Higher Oxygen & Air Pressure: The Necessities
Both evolutionists and many creationists believe the earth, at one time, had higher oxygen levels then it does today. Many evolutionists, in fact, propose that low levels of oxygen led to the extinction of the dinosaurs (coupled with other factors). The reasons for this belief are abundant, and some of them we will touch upon.
The timetables for which these environmental altering events occurred, however, are vastly different between the evolutionist and creationist. The former places such changes during the periods of the Triassic, Jurassic, etc., millions of years ago. The latter places the changes during one cataclysmic event, with that event having occurred only some thousands of years ago. The two perspectives are polar opposites, and yet, share a bit of common ground.
For one, both see that higher oxygen levels and great air pressure are necessities. Realize that when we use the word both, we are not speaking of both camps entirely. There are obviously differing views.
Why are such conditions necessities? Here are some reasons.
Higher Oxygen: Evidence & Reasons
Big Bugs & Research At ASU
Evolutionary scientists know full-well that dragonflies as large as hawks and cockroaches big enough to take on house cats thrived during the Paleozoic era (245-570 million years ago, according to their timescale). One physiologist, John Harrison, has been particularly fascinated with such creatures. Harrison is a professor of biology at Arizona State University, and wanted to know why insects of long ago grew to be so large. He and his colleagues believed the answer to be in how insects breathe, and they are busy studying how the respiratory physiology of modern insects affects their body size.
Air breathing animals breathe with lungs. Insects, rather than lungs, breathe with a network of tiny tubes called tracheae. Air enters the tubes through a row of holes along an insect’s abdomen, and then diffuses down the blind-ended tracheae. In terms of the subject at hand, it is here where the rubber meets the road, because the distance oxygen can travel down the tracheae is dependant upon its concentration in the air. Theoretically, then, if atmospheric oxygen is doubled, it will make it twice as far. If an insect has a longer trachea, therefore, one should expect that the insect will need higher oxygen to breathe.
The question is, can all this be tested? In an attempt to do just that, Harrison studied and continues to study some of the larger insects of our day in his ASU laboratory; namely grasshoppers and dragonflies. What he has found is revealing. The insects’ activity is affected by the amount of oxygen in the atmosphere, and just as the theory predicts, the effect is more pronounced in the largest specimens. The biggest bugs have the longest trachea, and therefore need the most oxygen.
For the remaining skeptics, there is one last test that should be made ... and has been made. If the theory be true, then smaller insects with shorter trachea should be able to deliver adequate oxygen to the tissues even in a low-oxygen atmosphere, and this difference should be most obvious when the smaller and larger insects are forced to engage in oxygen consuming activity, such as flying or jumping.
Simply put, this is exactly what Harrison has seen in his laboratory, and not with different kinds of insects, but with different sizes of the same kind of insect.
Harrison and graduate student Scott Kirkton tested the aerobic performance of grasshoppers given varying amounts of oxygen, and found that smaller grasshoppers can hop nonstop in atmospheric oxygen levels lower then that of our own (21%). In fact, the smallest grasshoppers didn't even have problems in oxygen as low as 5%.
As for the larger grasshoppers? They were quite the contrast from their smaller brothers and sisters, as they tired out faster and their hopping rates rapidly dropped to zero. When extra doses of oxygen were given, however, they began jumping more, strongly suggesting an oxygen-stimulated boost which increased their performance.
The same was seen with dragonflies. As has been shared, fossil dragonflies the size of hawks have been discovered. A dragonfly of such size calls for a dragonfly with a long trachea, and in experiments where oxygen levels were greatly reduced, the dragonflies, not even half as large as their fossil ancestors, went from effortless flight to desperate exertion. The specimens couldn't even get off the ground at the lowest oxygen levels!
This is because the flight muscle of an insect burns more oxygen than any other animal tissue, and scientists know this well. It is a powerful, beautifully designed machine, depending on oxygen to run akin to a car depending on gas. The fact is this: the amount of oxygen supplied to an insect’s muscles, such as those of a dragonfly, directly depends on the amount of oxygen in the air. Therefore, the results of Harrison's experiments make perfect sense, and shed light on the type of atmosphere insects of such large size, such as dragonflies, grasshoppers, etc., would need in order to survive.
Arguments & Objections
As stated before, many evolutionists believe the earth had higher oxygen levels in the past (millions of years ago), as do many creationists (before the flood, thousands of years ago). Some creationists, however, are reluctant to believe such, citing that the Bible isn't clear on the subject and that other factors could contribute to gigantism in the insect world. True, but the Bible isn't clear on a number of scientific subjects, so it is an empty argument. Also, such creationists who cite the contrary do not provide plausible explanations.
Some espouse that gigantism was a result of purer genes, which consequently mutated after the flood (as a result of bottleneck). This argument, however, holds little weight, as flood-believers know full well that insects were not taken on the ark, and therefore would not have had a bottleneck problem (where a small number of individuals were left to breed. Insects can survive flood scenarios better than animals can).
The second argument is that some insects can increase oxygen delivery by a mechanical pumping action of their bodies, and therefore aren't as dependant on oxygen levels. While this is true of some insects, it doesn't explain all of them. Furthermore, and more importantly, Harrison's experiments strongly refute such an argument. The larger grasshoppers and dragonflies were not able to cope with lower oxygen levels, while the smaller specimens were able to. It is clear, then, that the larger grasshoppers and dragonflies were not able to utilize any type of pumping action to accommodate their altered environment.
The third and final objection is that not all fossil insects are of large proportions. Notice that this argument fails to deal with the ones that are large. Consequently, it is irrelevant.
In short, both evolutionists and creationists who take umbrage against the theory need to provide convincing counter-arguments. The evidence can't be ignored.
Greater Air Pressure: Evidence & Reasons
Quetzalcoatlus & The Problem Of Overheating
Even if we could bring dinosaurs back to life, it wouldn't be enough, says Octave Levenspiel, an emeritus professor of chemical engineering at Abiqua State University. According to him, one thing stands in the way, and that's the earth's present atmosphere, which may be only one-eighth as dense as it was many years ago.
"Today's South American condors - with their 12-foot wingspans and 25-pound weight - are the largest creatures that can support and propel themselves through the air according to basic aerodynamic principles," said Levenspiel. "The pterosaur quetzalcoatlus had a wingspan of more than 45 feet - half that of a Boeing 737 - and weighed more than 150 pounds. Either it couldn't fly - but it did or the atmosphere had to be much denser at the time."
Levenspiel postulates the earth's atmosphere was at least eight times denser "100 million years ago." Much less power is needed to fly at greater atmospheric pressures, so such conditions would have given the largest pterosaurs a much easier time flying.
Not only that, but according to Levenspiel, the giant land-dwelling dinosaurs would overheat today for the same reason. "When creatures become very large, they have more trouble removing heat," he said. "A denser atmosphere removes heat faster. An atmosphere eight times denser would have allowed the giant dinosaurs to survive."
In other words, sticking a large dinosaur in a modern-day theme park wouldn't just be a walk in the park. Your dinosaurs would, sadly again, go extinct.
Arguments & Objections
Some simply think the Quetzalcoatlus could fly in an atmosphere like ours today. Like a hand glider, it would have just needed to pick a suitable spot with enough distance to run and height enough to jump from. Obviously, such a situation would be awkward, and just plain silly. As for large dinosaurs and overheating, it is possible that they possessed some type of internal mechanism for keeping them cool, but evidence of such has not been found.
Greater Air Pressure: Evidence & Reasons
Ancient Amber & Ancient Air
As displayed above, many articles have appeared in recent years discussing the topic of ancient amber and oxygen levels. In short, the evidence seems clear. Earth's atmosphere once contained more oxygen, specifically around 35% (as opposed to today's 21%). Tiny bubbles of ancient air trapped by successive flows of tree resin have been discovered in ancient amber, and analyses of the gases in these bubbles reveal these startling numbers. Lest the skeptic argue insufficient testing, the results were based on more than 300 analyses by USGS scientists. Interestingly, the amber samples were also from different evolutionary periods ... the Cretaceous, Tertiary, etc., and even came from 16 world sites. The oldest sample tested was said to be about 130 million years old.
Arguments & Objections
The only argument given (and a very poor one) is the idea that some amber bubbles don't contain such high levels of oxygen. Notice that this argument is identical to the one in reference to large insects ... that is, "that not all fossil insects are of large proportions." As stated earlier, so we'll state again. This argument fails to deal with the samples that do contain higher oxygen levels. Furthermore, it is easier to make sense of amber bubbles that contain lower oxygen levels, as leakage could have taken place. However, endeavoring to make sense of amber bubbles that contain more oxygen is indeed rather a more difficult task.
To Be Continued...