I recently went to see Jurassic Park in IMAX 3D and it was spectacular. Seeing this movie again (it has been a long time) now with my experience in ecology and evolutionary biology meant that I started noticing all the ridiculous science mumbo jumbo. Probably the first thing I noticed was the big hoopla that Dr. Grant makes early on in the movie about how dinosaurs are more closely related to birds than to modern day reptiles. He scares a little kid who calls raptors big turkeys. Clearly then, as Dr. Grant (in the movie) is a leader in his field, the dinosaurs became birds hypothesis is known, just apparently not so much by the geneticists who are trying to complete the dino DNA. No, for some untold reason they dropped in some frog DNA. But hey I can suspend my disbelief for that, it was what 1993, we knew a lot, but not THAT much (not how to make a dinosaur).
But one thing that I could not believe is the complete and utter lack of thought about ecology. John Hammond wants to create a marvelous zoological park full of dinosaurs. But, the movie only shows us his focus on the scientifically obvious part, bringing the dinos to life through careful genetic manipulations. He
“spared no expense.”
We do also get some ecology, when Dr. Sattler, the paleo-botanist talks to the park “ranger?” about the sick triceratops, and the plants it was or wasn’t eating. Of course I realize that more about how they understood the ecology of the dinosaurs is asking too much of an entertaining flick.
The movie did bring up some old thoughts I have had however, about a much more “realistic” situation: Pleistocene rewilding. This is the suggestion that megafauna similar to those that were driven to extinction in the Pleistocene epoch should be reintroduced in North America. I realize that I had a real nerd moment as I watched Jurassic Park, when I began thinking about how many of the ecological issues that are obvious in regards to bringing dinosaurs to life, would be relevant in the case of Pleistocene megafauna.
The rewilding idea has been rattling around in my head recently because of a recent National Geographic article, here, about bringing back species that have gone extinct. It reminded me of a journal article I read back in 2008 on Pleistocene rewilding. I remember reading it in a Tropical Ecology class because I had to give a brief presentation on the paper. I distinctly remember thinking “they cannot be serious” as I read it.
One of my first issues was that the authors of the paper were suggesting putting large herbivores such as elephants and carnivores (lions or tigers) into North American wilderness. Their theory was that the loss of these megafauna (mammoth, sabertooth tiger, giant ground sloth, etc) has led to a serious change in top down control and ecosystem functioning. Additionally they chose many organisms to rewild the continent with based on morphological similarity and implied ecological similarity.
It does make you wonder though. What would happen if all of a sudden we reintroduced lions and elephants to the North American plains? More importantly how would they impact the environment?
One thing that comes to my mind, while watching Jurassic Park especially, is that these megafauna existed in an entirely different environment. For the dinosaurs and the “Jurassic” plants, they had evolved to withstand a different temperature and atmospheric regime. I highly doubt that these organisms would have high fitness in today’s world. For the Pleistocene megafauna, I would expect that the species with which they had interacted were different than those around today. And in part this was the point of the authors of the rewilding papers I think, that reintroducing these species would restore some measure of diversity. But I am thinking about what I have learned about evolutionary ecology. This field has demonstrated that organisms can have a large impact on their surrounding environment, and then that impact can feedback and lead to organismal changes. My point is that these megafauna have been absent for a long time, and the landscape has changed. Reintroduced elephants and lions would not be experiencing the same environment as the mammoths and saber-tooth tigers of the Pleistocene. Thus how could we expect to predict what would happen.
Of course, that does not mean it isn’t fun to think about… speculation anyone?
Before I finish writing this I have to mention one little fun thing I noticed. As they are flying in the helicopter to the island and the two paleontologists meet Ian Malcom, the mathematician. John Hammond says to the lawyer that suggested Malcom be a part of the trip,
“I bring scientists, you bring a rock star.”
I think this is the first time I have ever heard of a mathematician being described as a “rock star,” but it would be nice to hear it more often I think.