The Truth About Dinosaurs

By Romana Annette 03/08/2008

A famous poem starts:

Behold the mighty dinosaur,
Famous in prehistoric lore,

Not only for his power and strength
But for his intellectual length.

The poem goes on to imply that dinosaurs were not very smart.  The word dinosaur has come to also mean something that is outdated, even currently useless.  Ever since the first fossils were discovered 165 years ago, we have been fascinated by dinosaurs.  Misconceptions about these long lost creatures abound, and much information has become urban legend.  However, most of what we know is just from fossilized bones; there have been little in the way of fossilized tissues, skin, and organs.  Also, we have discovered only a fraction of the massive total of all dinosaur species that ever lived.  Fossilization is a very rare event, which depends on random circumstances, as well as the number of members within a given species.  As more of the planet has been opened up to exploration, the number of fossil find has been going up exponentially.  

Dinosaurs dominated the land for 155 million years.  They were enormously successful.  However, they had to share the planet with a host of other vertebrate species [Appendix A.]  Other reptiles dominated the sea and the air.  There may briefly have been a flying dinosaur, before that species evolved into birds.

I will now deal with many misconceptions:

Dinosaurs Were Not Adaptable.
This idea is not true; dinosaurs prospered because they were extremely adaptable.  The reasons are as follow:

·      Dinosaurs were agile and evolved a bodies that had efficient physical movement.

·      Dinosaurs likely had a super efficient respiratory system.

·      Dinosaurs often responded to threats and competition by evolving newer and bigger versions.

·      Dinosaurs were able to colonize harsh environments, especially the hot, arid areas of the Pangea super-continent.

·      There is accumulative evidence that most dinosaurs practiced parental care, as well as maintaining some kind of family relationships.

Dinosaurs Oppressed Mammals.
This is only technically true, since true mammals evolved a few million years after the appearance of the first dinosaurs.  However, mammal-like reptiles dominated the Earth long before the first dinosaurs evolved.  Dinosaurs had a more efficient design that evolved variations far faster than that of mammal-like reptiles.  Once, one out of every two land animals was a variation of the mammal-like Lystrosaur.  When the Lystrosaurs died out due to lack of diversity, dinosaurs simply evolved to fill the vacuum.  Those mammals who successfully shared their environment with dinosaurs did so by becoming nocturnal, since most dinosaurs were likely diurnal.  Mammals simply could not develop a strategy of adaptability to match the emergent arms race of dinosaurs, while the dinosaurs were existent.

Dinosaurs Were Stupid.
While dinosaurs may not have been super intelligent by modern standards, they were smart enough to survive and prosper.  The story that dinosaurs needed a second brain in their rump to function was simply not true.  Some of the later, agile carnivores may have been exceedingly intelligent.  We do not know what level of intelligence they may have possessed, or how it compared to that of human beings.  All we know is that their descendents, birds, have more white matter than gray matter in their brains, while mammals have more gray matter than white matter.  White matter seems to control more instinctive behavior, while gray matter seems to control high level emotions such as compassion and caring.

Mammals were Superior to Dinosaurs.
This is not true; it is just human bias.  Mammals and dinosaurs were separate orders, each with its advantages and disadvantages.  Mammals developed hair for insulation, while dinosaurs developed feathery materials.  While many dinosaurs did grow huge, there were also many dinosaur species the size of small mammals.  Mammals, birds, and dinosaurs do share one special feature not found in other animals: babies were born disproportioned in relation to adults, which would induce adults to care for them.

Carnivorous Dinosaurs were Monsters.
Unlike in movies, carnivorous dinosaurs did not have an agenda of death and destruction.  They would not have been bullet-proof; rather, they were somewhat fragile and easily injured.  While they were opportunistic hunters, they probably ate carrion most of the time.  Like most carnivores, when their stomachs were full, they spent their time doing others things, such as lounging around, raising young, showing off their colors, testing the hierarchical dominance, and pursuing mates.  Their lives were not easy, and they did not live very long.  For instance, the best-preserved Tyrannosaurus, Sue, was only 29 years old when she died.

Herbivorous Dinosaurs were Cute and Docile.
This is not true; television and movies promote this erroneous view.  Remember, in Africa, the most dangerous animal is the herbivorous hippopotamus.  During their long lives, the largest herbivores possibly maimed or even killed many of the largest carnivores in self-defense.  These animals had size and weight on their side.  In the movie Jurassic Park, the scene where the scientists walk into a herd of Brachiosaurs is the most preposterous kind of fiction.  Brachiosaurs would likely not have tolerated human interlopers any more than do elephants today.

A Cataclysmic Asteroid killed off the Dinosaurs.
This idea is far from final.  One scientist claims the asteroid struck 300,000 years before the dinosaurs died off.  No one has any statistics for extinction curves (member counts over time) for any prehistoric species.  When member counts become low for a species, the fossil record essentially vanishes.  During their long reign, countless species of dinosaurs appeared and then became extinct.  Robert Bakker, the famous paleontologist, says the ultimate reason for the extinction of any species is the failure to produce any more babies that grew to reproductive age.  Isolated pockets of dinosaurs could have survived a few millions years after the major extinction event.  We do not know when the very last dinosaur died.

Dinosaurs Might Survive on some Remote Island
It is one thing to surmise that isolated pockets of dinosaurs survived the major extinction for a few million years, but it is quite another to hope that they might still survive in some remote jungle or on a distant island.  Dinosaurs prospered and evolved because each species consisted of an enormous number of individuals.  If dinosaurs still survived anywhere, they would have to be quite evident, instead of only appearing in blurry photos and local legends.

We might be able to Clone Dinosaurs Someday.
The answer is no!  While cloning a 20,000 year-old mammoth might be a possibility, finding viable dinosaur DNA is simply impossible; DNA cannot survive for 60 million years, not even inside a bug encased in amber.  The dinosaurs are gone forever.  They were not simply sets of exotic bones; they had emergent qualities and led subjective lives filled interactive events about which we can only guess.

Birds are the Direct Dinosaurs Descendents.
This is on partially true, in so much as birds are descended from one type of a small carnivorous dinosaur that lived 120 million years ago.  However, the overwhelming majority of dinosaur species became totally extinct.  Birds share so many anatomical similarities with dinosaurs that their ancestry cannot be dismissed.  Also, birds that lived during the Cretaceous still had teeth, which is what one would have expected.  Evolution has eliminated the occurrence of teeth in modern birds.

Appendix A – Major Vertebrate Groups

Dinosaurs did not have the planet all to themselves.  Human beings, as well as dinosaurs, evolved from diverse species of reptiles.  Reptiles evolved from amphibians, and amphibians evolved from lobe-finned fish.  The earliest vertebrates evolved legs, which they used to walk on the sea floor.  Fins evolved after legs, so the genetic encoding for legs is quite ancient.

The following table denotes the major groups of land vertebrates: