Monday, January 9, 2012

Dinosaurs: The Fascination

The mother and infant Tyrannosaurus from Walking with Dinosaurs: The Live Experience

Dinosaurs: They've haunted our imaginations since we first laid eyes on their skeletons in our local museum. Creatures of tremendous size, strength, and power that once lived and breathed on a long lost Earth. So far from understanding them or their lives, yet so close that we can just reach out and touch them.

People sometimes ask me, why are people so fascinated with dinosaurs? Why are we so attracted to them? Why are we so curious about them? At first I wasn’t able to answer these questions myself. What's the reason? Why am I the Dino nerd I am? Well, to answer these questions we might need to go and see what a dinosaur is in the first place.

Dinosaurs were named by Sir Richard Owen in 1842, and roughly translate to “Terrible Lizards.” Not actually true lizards, they represent a distinct group of reptiles called Archosaurs which includes Crocodilians and kin, Pterosaurs, protodinosaurs, and modern birds. Archosaurs are arguably the most successful group of land vertebrates on the planet, ranging in size and diversity to take on a number of bizarre forms, typically taking body designs to the extreme, and benefiting from being odd.

Dinosaurs were among the most diverse and successful of this group, ranging in size and shape from small feathered predators a little over a foot long, to 100 ft. giants that make entire herds of elephants look tiny. One thing that separates them from other groups of reptiles and many other types of Archosaurs is the fact that unlike other reptiles with sprawling legs like a lizard, dinosaurs had their legs directly underneath their body in an erect form, similar to modern day mammals. This allowed them to support more massive bodies and more active lifestyles than other animals at the time. The ancestors of dinosaurs had erect legs even before the first mammals evolved the trait --they invented the leg design.

Along with being the first animals with erect limbs, they also evolved more complex ways of living. It was originally thought that dinosaurs were ectothermic (cold-blooded) and similar to most reptiles in their metabolic rate.  However, in 1968 a series of papers by Dr. Bob Bakker started citing more and more evidence for endothermy (warm-blooded) in dinosaurs, and is nowadays widely accepted in the paleontological world. A group of dinosaurs in particular, called Theropods, evolved to be active fast-moving predators, something that typically is only seen in endothermic animals.

Other evolutionary advantages soon followed, along with being endothermic and having an erect leg posture, they also evolved many other distinct features to adapt to their world. Many Ornithischians evolved the ability to chew their food, something rarely seen in reptiles, which helps with speeding up digestion. Saurischians on the other hand evolved a highly advanced method of breathing by using air sacs connected to their lungs, a method very similar to that of birds.

Dinosaurs were extremely successful even since their origins in the Triassic, they were the most successful group of land vertebrates of their time, and were far more successful than all modern-day mammals. More dinosaurs are discovered and named every few weeks, and amazingly, we’ve only discovered a little more than 2% of all the dinosaur species to ever have ever lived on this planet. But the mystery still remains: Why if they were so successful did they go extinct?

The answer to this question is very uncertain.  Maybe it was increased volcanic activity, or possibly sea levels dropped dramatically, or maybe even a deadly virus was among them. At the moment the most widely accepted theory is that a meteorite smashed into the Gulf of Mexico and caused their extinction, but there is still much to debate about.

All we know for certain is that dinosaurs are gone, leaving only their descendants, the birds, to fill our skies overhead. Maybe that’s the reason why we’re so keen to learn about them. Dinosaurs were some of the most amazing and diverse creatures to ever live on our planet, and they’re gone. But of course, we should in a way be thankful, for without them disappearing, we would never have appeared on this planet. The dinosaurs reached a sad end, and as with all creatures, we will one day follow.

The fact that such powerful creatures ruled their planet for so long, it somewhat reflects upon ourselves. Dinosaurs were the kings and queens of the planet, and lived in a kingdom that was all their own, only shared by some terrestrial crocodiles. We are the same. We humans are the kings and queens of our planet right now. We live in a time of plenty and are the dominant creature on the Earth, but for how long will our kingdom last? Will we go the same way as the dinosaurs? Most likely, yes.  No creature, no matter how powerful, can survive forever, and dinosaurs prove that.

That’s the reason why I think we’re so fascinated by dinosaurs. We Homo sapiens have only existed for the past few hundred thousand years, while dinosaurs have ruled the earth for a total of 165 million years, and continue to thrive today in the form of birds. But how long do humans have left? Will we continue to thrive onwards into the future, or is our time on planet Earth quickly running out? Only time will tell.

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