (top left in bottom picture), scallops, clams (top right in bottom picture), and some straight and coiled ammonite pieces (bottom center in bottom picture). All in all a good day!

Science 'truthiness'

While discussing with Los_cat (my hubby) whether (1) birds came from dinosaurs, (2) shared a common ancestor with dinosaurs, or (3) shared a common ancestor with crocodilians (because of a similar inner ear structure, but this is most likely due to convergence), I decided that The Tick was only partly right when he called science a two headed beast. In fact, science is a many-headed beast which bickers with itself, but stems from a common body of knowledge.

Eventually, there will come a consensus on which of the three hypothesis are correct as the body gets bigger, and more evidence is examined. Personally, I'd go with number one at this point, based on the number of dinosaurs with feathers, wishbones, and front limbs that folded back like birds (Maniraptorans especially). Also, you can't really tell a dinosaur from a early bird without the feathers (archaeopteryx was initially classified as a dino until they found one with feathers). Finally most early birds showed up 45 million years after dinosaurs were established. But if they find older birds, than I may have to revise my position to two.

(Picture: Microraptor, a dromaeosaurid dinosaur fossil, from Liaoning, China on tour in 'Dinosaurs: Ancient Fossils, New Discoveries')

Cool thing: Whale fossils

What better way to celebrate winter solstice than by visiting some great tidepools? We headed out to the tidepools and stopped by the Cabrillo Aquarium to check out the cool fossil finds that had just been discovered.

The week before, one of the directors of the aquarium was visiting the tidepools when he noticed these really cool fossil whale remains.

This is a shot of the rostrum. The two center lines that are close together are the upper jaw, while the bottom line is one half of the lower jaw.

Here's the neat part. This may be a cast of the inside of the brain case. The knob on the back end may be the foramen magnum.

Finally, a close shot of the fossilized bone. You can see the two layers of bone, the lighter compact bone (or cortical bone) and the darker, more porous spongy bone (or cancellous bone).

What a cool tidepool find!