Parrots, Dinosaurs, And Lots Of Questions
September 6th, 2009Patty
If you look at the skeletal structure of many dinosaurs, the link between them and parrots is a no-brainer. Still, it took the scientific community forever to accept this as a possibility. Down the road, it was proposed by a small group of paleontologists that some dinosaurs may have been feathered. They were treated like lepers…until fossilized feathers were found among the remains of a dinosaur previously thought to be covered in scales.
The theory has been that parrots evolved from the theropod family, which includes the infamous T-rex. However, fossilized remains of bird-like dinosaurs have been found that predate the theropods, by millions of years. Ooops. Little oversight there.
The impact theory, which tries to explain the extinction of dinosaurs, goes something like this: A Mt. Everest sized asteroid struck the earth about 65 million years ago on the Yucatan Penninsula. It left an impact crater about 180 miles in diameter, causing tsunamis three miles high and throwing debris out of our atmosphere. On it’s way through our atmosphere, the asteroid grew so hot that trees for thousands of miles burst into flame. Its impact compressed layers limestone buried in our earths surface causing a chemical reaction forcing sulphuric acid into the atmosphere which late rained down.
Many dinosaurs were incinerated on impact, others were nailed by the tsunamis and acid rain. There were a large group of dinosaurs that were far enough away from the impact zone to survive. Scientists figure they may have lasted as long as three weeks. As the skies grew dark from the debris in the atmosphere, the plants died and the plant eating dinosaurs starved to death. Once they were gone the carnivores no longer had a food source, and they died.
With all the theorizing, I have had two shining questions: 1) Where are the bodies? I understand that the incinerated ones will never be found, but what about the rest? Why is there no evidence of mass extinction? There should be thousands of the fossilized remains of these unfortunate dinosaurs in the layer of earth that marks the cretaceous-tertiary period when all of this took place. Where are they?
And 2), if dinosours were made exticts by this horrific event, how is it that we are living with their descendants?? This is the closest thing to an answer I have found. This is not news to we parrot owners, but I still feel unsatisfied.
From what I have heard/read, pre-bird theropod ancestors had already developed many avian features which were naturally selected for speed/mobility on the ground. Bipedalism, hollow bones, and light build all contribute to running on the ground as well as to flying in the air. Further features included warm-bloodedness and feathers which have the major advantage of metabolizing and preserving heat.
The way I understand it is that the majority of dinosaurs did not go extinct from the impact nor lack of food. Their bigger problem was the absence of sunlight in the short term. Large cold blooded dinosaurs depended on daily sunlight for heating their metabolism to digest food matter. The reason dinosaurs were so large was because it helped them stabilize and average out day to night fluctuations in temperature because it takes a longer time for a large body to heat or cool. If food ran out, there would have been an extinction so massive, that there would be little life beyond amoeba around today. However, fish, reptiles, amphibians, bird and mammal ancestors did survive. In some cases it was their habitat or size that was advantageous but clearly in the case of mammalian and bird ancestors, warm bloodedness was the advantage. The dying plant and animal matter of less capable creatures would naturally provide food/energy for the more capable ones.
I think the best explanation for the absence of fossils at the time of extinction is because that is actually a very very minuscule percentage of the animal sample in a span of time. The fossils we find are often hundreds of thousands if not millions of years apart when it comes to dinosaurs. The sample of fossilization you ask about would only sample the individuals killed during the few day/months surrounding the cataclysm. I know nothing about these numbers but let’s say 1 billion dinosaurs died during this impact, meanwhile there had lived hundred if not thousands of billions before this, out of which we have a few thousand specimens. My point is, odds of fossilization of the quantity of dinosaurs dying at the time of impact compared to over long periods before that are pretty small and those are so rare that it may or may not be possible to find over a very long search period.
What if in all that we forgot something, maybe just maybe birds have always been birds in the first place. And that all this talk about evolution isn’t all that it is cracked up to be. As there is huge breaks in the “theory” of evolution.
As one of those breaks is the fact that our avian friends also have air sacks, and fly. And how would one through trial and error be able to advance with an air sack for a lung? Just a thought there, as if evolution is to work it involves more then just bones and feathers….. try looking in to intelligent design for the answer. As evolution is just that a theory.
While evolution is a theory (although quite well accepted among intelligent people), “intelligent design” is pure fiction. In the scientific community it would be called a hypothesis but would require experimentation and/or evidence to support.
As for air sacs, there has actually been evidence in the bone structures of theropod dinasours that they had air sacs as well. Here is the summary of a paper directly about the topic of air sacs in avian ancestors. You can purchase the full paper or notice many more writings on this topic.
http://www.nature.com/nature/journal/v436/n7048/full/nature03716.html
Feathers, hollow bones, light build, bipedalism, warm bloodedness, and air sacs were all features of fast land based dinosaurs that were direct ancestors to birds. So rather than birds developing these features to be birds, these were existing features of land dinosaurs that just so happened to be able to use these features for flight as well which led to the evolution of an avian class.
Air sacs were useful to theropod dinosaurs in the same way that they are useful to birds. It keeps the weight down and helps oxygen exchange at the same time. Perhaps other bird like dinosaurs without air sacs were on a path to evolving flight but could not do so due to the absence of lightweight and efficient air exchange apparatus.
The only reason we hear about birds is because they exist as a successful result of natural selection. All of the failed specimens of evolution ceased to be and left no trace. Evolution is actually quite logical and understandable for any individual that removes the blindfold and wishes to learn.