Ice Age Physiology

[JDL]

A while back I offered the opinion that bigfoot are the (surviving) megafauna member of the hominid family.

 

We've also discussed how hominid lung capacity increases with height and ribcage depth such that a human with a six inch longer torso has the advantage of better than a 50% increase in lung tidal volume.

 

I've also been noting with interest the increasing number of reported finds of submerged ice age settlements around the world.

 

Along with this, the recent discussion of large skeletons found in Midwestern mounds during the 1800's has set me to musing.

 

My intent here is to make as few assertions as possible.  What I want to do is throw out some raw thoughts and opinions and seek opinions from other members regarding their perceptions.

 

I've seen both bigfoot (in and near the Sierras) and large skeletons (of the Si-Teh-Cah on display in the Mark Twain Museum in the late 60's and 70's).  They did not appear to be the same species.  The Si-Teh-Cah skeletons, though tall, were not as robust or barrel-chested as the bigfoot I have observed.  I find it difficult to correlate them to the same species.  In addition, the Si-Teh-Cah skeletons were displayed with artifacts from the cave in which they were discovered (not the Lovelock Cave in this case, but from a cave near Walker Lake, about 100 miles South of Lovelock).  The artifacts included stone implements, atlatls, and rough textiles (similar in appearance to poor quality burlap).

 

So I do not believe that bigfoot and the race that produced the large skeletons found in Nevada or in the Midwestern mounds are the same species.  They seemed to me to be both physically and culturally different.

 

I do believe that the Si-Teh-Cah and the skeletons from the mounds are from the same race.  If not, then there would have to be two such races, and that is too much of a stretch for me.

 

So why would two species of hominid, both larger than modern humans evolve?  And why would one apparently survive to this day, while the other has apparently gone extinct?

 

So some speculation.  I think it is reasonable to say that both species existed and possibly arose during the last ice age.  What about the conditions then might have supported the larger size as an advantage, but also made it possible for large size to be achieved?  Then what difference between the two large hominid species that made the difference in their fates?

 

It must all come down to science in the end, so I got to looking at the environmental factors.

 

I think it's all about oxygen.

 

During the ice age, sea levels were estimated to be 400 feet lower.  At sea level, the air pressure is greater, which means that there are more oxygen atoms packed into every liter of air that you breathe.  Now take this four hundred feet lower than today's sea level.  The concentration of oxygen would be even denser (footnote: the graph showing the relationship between air pressure and altitude is not linear, it has a shallow slope at high elevations and a steep slope at low elevations, meaning that the lower you go, the faster air pressure increases).

 

Now on top of this, the air was cooler on the average back then.  Cooler air is also denser than warmer air.  This provides a second effect that would increase the density of air and increase the concentration of oxygen in the air.  We should also take into account that the air pressure vs. altitude graph we use today is based on temperatures common today.  I'm not sure how the graph would look exactly if calculated using lower temperatures, but cooler, denser air suggests that the slope would approach the vertical even faster than it does at today's temperatures.

 

There is a possible third effect, but I haven't had the chance to explore it yet.  Nitrogen is lighter than oxygen, weighing seven eighths as much as oxygen.  We all know that the ratio of oxygen to nitrogen in the air at sea level today is 21% oxygen and 78% nitrogen, but would it be the same at air pressures and densities caused by 400 foot lower elevations and ice age temperatures?  Probably not.  The lighter nitrogen would probably have a lower percentage than 78%, and the heavier oxygen would probably have a higher percentage than 21%.

 

So three different effects would lead toward more oxygen available in every breath, all day long for hominids living back then, throughout their entire lives.

 

So what effect would this have?  I recall having once heard, and haven't yet verified, that Jacques Cousteau once cut himself to the bone while living in an underwater habitat and that the wound healed in an astonishingly short amount of time because of the increased air pressure and oxygen concentration in the habitat.  So I decided to look into Hyperbaric medicine to see if this might be true.

 

I found that hyperbaric medicine (placing people in pressurized capsules with high oxygen concentrations) is now routinely used to treat burns and to treat necrotizing fasciitis (flesh eating bacteria), so whether or not the Cousteau story is true, there does appear to be some benefit associated with increased oxygen pressure and healing.

 

I also found that at Wake Forest University they are exploring the use of hyperbaric treatments to increase health and longevity.  They claim that increased oxygenation improves both the health and function of stem cells, allowing them to keep the body healthier and make it more resistant to disease.  They believe that by placing people in a hyperbaric chamber a few hours a week at pressures 66% higher than normal they might be able to live as long as 120 or 130 years.

 

Wow, right?  But think of this.  During the ice age people lived in what may have been fifteen to twenty percent higher oxygen concentrations their entire lives.  What does that mean?

 

Here come the maybe's.

 

Maybe the evolution of megafauna wasn't simply because bigger bodies (higher body volume to body surface ratio) made it easier to conserve heat.  This may have helped from a natural selection process, but perhaps healthier and better functioning stem cells made it biologically possible to grow larger.

 

Maybe, this mechanism led to the evolution of robust hominids the size of bigfoot.

 

Maybe this mechanism led to the evolution of a taller, less robust, race of people like the Si-Teh-Cah.

 

Maybe the larger lung capacity of the bigfoot was sufficient to sustain their modern size and mass (heck, for all we know they were once twelve feet tall, for all we know some still are based on reports, and some do believe that the average size of the local bigfoot is smaller the further South you go).

 

Maybe, the Si-Teh-Cah, even with larger lung capacity than a modern human, simply didn't have enough capacity to sustain the size and health of their larger, but less robust, bodies without the benefit of denser oxygen concentrations.

 

And maybe there's something to the lore about long-lived standard sized humans.  Living at ice age sea level, but in warmer regions, perhaps they did live for hundreds of years due to better oxygenation and healthier stem cell function.

[Guest Suesquach]

A lot to think about. Thanks JDL for bringing up this point of view!

[the parkie]

Some very interesting thoughts JDL, I need to do some reading...

[Guest Urkelbot]

Your still going on about the lung capacity. I would dig out the journal articles I posted about mammal lung function but you either failed to read them or ignored the data.

Lung size and function in mammals correlates to mass. This linear relationship is seen across the spectrum of all mammals.

I see no reason Bigfoot somehow bucks the trend and there has been no autoposy to determine Bigfoots lung size/capacity.

[NathanFooter]

JDL , interesting post, thanks for sharing.

[JDL]

Urkel,

 

Get off it.  Once again, human to human and hominid to hominid comparisons are more valid than hominid to mouse or hominid to mammoth, or mouse to mammoth, as you would have us do, particularly when there are plenty of specific articles on human lung capacity relative to size, which, I'm sure the vast majority of biologists would agree, is also more comparable to hominids in general than the average of all mammals is.  The graph you offered was just a scatter plot with a best fit line drawn through it.  Some species were right on the line and some were outliers.  It's easy science, but it is also freshman science.

[Guest Darrell]

^yes but JDL you are submitting a hypothosis containing total conjecture that presumes 1) that the skeletons allegedly found in the 1800 even existed and 2) that bigfoot lung capacity, an unknown as no specimen exists, would explain their alleged large size and superhuman abilities.  This despite published data counterdicting your hypothosis.

[Guest Urkelbot]

It doesn't matter if your comparing human to hominid or human to human or human to mouse. The ratio comes out almost the same. Sure there always outliers but there is no evidence that Bigfoots respiratory function falls 5 or 6 standard deviations from the norm.

It be one thing to claim 10% that might be believable but where in the world you pull 50% from I don't know. It feels like more Bigfoot fan fiction. The big magical Bigfoot with super powers. Why not argue that Bigfoot has decreased respiratory functions? Or is actually relatively weak, slow, or dimwitted. They can't maintain large enough populations to be detected by biologists after all. The fantasy is always more exciting I'm guessing.

Did you breakdown the pgf figure and approximate the lung volume, and all other internal tissue, and compare that against your guess of its mass? Where do your sources on Bigfoot anatomy come from?

[JDL]

Urkel,

If the ratio were the same no matter the species, the reference wouldn't present a scatter plot graph to begin with. The dots on the graph are the actual data. The best fit line is nothing more than a derivation from the data, and a poor one at that. No one can swing a derivation around clubbing people with it as if it were an immutable natural law. But let's say for the moment that it has as much value as one might want to invest in it. The reference would have no validity in predicting the same ratio in ice age mammals living in a more oxygen rich atmosphere. Change the conditions, in this case provide a richer supply of oxygen, and life will adapt to take advantage of the richer supply of oxygen. Clearly megafauna did exist, and I doubt they had the same physiology as today's mammals, or we'd be looking at more examples of them today.

Next consider each element that I have presented.

Does air pressure increase as you go down in altitude?

Does air become more dense as it grows cooler?

In a denser, cooler, higher pressure mix of oxygen and nitrogen would it not be that the lighter gas, nitrogen, would be more buoyant relative to oxygen than it is at standard temperature and pressure?

Was anything that I provided regarding current uses of hyperbaric medicine inaccurate?

There's nothing to argue against in any of these points.

I get it that some don't believe that either bigfoot or large skeletons exist. Fine by me.

I've simply offered some what if's for people to consider. I thought that they were well reasoned. I honestly didn't expect anyone to get enraged and mean-spirited about it.

Darrell,

You're right that I haven't seen any of the Mound Builder skeletons. I have, however, seen Si-Teh-Cah skeletons, so skeletons of similar description from a large race of people do exist, and I'm willing to believe that at least some of the Midwestern accounts are true. With regard to bigfoot, the specimens I've seen at close range were all barrel-chested. I've also heard them howl continuously longer than any human possibly could. I've also heard them screech, squeal, whoop, and scream with phenomenal volume. These all indicate significant lung capacity, and therefore better capacity for oxygenation. Where am I going wrong here other than to stipulate that bigfoot exist in the face of adamant skepticism?

Also please refer to my comments above regarding the validity of the "published data contradicting my hypothesis". A scatter plot of contemporary mammals with a derived best fit line is hardly predictive of ice age physiology in colder, higher pressure atmosphere significantly higher in oxygen.

Edited December 16, 2013 by JDL

[Guest Darrell]

So did you observe the Si Teh Cah skeletons and conduct specific measurements to document that these remains are in fact significantly larger than contempory or modern human skeletons? Because there are studies that have and dont find those specific remains out of the range for human skeletons.  

[hiflier]

Hello JDL,

I don't think many know how significant this discussion is. What you suggest with a hyper-onygenated environment has been studied in the area of paleontlogy with the results well known. About 1.8 billion years ago the great oxygenation period brought on by the bacterial colonies that were virtually in every nook and cranny on Earth caused plants, and later, insects to be of larger proportions than today. Dragonflies with four foot wingspans for example.

Then too hominid migrations followed the Milankovich cycles, which are the 100,000 year warm spikes that we see in the ice core records. The last Ice Maximum saw the low sea levels like you say. Some of the earlier Ice Maximums were severe enough to drop the sea 900 ft. Neanderthal saw not one but TWO of these Ice events. Plenty of land/ice bridges to go round during those periods.

Even in North America, the Clovis Culture apparently met their demise rather suddenly along with many megafauna by what scientists believe was a two-piece meteor bombardment in the Great Lake and Hudson Bay region. It's facinating stuff really. Sorry to ramble.

P.S. Nothing back rom the Smithsonian- YET.

Edited December 16, 2013 by hiflier

[JDL]

Darrell,

 

I'm pretty sure we covered that in the Giants of Lovelock Cave, NV thread back in August of 2011.

 

hiflier,

 

Thank you.  That's what I was looking for.  More leads.

[Guest LarryP]

 I've also heard them howl continuously longer than any human possibly could. 

 

 

 

As have I, JDL.

 

I've heard a tremenously long and loud whoop that was followed immediately by a thunderous deep howl that lasted around 20 seconds without a pause and grew in intensity the entire time.

 

That took tremendous lung capicity and will definitely get your attention, to say the least.

[Guest Urkelbot]

If you look at the statistics the allometric scaling on all respiratory functions is linearly related.  All the authors on this subject come to the same conclusion.  PULMONARY FUNCTION CORRELATES TO BODY MASS.  There isn't that much deviation and certainly not from two similar sized animals with similar lifestyles, humans and bigfoot. It doesn't matter that bigfoot may or may not have evolved due to ice age pressure so did all mammals in northern latitudes.  

 

But hey make up more nonsense you pulled out of thin air and claim it as fact.

 

 

http://www.uvm.edu/~pdodds/files/papers/others/1966/stahl1966a.pdf

http://www.tbiomed.com/content/2/1/31

http://www.researchgate.net/publication/15965986_Design_of_the_mammalian_respiratory_system._V._Scaling_morphometric_pulmonary_diffusing_capacity_to_body_mass_wild_and_domestic_mammals/file/79e415101929a70b39.pdf

[JDL]

Urkel,

 

Reading the references you've provided, none of them contradict my theory.  In fact, they each validate it in their own way. 

 

The Painter article points out that oxygen transport is a limiting factor in maximum metabolic rate, whereas I have postulated that if oxygen were supplied in greater abundance (were less limited), superior physiology can be achieved.  There's no conflict here.

 

And both Stahl and Gehr, et al. indicate that as mammalian mass increases, lung capacity increases, I've simply postulated that as superior oxygenation increases, then size increases.  This is a chicken and the egg argument.

 

From a comparative reference standpoint you and I only disagree in that I state that a direct hominid to hominid comparison is more accurate than a general mammalian trend to hominid comparison.

 

Seems a pretty picayune and distracting thing to argue about when your references and my references both indicate that superior respiration supports greater mass.

 

Got anything on ice age mammalian trends?  This would be particularly applicable.