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Do you have a question about Dinosaurs, Expeditions, or Paleontology in general? Ask us!

Q: What caused the extinction of the Super Croc, was it some type of environmental stressor and resulting events?
A: As is often the case in science, especially in paleontology, it is difficult to knowwith certainty why something happens. When dealing with events that happened long ago, it becomes very hard to reconstruct the puzzle because we have a fairly imperfect picture not only of the extinct species themselves but also of the environment at that time. Super Croc is only known from a very brief portion of time in very small region of our planet. Arguably, this species, or a near relative, may have also been present in Brazil, but there is scanty evidence for this.

Super Croc lived during the Early Cretaceous, and as far as is known for this region, at this time, there were no considerable extinction events of which to speak. Many hypotheses could portray what happened, but unfortunately, as you even indicated in your email, it is very difficult to find a straightforward explanation. There could have been changes in the environment that led to the ultimate demise of Super Croc. For instance, if this region became more arid due to climate change or shifting of the large river systems present in this area because of geologic processes, the amount of vegetation could have been considerably reduced. Such a change in the vegetation might mean that there is no longer enough plant material to support large terrestrial herbivores. And without these herbivores, it would have been difficult for large predators to survive. Even though Super Croc lived in the water and could have fed on some of the pretty large fish known from this area, it would probably have been very important for this animal to eat some of these large prey (even today, you can see crocodiles take down thirsty herbivores in National Geographic specials...just think of Super Croc eating iguanidontid dinosaurs instead of wildebeest!).

Likewise, with a change in the amount of water in the area, Super Croc's environment could simply have disappeared. As you will see on the Project Exploration website (visit the Niger 2000 expedition webpage), an archeological site was discovered on the last expedition to Niger. This site is now located in the middle of dune fields, but we found remains of very large fish, crocodiles, large snakes, and even hippos or rhinos. Today, an environment that is able to support such a diverse group of animals cannot be found for within hundreds of miles of that site, yet the site is only a few thousand years old! Climate change can occur very rapidly.

Q: How did the present day crocodillian survive while the Super Croc became extinct? I am not sure what the exact adaptations were.
A: When considering why modern crocodiles survived and Super Croc went extinct, it is important to remember that this is largely a random process. While there are certainly adaptations that are important for the survival of a species, these do not guarantee that a species will survive indefinitely! Maybe Super Croc's large size was an "adaptation" for being able to sucessfully attack some of the extremely large terrestrial herbivores (like the sauropod dinosaurs) available in this region. But then again, if these large herbivores were to disappear because of local climate change, this same large size (and all of its related metabolic needs!) could have done this species in.
I hope that all of this provides an idea of how unpredictable life, evolution, and extinction are. I also hope it conveys some of the difficulty that paleontologists also have as they interpret what happened in the past. Paleontologists often need some really good evidence in order to make any general conclusions about these events that occurred so long ago!

Q: What are the academic requirements to be a paleontologist?
A: Most professional paleontologists have completed a PhD in a field such as biology, geology, anatomy, paleontology, etc. This means that they also finished a college degree. Coursework that is important to paleontologists are those in biology and geology. Understanding both the life of an animal and its death and subsequent fossilization are important when studying fossils.

Q: Who hires a paleontologist? In my report I wrote down that geology departments of universities, museums of natural history, and specialized organizations hire paleontologists. Is that right?
A: Yup, that's right. I would just also add biology departments to your list, as well as medical schools. Because of their detailed knowledge of anatomy, paleontologists can often be found teaching anatomy to medical students.

Q: I've been to Africa six times (with my Mom, who is currently finishing her MD). Any chance I could hook up with you guys sometime!!?
A: You will have to take this up with Dr. Sereno. Visitors are not common on trips, as it is largely a problem of supplies and logistics.

Q: How do you think paleontology has affected history?
A: Paleontology has given people a view into a past in which there were no people. In fact it gives us a picture of our world that doesn't seem like our world at all, and this is probably why so many people are fascinated by paleontology. Studying organisms from the past helps us reconstruct what has happened to life over time. It gives us an appreciation of what we refer to as "deep time", and also helps us understand that changes that our planet has undergone. It adds another dimension, time, to our understanding of the present world.

Q: How many years of college does it take to become an paleontologist
A: You need to go to college for four years and then also go to graduate school where you can devote all of your time to studying a particular aspect of paleontology (dinosaurs, trilobites, mammals, etc). Then once you've completed graduate school, you can go on to get a job at a university of museum where you can carry out your own research and teach other people how to be a paleontologist.

Q: What is the most difficult thing about paleontology?
A: Doing fieldwork, looking for and collecting fossils takes a LOT of hard work, but in the end it's worth it. Perhaps the most difficult part is figuring out exactly what the fossil you find IS. To do this, you have to know not only a lot about anatomy, but you have to know a lot about many different types of animal. This will allow you to accurately identify the bone of the type of animal that you have found.

Q: On average how long do you stay at one site?
A: How long we spend at a particular site depends upon one, the size of the specimen(s), two, the toughness of the rock that the specimen is in, and three, how many people are working on the site. We find specimens of all different sizes and shapes, so every site is different. On average we probably spend a couple days on a site, but sometimes it could be as little as a couple of hours (for if we find just one isolated bone) or a couple of weeks (for instance if we find a big sauropod dinosaur (a long-necked type like Apatosaurus or Brachiosaurus )