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Messages - Warren Dew

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Research / Re: NOVA special - Becoming Human
« on: November 20, 2009, 10:09:43 AM »
I'm not sure how that relates to the pdf that Tarlach posted.  Are the hypotheses mutually exclusive or is there some way in which they can be reconciled?

Possibly humans are more efficient at walking than chimps, which is what your quote refers to, while humans are less efficient at running, which is what Tarlach's post addressed.

Research / Re: NOVA special - Becoming Human
« on: November 20, 2009, 07:39:17 AM »
Now the same person is just willingly accepting studies performed on mice.

Since this person was me, I'll explain the points you missed.

The point is that one should look at all the evidence, in context, rather than just picking out the parts you agree or disagree with.  Caloric restriction is about the amount of food consumed, and has been verified in studies from a huge range of animals, from paramecia to monkeys.  Since mice and humans both consume food, there's some basis for extrapolation.  Even then, I used the evidence only to confirm the existing data on long lived humans being smaller than average.

The mouse atherosclerosis data was claimed to be due to the types of food consumed, and not the total amount.  When you're dealing with types of food, though, you can only extrapolate to other creatures that eat similar types of food.  Mice and humans do not normally subsist on similar types of food, so the extrapolation is questionable.  It would be like claiming that cows will die on a diet of grass because humans can't survive on grass.  Again, all of the data is important, not just the sound bite.

I do see how people who are sloppy about data could miss those subtleties, but the fact remains that your examples merely illustrate proper analysis and how it takes into account all of the data, and not just sound bites.

Research / Re: NOVA special - Becoming Human
« on: November 20, 2009, 07:28:48 AM »
Something else, if this was not important, then why did we developed bipedalism.

Current evidence is that we developed bipedalism while we were still in trees.

With respect to the efficiency of bipedalism, which several other people mentioned, the human form of bipedalism is not especially efficient.  We're not really all that adapted to bipedal locomotion.  If you want to look for efficient bipedal runners, the best extant model is the ostritch, which has legs rather different from ours.

Research / Re: Coprolite -- a taboo source of information?
« on: November 19, 2009, 06:44:31 PM »
Notice that all of the species that this tribe ate are low in fatty meat, and more abundant in very lean meat.

Pronghorn are not especially low in fatty meat, though the other animals mentioned are.

Miscellaneous / Re: Ladies - are we all the same size???
« on: November 19, 2009, 04:52:00 PM »
My wife is 5'7" and 157 pounds, but she is 7 months pregnant.

Research / Re: Ancient Egyptians "were no hunter gatherers"
« on: November 19, 2009, 12:09:52 PM »
Here is the link to cordain's statement:

That's a good example.  I can't find any cite to the original article about the 800 year old eskimo in this web page.  In fact, I don't see any citations of peer reviewed articles at all on that page.  It all comes down to whether I trust Cordain's unsupported assertions, and after reading Taubes's book, I don't trust anyone's unsupported assertions.

If you think that exercise is so important for preventing this, then I'm really scared now! I'm still recovering from adrenal fatigue and have not been able to exercise in many years and I'm not all that close to being able to do that now either (at least not aerobic stuff, definitely not sprints/intervals, but weights I do and I'm no negatively affected by). Would the saturated fat plus no exercise equal bad?

I would guess that saturated fat makes little or no difference:  no fat plus no exercise would be bad, saturated fat plus no exercise would be bad, unsaturated fat plus no exercise would be bad.  Add in exercise and things get better, even if it's only some walking.  Again, though, this is just a guess.

Miscellaneous / Re: Sex life since paleo
« on: November 19, 2009, 07:04:08 AM »
Breastfeeding reduces your chances of getting pregnant.  A lot of women on the standard American diet can still get pregnant, though, probably because the extra body fat tells the body it has enough reserves to produce a second baby.  A paleolithic woman would not have had as much extra fat.

Research / Re: NOVA special - Becoming Human
« on: November 18, 2009, 11:32:42 PM »
We do know that exhaustive hunting was one of the most primitive methods of hunting that our ancestors employed.

We don't know that at all.  The direct evidence for persistence hunting comes from modern hunter gatherers, which are not even our ancestors in most cases.  Neanderthals engaged in ambush hunting with nonmissle weapons farther in the past than that, though they weren't our primary ancestors either.

We really have no clue what Homo erectus was doing 2 million years ago.  They could have been persistence hunting, but they could also have been ambush hunting or primarily fishing.  If they were optimized for sweat cooling - and that would probably involve hair optimized for evaporative cooling, rather than bare skin from which sweat wastefully drips off - they could have been using that advantage to scavenge by getting to corpses first, rather than to hunt.

Anything before Homo erectus didn't really have legs long enough for persistence hunting.

Research / Re: Ancient Egyptians "were no hunter gatherers"
« on: November 18, 2009, 11:20:39 PM »
I read that bit by cordain before and am a bit disturbed by it. Is anyone else worried about a diet that is probably giving us atheroclerosis?

I think "probably" is an exaggeration.  That's a very broad conclusion to draw from only one example.  For all we know, any atherosclerotic plaque in that one example was caused by lack of exercise rather than diet.

I also haven't seen a cite or an original article.  If Cordain misinterpreted the evidence, it wouldn't be the first time he'd done it.

One thing to keep in mind is that atherosclerosis has never been linked to deaths from heart attacks in women, and the few studies that have looked at it in men have had contradictory results.  It's also to be noted that different things can be interpreted as "atherosclerosis", ranging from fatty streaks that may be entirely harmless to fibroid plaques that are likely dangerous because pieces can break off and cause thrombosis or stroke.

Personally - and this is just a guess based on the limited evidence available - personally, I suspect that dietary composition may have little to do with risk of fatal heart attack.  I suspect that exercise has a lot more to do with it.  And I'll go even further against the accepted wisdom on this board, and say that for this particular issue, aerobic exercise is likely the best, as it likely promotes myoglobin in heart muscle that would allow the heart to survive a longer period without oxygen when thrombosis - a heart attack - does happen.

I'd love to see more actual facts and research on that, though.

Research / Re: NOVA special - Becoming Human
« on: November 18, 2009, 12:22:16 PM »
OK, I just watched it again, it's around time market 27:00 in Part 2. They studied the divergence of head lice vs. pubic lice, using the molecular clock, and inferred that we lost our body hair around 3 million years ago.
What they're saying there is not quite accurate, though.

In fact, head lice and pubic lice diverged much more than 3 million years ago (Mya); head lice are more closely related to chimpanzee lice than they are to public lice, and pubic lice are more closely related to gorilla lice than they are to chimpanzee lice.  The divergence that occurred 3 Mya was the divergence between pubic lice and gorilla lice.

That's been interpreted to mean that humans lost their body hair at least 3 Mya, enabling gorilla lice to jump to human pubic hair at that time.  I don't think that's the only possible interpretation, though.  These two different kinds of human lice could have inhabited different populations of hominids, making a jump onto a common host at some later time.

Miscellaneous / Re: Sex life since paleo
« on: November 17, 2009, 09:37:11 PM »
I started paleo around when my daughter was born; I suspect the latter has more to do with any changes in sex life.

Research / Re: NOVA special - Becoming Human
« on: November 17, 2009, 09:33:13 PM »
Sometimes you can see soft tissues in fossils, but it's much rarer.  It happens when an impression of the soft tissue (such as hair or leaves) on another substance such as mud becomes fossilized.

It can happen - like the feathers on that dinosaur found in China a couple years ago - but I don't believe that kind of impression has been found for paleolithic humans yet.  I don't think we actually know whether neanderthals were hairless - though some are recent enough that some soft tissue could be preserved - and I'm pretty sure we don't know about Homo erectus.

Personally, I suspect hairlessness and the invention of clothing happened together, and that they might explain the rapid spread of Homo erectus around the world.

Research / Re: NOVA special - Becoming Human
« on: November 17, 2009, 07:09:52 PM »
Yeah.  They don't actually know when and why we became hairless, since hair doesn't fossilize.

Diet and nutrition / Re: What's your take on raisins and prunes
« on: November 17, 2009, 11:55:40 AM »
I won't say that raisins or prunes are nonpaleo, but I prefer grapes and plums myself.

Introductions / Re: Not wanting to lose weight -- just to feel better
« on: November 17, 2009, 07:36:33 AM »

Usually people see a significant loss of water weight in the first week or two of paleo as the bloating comes down.  Don't worry, you won't disappear!

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