What caused the Triassic-Permian extinction to allow dinosaurs to develop?

Answer:
There have been lots of proposed causes, but new data from China is providing some new clues. The critical information is time-how much time was involved in the extinctions? Was it sudden or gradual? It used to be thought that a lot of time was involved, perhaps hundreds of thousands of years or even a million years. But a new and very complete sequence of rocks in China that have been dated and include lots of fossils is showing that the extinction was nearly as sudden as that at the end of the dinosaur era. So it may have been a large asteroid or some other environmental catastrophe that caused an avalanche of extinctions. - Paul

What is the smallest dinosaur you have found?
How small was it? What did you name it?

Answer:
The smallest dinosaur that I ever found was a hatchling psittacosaur or "parrot-beaked" dinosaur. The skull was the smaller than a quarter. It already had a name, Psittacosaurus. Eoraptor is the smallest dinosaur that I named from an expedition of mine. It's about 3 feet long. Now, we have just found a dinosaur skeleton slightly smaller than Eoraptor. What shall we name it? Hmmmmmm, we will have to wait until we clean it off in the lab and get a good look at it.

How long did it take for the nigersaurus to hatch an egg? How many would they lay at a time?

Answer:
We now know that some dinosaurs brooded (sat on their nests) like birds, because we have found skeletons in that position, crouched on top of a nest of eggs. Interestingly, these dinosaurs (namely Oviraptor and Troodon), are some of the closest relatives of birds. Other dinosaurs probably didn't brood, which is a behavior peculiar to most birds and unknown among living reptiles. This is true of the sauropods, or long-necked dinosaurs, like Nigersaurus. They laid their eggs in a pile, probably all at once like living reptiles, and left them to hatch on their own. Sauropod nests are like other dinosaur nests, which have anywhere from 10 to 30 eggs. How long it took to hatch is unknown. However, it was surely shorter than a year and probably less than two months.

Trying to find information from other questions already asked, how many pieces from the nigersaurus have you found?

Answer:
We have now found most of the skeleton. Of course, we need to clean the skeletons that we have collected to know for sure, but it seems as though we are missing only a few bones in the skull, tail, back and hind foot. Next to Jobaria, it will soon become one of the best-known sauropods of the Mesozoic!

In your opinion, how did the dinosaurs die out on Earth?

Answer:
An asteroid impact and its aftermath and climate change were the two main factors, the first being the strongest. A worldwide drop in sea level caused the climate to become more seasonal (hot-cold) on land.

Parent Question: In the movie Jurassic Park, the paleontologist found droppings. Examination of the feces told the humans a great deal about the dinosaur. have you found petrified droppings to examine? What have they told you?

Answer:
We have found petrified droppings here in Niger, although none from dinosaurs. They have come from fish or crocodiles. To learn something more from them, we would need to section them. They are now petrified and as hard as stone, but in section sometimes you can see bone or plant bits under the microscope. The biggest "blooper" in the film was showing horned dinosaur doo doo as a huge steaming pile four feet high. That is ridiculous. No known animal leaves droppings like that, not even an elephant. I guess the filmmakers thought that only a mountain-sized pile would be appropriate for a dinosaur. Most dinosaur droppings don't look all that different from that of a cow, but I am sure that a specialist would observe more differences. Keep in mind that a good naturalist on a trail (or for that matter any good nomad in the Sahara) can tell apart many different mammal species on the basis of the shape, size, texture and color of droppings.

Have you found any fossils showing the imprint of dinosaur skin? Have you found any organs of dinosaurs? How do scientists know the skin color of dinosaurs, or are they guessing? How do they know the sounds that they made?

Answer:
We did not find any skin or organ impressions. That is not unusual-impressions are quite rare. We probably will never know the color of dinosaur skin, because the actual skin with scales that would have the pigment (that is, the actual chemicals that make the color) are not preserved. We suspect that dinosaurs made many different kinds of noises based on living animals. Nearly all animals can at least hiss. Many have organs in the throat that make special sounds. We have a "larynx" that makes the sounds of speech. Songbirds have a something similar. Dinosaurs may have had something in their throats to make special sounds, but we will never hear those sounds again. - Paul

Do the different varieties of dinosaurs have a different total number of bones or are the bones just bigger in some? If so, which varieties have the most bones? If not, what is the total number of bones in a dinosaur skeleton?

Answer:
The number of bones in the skeleton of a dinosaur is roughly the same, if you are excluding special bones like armor plates. Every dinosaur has two femora (thigh bones) and three bones on each side of the pelvis, for example. However, the number of vertebrae in the neck and tail often varies considerably. A typical dinosaur tail consists of about 40 to 45 vertebrae, but duck-billed dinosaurs usually have 60. The number of bones in an average dinosaur skeleton is over 200 - often around 230 separate bones. -Paul

Did dinosaurs have finger and toe nails?

Answer:
You bet! We see the attachment grooves for the nails on the last bone or claw on dinosaur hands and feet. Plant-eaters typically had flatter hoof-shaped nails, whereas meat-eaters had sharper curved claws. Although the actual nails are only rarely preserved, we can see that shape of the nails in the footprints that they made when they were alive. - Paul

Have you discovered any Nigerian food that you really like? Will you be able to continue eating it When you get home?

Answer:
People here eat mostly rice, couscous, millet along with goat, mutton or beef. Sometimes they make slightly spicy sauces to go on top of rice or couscous. Right at the top of our list would be brochette (grilled beef on skewers) with fries and sprinkled with "yazi yazi" a spicy peppery-powder. Down here, in the capital, we are right along the Niger river and one of our favorite dishes is grilled fish - usually served with rice and sauce, or fries. We will probably try to bring some yazi yazi home with us since we haven't been able to find it in Chicago. -Gabrielle

Has your dog, Dino, gotten in the way? Has he ever tried to bury the bones you have excavated?

Answer:
Our dog, Dino, has gotten in the way many, many times. However, I am happy to say that amongst Dino's list of great exploits, you cannot find "burying bones we have already excavated." Dino is extra fond of chewing on the edges of the plaster jackets - something Paul is less than thrilled about. Dino happens to be very good at digging, but we have never quite been able to get him to dig on command, so he isn't very useful in the field. Typically Dino sleeps all day or lounges around. What is better to do in the heat?! That means he has lots of energy when we come back from a day of work, and, unfortunately, lots of energy to stay awake at night barking at anything that moves. -Gabrielle

Parent Question: What are the educational requirements to becoming a paleontologist?

Answer:
Usually all special training occurs in graduate school after college. That is surprising to most people who ask that question. You need to have a good background in general science first.

Good writing skills and even artistic abilities can also be extremely helpful. The study of fossils is sort of like icing on the cake! I only had two courses specifically on fossils before I entered graduate school knowing then that I wanted to be a paleotologist. I took a course on the human fossil record and another on invertebrate paleontology (mostly about shells and other common marine fossils) when I was in college at Northern Illinois University. The fact of the matter is that there are many basic courses in science that you really need, like chemistry and statistics or geology.

Any special experiences or classes that you have the opportunity to take are a great help, but they are not truly essential. The only truly essential thing is that you are able to do very well in college, take a variety of courses, and that you like to do research-that is, you like to discover things and write about those discoveries in research reports or papers. - Paul

Were you restless, anticipating the first days' dig? (Kenneth L. - 4th grade)

Answer:
You bet! I was incredibly restless because of the late arrival of our supplies from the cargo boat. We were so restless we decided to go into the desert to begin work with "leftover" equipment and supplies from the last expedition that we had left behind. The areas that we needed to search are very large, as are some of the dinosaur skeletons, if you are lucky enough to find them.

How is it possible for the dinosaur to lay undiscovered until the year 2000?

Answer:
The desert is a very, very large place. The areas in the desert that have rocks of dinosaur age are hundreds of miles across in either direction, with no roads. Imagine searching a place the size of Illinois! You have a map and a few notes published 50 years ago by the last guy who came to look - on camelback! Some of the bones are difficult to see - you might walk right by, or even step on them without noticing. My best find of the season occurred at the very end - a huge skeleton of a new long-necked dinosaur. I found a few bones poking out of the ground 50 feet from a dinosaur skull that I was collecting. I was waiting for the plaster to dry on the skull, and thought I might just walk around a little! We were all in the same area for days and hadn't seen this skeleton, because only a few bones were poking above the surface. So, I think you might be able to see how there are still many discoveries to be made, even after the 2000 Expedition.

How many dinosaurs do you think are waiting to be discovered?

Answer:
There are probably at least 100 dinosaurs that might be named in the next 20 years. Dinosaurs are being named at a rate of about 6 each year. True, most are not as complete or different at the ones that we are finding and naming from Africa. But they deserve new names, as long as it is clear that they are different from all other named species. More than half of existing dinosaur names were coined in the last 30 years, because there are more people looking and more places interested in displaying their bones.

If the T-Rex was the scariest dinosaur, how does Suchomimous and Jobaria compare to it? (Parent)

Answer:
I don't know that T. rex is the scariest! With T. rex, at least you wouldn't have to worry too much about its tiny forelimbs. Suchomimus was nearly as large but had powerful four-foot-long forelimbs with a 16 inch thumb claw. Spinosaurus, a close relative of Suchomimus, seems to have grown to a size even larger than T. rex. Jobaria, of course, was enormous-70 feet long as an adult. You need to be extremely careful around any large animal, even plant eaters. If an elephant gets mad, watch out! On an open plain, you would not survive against a plant-eating elephant. It would easily run you down, even though it cannot gallop. I suppose the same would be true of Jobaria.

I love turtles and finding them in the woods and creeks. How similar is your work to finding turtles? (David R. 6th grade)

Answer:
It is very similar. You need to have good eyes to find turtles in rivers. You could easily paddle down a river and not see a turtle on a rock, or only see the ripples after it dived under. The same is true of fossils, except that they don't run away! By the way, on this expedition we found lots of fossil turtles, including some new species.

We are studying "Did Dinosaurs Eat Spinach?" Did dinosaurs eat foliage similar to spinach?

Answer:
Spinach is a flowering plant, technically an "angiosperm." Most of the dinosaurs that we are digging up lived when this kind of plant was rare. Back then, ferns and evergreen plants were the most common. Now spinach plants and their close relatives are very common in most warm environments.