How the user can set the energy value of a specific plant. (Screen capture from Dinosaur Island)

In England the currency of the realm is pounds sterling. In Russia it’s rubles. A lot of countries have dollars or pesos. However, the currency of Dinosaur Island is energy. Energy is what makes everything happen on the island.

As we saw earlier in What’s for dinner? there is a food chain on Dinosaur Island; and the plants are at the bottom. How much energy does a kilogram of the Nipa fern produce? In, “Sauropod Feeding and Digestive Physiology,” (Hummel and Clauss), a range of values are presented with a low of 4.7 MJ/KG (Mega Joules per Kilogram) and a high of 11.7 MJ/KG (for more information about Joules see here). The screen capture, above, is a close-up of the area where the user can adjust this value for the Nipa fern plant.

So, energy on Dinosaur Island begins with the lowly plants. What happens next?

What does your dinosaur eat? How much energy does he need? How much energy is produced when he is eaten? (Screen capture)

The plants get eaten by a dinosaur, of course. But which plants get eaten by what dinosaurs? Take a look at the screen capture from Dinosaur Island, above. Here you can select what plants each dinosaur can eat. Yes, you can also make a dinosaur either a Meat Hunter or a Meat Scavenger, too. Does that mean you could make zombie dinosaurs like a meat-eating Edmontosaurus regalis? Yes, it does, but that would be just silly.

Obviously, this ability to make a dinosaur a Meat Hunter (Predator) or a Meat Scavenger will come in very handy when paleontologists would like to test their theories about Tyrannosaurus rex as scavenger or a predator.

Users can also adjust some other very important variables for each type of dinosaur. How fast does this type of dinosaur grow? How many MJ/KG does this dinosaur need to eat everyday to survive? How much energy does this dinosaur provide when it is eaten by another dinosaur? How old does this dinosaur have to be to reproduce? And what is this dinosaur’s lifespan (assuming, of course, it doesn’t become dinner for another dinosaur)? By the way, I just read in Islands in the Cosmos: The Evolution of Life on Land by Dale Russell that, “a sample of horned dinosaur population is estimated to have sexually matured at an age of 20 and lived to an average age of 22 years, with a few exceptional individuals surviving to ~80 years.” And that is exactly why we allow the user to ‘get under the hood’ and make adjustments to these values. I’m not an expert paleontologist. I’m a computer scientist that has made a lot of models and simulations and I discovered the best thing for me to do is make available the tools that the experts can use to make the model accurate.

Update: it was announced today (July 16, 2013) that, David Burnham, preparator of vertebrate paleontology at the Biodiversity Institute at the University of Kansas. “has unearthed “smoking gun” physical proof that T. rex was indeed a predator, hunter and killer. In the Hell Creek Formation of South Dakota, Burnham and colleagues discovered the crown of a T. rex tooth lodged in the fossilized spine of a plant-eating hadrosaur that seems to have survived the attack. The team describes the find in the current issue of the Proceedings of the National Academy of Sciences.” Link to the fascinating article here.