The La Brea Tar Pits in California are known for saber-toothed cats and mastodons but they also have insects. Recent examination of fossil leafcutter bee nest cells, led by Anna Holden of Natural History Museum of Los Angeles County and colleagues, reveal insights into the habitat and climate at the La Brea Tar Pits toward the last Ice Age.
Most people think of desert sand when they envision Saudi Arabia. The country’s geography is dominated by the Arabian Desert. There are virtually no rivers or lakes, and daytime temperatures can reach 129 degrees. Dinosaur fossils are rare there. Only a handful a fossilized bones have ever been found.
But an international team of scientists has just announced the first formally identified dinosaur fossils from Saudi Arabia. Several bones from the tail of a huge Brontosaurus-like sauropod dinosaur have been identified. Judging from the size of the bones, the animal may have been up to 20 meters in length.
The paleontologists (the scientists who study prehistoric life) have also identified a tooth from a meat-eating theropod dinosaur. Although distantly related to big Tyrannosaurus Rex, the tooth probably came from a type of dinosaur only about six meters long. The team found the bones in the northwestern part of the country along the coast of the Red Sea.
The teeth and bones are approximately 72 million years old. Now that paleontologists know where to look, future discoveries are more more likely. “The hardest fossil to find is the first one,” said Dr. Tom Rich, of Australia’s Museum Victoria.
It’s All in the Lingo
Understanding the classification of different dinosaurs can be confusing, but for budding paleontologists who want to “dig in” a little bit, the fossils finds discussed in this article are a great place to start.
To get a handle on where the extinct animals discussed above fit in, envision a dinosaur family tree that develops two main divisions.
One of the two main divisions is termed Saurischian. All the dinosaurs in the saurischian line developed from a common ancestor and share the same kind of hip structure. In fact, the word “saurischian” actually means “lizard-hipped.”
Within the Saurischian line, there are two major groups.
One of these groups is called the Theropods and includes predators such as the famous T-Rex.
The other group is called the Sauropods and includes plant-eaters like Brontosaurus.
So, when scientists say they have found a tooth from a theropod, or tail bones from a sauropod, they are being specific. They could have said the tooth came from a saurischian or simply from a dinosaur and still have been correct. But those terms are less specific.
How big is too big when it comes to walking? That is exactly the question asked by a team of scientists studying the skeleton of the biggest animal to ever walk the surface of the earth. The Argentinosaurus — a dinosaur named after the country of Argentina, where it was found – was so big some people have questioned whether it could have even been able to walk.
The dinosaur skeleton studied by paleontologists at the Carmen Funes museum in Neuquén, Argentina, suggests an animal that would have measured more than 40 meters and weighed around 80 tons. The Argentinosaurus lived around 94 million years ago.
A team from the University of Manchester in England worked with researchers in Argentina to try to discover once and for all whether Argentinosaurus would have been too big to walk. If not, then scientists would have to conclude that the skeleton – which was recreated from a partial set of fossilized bones – was somehow wrong in scale or design.
The scientists scanned the skeleton to build a computer model. Then, using an advanced computer modeling technique they recreated its walking and running movements and tested its locomotion ability.
“If you want to work out how dinosaurs walked, the best approach is computer simulation. This is the only way of bringing together all the different strands of information we have on this dinosaur, so we can reconstruct how it once moved,” Dr. Bill Sellers, lead researcher on the project, said.
The verdict? Houston, we have liftoff! Or, at least, locomotion. The simulation shows that Argentinosaurus would have reached speeds just over 5 miles per hour. You can watch it yourself in the video below.
Dr. Sellers said the research is important for understanding more about muscle-skeleton systems. “All vertebrates from humans to fish share the same basic muscles, bones and joints,” he said. “Argentinosaurus is the biggest animal that ever walked on the surface of the earth and understanding how it did this will tell us a lot about the maximum performance of the vertebrate musculoskeletal system.”
Stay tuned, because The University of Manchester team now plans to use the method to recreate the steps of other dinosaurs including Triceratops, Brachiosaurus and T. rex.
If you’ve ever handled a freshly cut Christmas tree or spent an afternoon climbing a neighborhood pine, you know that trees can get pretty sappy. Part of the healing process for a tree that loses a limb or gets a cut in its bark is to fill in the damaged area with sticky, gooey, sappy resin.
This helps the tree form something like a scab. The scab keeps out bad things (like germs) and keeps in good things (like water).
While this excellent healing process is great for the tree, it can be pretty crummy for insects that come along and get stuck in the sap.
But that is not the end of the story.
Fast forward a few million years, and the scientist of today can find well-preserved insect fossils still in the sappy resin. By this time the resin has turned into a fossil itself, called amber.
Researchers have found all kinds of ancient insects in amber, and have found frogs, flowers, lizards, even the bones of small mammals and animal hair. For scientists studying creatures that are mostly long gone, amber adds up to a real treasure trove.
Recently, scientists at Oregon State University have been studying a rare amber fossil that trapped a spider just as it was attacking a wasp that had just gotten stuck in the spider’s web. The spider was moving in for the kill when resin covered the web, freezing them both for all time. Talk about your sticky situations.
Fossil: the remains or impression of something that was alive in prehistoric times, now preserved in rock
Resin: a thick substance that flows from some types of pine trees
Amber: fossilized resin
Mammal: warm-blooded animals with hair or fur that fed their young milk