Weekend Link Love – Edition 208

Research of the Week

A recent vision study finds that men are better at detecting rapidly moving images and perceiving fine detail, while women are better at discriminating between colors. The study’s author was unable to establish a clear evolutionary reason for this development, but I’d love to hear your guesses.

According to a new independent report by Consumer Reports, rice and rice-containing products are showing up with high levels of inorganic arsenic, with brown rice tending to have higher levels than white rice (due to its accumulation in the hull).

Researchers have documented the step-by-step process by which an organism evolves a new function. Big whoop. Now do macroevolution.

(Kidding with those last two sentences, of course.)

Interesting Blog Posts

Matt Metzgar discusses what he sees as the central problem in running: overstriding.

“Do the elderly need Paleo more urgently than the young?” wonders Paul Jaminet.

Media, Schmedia

After years of promoting a high-carb, low-fat diet, renowned South African professor of sports science and exercise Tim Noakes now supports a high-fat, low-carb diet – even for endurance athletes.

Disgraced heretic Tim Noakes has earned a sharp rebuke from concerned doctors in South Africa, who warn that his new dietary recommendation goes “too far” and threatens the lives of everyone whose ears it graces.

Everything Else

Prehistoric cave artists were rudimentary animators, using flickering torch light to create “moving” images of wildlife. Awesome.

Gluten comics.

This video of a pig saving a drowning goat may not have much to do with Primal living, but c’mon – it’s a pig saving a drowning goat.

Finally, someone’s come up with a good use for corn.

Recipe Corner

  • Delicata squash – the underrated winter squash, in my opinion – with apples and chili spices.
  • Every once in awhile (or more than that if you prefer), it’s nice to swap out the grass-fed beef ribeye for a grass-fed lamb steak.

Time Capsule

One year ago (September 24 – September 30)

Comment of the Week

Getting a dog for exercise is an excellent idea. First you have silently stalk through someone’s yard,lunge for the dog, and make off with it before they can catch you. Depending on the weight and thrashing of the dog it could be quite a challenge. That’s a full-spectrum workout.

-Not quite what I had in mind, but I’ll admit that Animanarchy’s suggestion would technically provide a great workout.

About the Author

Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.

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72 thoughts on “Weekend Link Love – Edition 208”

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  1. You would be surprised how many people ask me if that cat litter is made up of GMO corn.

    1. I was going to say that ANY reason to grow more GMO corn is a bad reason, be it ethanol, cat litter or a new miracle cure for the common cold.

  2. Cool video of the pig.

    Mark – Can you do a post on how the use of earphones affect us? I tend to use my ipod quite a bit..

    1. I destroyed my hearing by taking a very loud radio signal while wearing earphones. I’m left with a 50% hearing and word recognition loss. It’s a long story and I admit I shot myself in the foot.

    2. I am convinced I will invest in hearing aids in the future, because of the use of headphones and super loud music directly into their ear drum.

  3. “A recent vision study finds that men are better at detecting rapidly moving images and perceiving fine detail, while women are better at discriminating between colors. The study’s author was unable to establish a clear evolutionary reason for this development, but I’d love to hear your guesses.”

    That it was to do with food acquisition, that being one of our most important activities, would be one guess.

    Perhaps men would need to be good at following movement in order to hit moving game with missile weapons.

    Conversely, women would require to be particularly good at spotting particular edible plants to gather. A few leaves might indicate a tuber underground for example. The ability to finely discriminate between colors might be helpful in spotting the leaves you’re looking for.

    All of that’s completely speculative and totally unprovable, of course.

    1. No offence, but this is a very short sighted interpretation of hunter gatherer subsistence strategies and while it is the classic view it also seems to be wrong. Admittedly, all of the big game hunting in existing and historic H/G groups was/is performed by men, yet not all of the meat eaten by these people come from big game.
      Arctic and Subarctic peoples are a very good example of just how wrong this line of thought can be. The men hunted the big meat, reindeer, seal, walrus and various whales, yet these meats did not make up the majority of their diets. Women’s meat, rabbits, ptarmigan, geese, etc made up the majority of these peoples protein intake, and while some of these animals are taken with snares Aleut and Inuit women (and many other groups) took these animals with bolas and slings, both of which require far more skill and hand eye coordination than bows or atlatls do. To add insult to injury for years most anthropologists labeled women’s hunting as gathering simply because they weren’t taking big important animals.
      If we look beyond the historical record at the Clovis people, the supposed first Americans who were the quintessential mammoth hunters, we see the same thing. The Gault site in Texas is a very good example. Gault was a Clovis settlement site which was used for around 1,000 years, it’s a site where one would expect to find massive numbers of mammoth, mastodon and prehistoric bison remains. While remains from all of these animals are found they are not found in the numbers to be expected, but what is found are hundreds of thousands of turtle remains and bones of small game animals, woman’s meat.
      I feel there is likely something deeper going on here than a simple hunt/gather dichotomy.


      1. Have you ever hunted rabbit? When they see you, they freeze. It’s the slight variation in color compared to the background shadows and shape that gets them noticed. When they’re running it’s too late to catch them – they’re too fast

        Ever find a turtle in the forest? They’re not known for their speed, but for their shell – that happens to almost match their environment perfectly with shape, shading, and color. It takes a keen eye to see one unless it happens to be in the middle of a road or rock or is moving.

        Look at pictures of ptarmigan and other small birds and guess what? They also blend in almost perfectly and take a pretty keen eye to find.

        FYI, My wife and I bowhunt rabbit, deer, squirrel, and small birds together and my wife almost always sees the small animals and birds before I do. I almost always see the deer first.

        1. one more thing, any idiot can see an elephant (mammoth) but imagine what kind of hunter can spot the non-moving bird in the link at 15 yards (the effective hunting range with primitive weapons). Again, it’s slight variation in color, not movement that will let you kill/eat this bird


        2. If the superior color vision of females is the key to spotting camouflaged small game, how do you explain that colorblind people were found to be better at spotting camouflaged game, and the fact that colorblindness is more common among males than females?

          Dichromats Detect Colour-Camouflaged Objects that are not Detected by Trichromats, https://www.ncbi.nlm.nih.gov/pubmed/1354367
          “We conclude that colour can interfere with segregation based upon texture, and that dichromats are less susceptible to such interference.”

          Color Blindness: More Prevalent Among Males, https://www.hhmi.org/senses/b130.html

        3. And wouldn’t the superior avg red-green color vision of females be more useful for spotting red fruits among green foliage than spotting a black and white rock ptarmigan?

      2. Nice post a lot of good detail there, but do you have evidence that the “women meat” was only caught by the woman? what evidence is there that the men didn’t actually catch the majority of “women meat”. It wouldn’t make sense for the women to catch the majority of the meat due to other feminine issues they would have to have tended to. The “Women meat” may have been the majority of what was eaten, but that doesn’t mean the over-all majority of the meat wasn’t caught by men.

        You’re also not taking into account studies that prove women have a better ability to remember the places of certain supermarket items, which the studies seem to conclude in that women adapted the evolutionary ability to have a greater memory for the places of certain foods (you know the way mom always knows were you put something you lost in the house?)

        1. If the hunter dudes were out on a prolonged hunt, even more than a day, the ladies still had to feed the kids. Not unlikely that the pre-historic Suzy Homemaker would watch the kiddos and arrange the grasses in a rock vase while Tomboy Jo went out and rustled up some rabbits, fish and turtles until the dudes came home with the big money kill.

      3. This is interesting!

        I know that colour blindness is an X linked condition, which makes me wonder if other genes for colour reception are also located on the X chromosome, and thus women with their two X chromosomes would be more likely to get a full complement of colour detecting genes.

        I have no idea how to explain men’s ability to detect rapidly moving images though. Of course the study doesn’t tell us how profound the differences are. I’d like to see it graphically illustrated, to see how much overlap there is between men and women, and thus how great the differences are.

    2. I recently finished an M.S. in experimental psychology. One of the areas i focused on was evolutionary psychology. I reported on an article, which I am now unable to find, that argued what some are saying here; that is, that men evolved to perceive movement better and women evolved to discriminate between colors. The catalyst was simple division of labor through hunting/gathering. Women’s color discrimination was very important because telling the difference between good and bad berries/plants/etc. may mean the difference between life and death.

      1. This kind of thing annoys me. As a fine art painter I have very good color discrimination skills. I am also a man. My wife’s ability to distinguish colors is very poor in comparison (though she always thinks she’s got a match, she rarely does) Why is it so easy to go from ‘the average mean score in a group of tested men was lower in color discrimination’ to ‘men are lower in color discrimination’. Those two sentences are not the same. Choices are not binary. Outliers and variation are (usually) more the rule than the rule itself. Anyway, pet peeve of mine.


        1. I haven’t noticed anyone saying that all men don’t have good color discrimination, only that ON AVERAGE, females tend to have better abilities. I was in a college class where the professor mentioned some obscure color I had never heard of and asked who knew what it was. The class was about 50/50 male/female. More than half the females raised their hands, and only a couple males did, out of about 30 or so.

    3. That was precisely the first thought that I had! Also maybe because sometimes subtle changes in skin color can be the first indication that a kid is getting sick?

  4. The best use for corn, aside from eating fresh, organic, local corn on the cob, is making organic corn tortillas, which I enjoy several times a week.

    (I’m in the forums as Hedonist2)

  5. the animated cave drawing discovery is awesome – really! i had always wondered semi-conscious why all those images were laid out with multiple drawings of what seemed to be the same animal –

    but this is absurd – our lives were short, brutish and nasty – this is some liberal conspiracy! ( ;-0 )

    Don’t go back to sleep…

    1. but that woman standing there blinking and swaying from side to side waiting for me to click her (natural cat litter)

      …IS CREEPY!

      1. She’s doing the slow eye batting that cats do to make you think they’re friendly. I think she has toxo.

        1. Probably stands uncomfortably close during conversation and kind of leans over you too.
          Sign of a crazy cat lady.

  6. Men hunt, and so need the acuity to follow their swift-moving prey while women gather, needing to distinguish edible things as they slowly forage.

    My 2 cents.

    1. Exactly, pretty much, what my comment was going to be. Further, men on the hunt have to watch out for animals that might be hunting them.

      1. Right on! Men probably range further when hunting and explore new territory first. That new territory may be part of a sabretooth’s range. Also, I’m sure more deer got eaten than mammoths, so throwing a spear and hitting a fleeing antelope would be a man’s job.

        1. Deer are surprisingly easy to get close to. Many times lately I’ve been walking around, not trying to be sneaky (though I’m habitually light-footed in nature because it feels better so I don’t make a ton of noise) and seen deer oblivious to me. It’s satisfying to stand there and wait until they notice or creep a bit closer to them.

    2. Precisely, you hit it right on the mark. Men, being the main hunters of most indigenous tribes, had to be able to spot and track an animal for a long time. While women, mainly gatherers, had to determine whether a fruit or vegetable was ripe, poisonous or unpoisonous. I love how evolution and adaption works.

  7. It’s obvious women are better at discriminating between colors to critique the clothes of her friends

  8. The pig/goat video is cute, but it seems staged to me; I think that guy throws the goat in the water and then trains the pig to go after it.

  9. Not only are “women are better at discriminating between colors;” men have higher rates of color blindness–especially red-green colorblindness. It used to be thought of as a defect, until scientists discovered that colorblindness enables better spotting of animals in camouflage, moving animals, and at night.

    This fits with the evidence in hunter-gatherer societies of males being more geared toward hunting and females toward gathering, and of humans and pre-humans having a varied, adaptable, omnivorous dietary past with insects, wild game and fruits/berries playing a role.


    Dichromats Detect Colour-Camouflaged Objects that are not Detected by Trichromats, https://rspb.royalsocietypublishing.org/content/248/1323/291.long




    Molecular evolution of trichromacy in primates – https://www.ncbi.nlm.nih.gov/pubmed/9893841).

    https://www.archimedes-lab.org/colorblindnesstest.html (“Color vision deficient people have a tendency to better night vision”)

    The Upside of Color Blindness: Color-blind monkeys make better insect hunters. So what if you can’t be a pilot? https://discovermagazine.com/2007/apr/the-upside-of-color-blindness

    The Primates: Primate Color Vision, anthro.palomar.edu/primate/color.htm

    Evolutionary changes in Primate sensory capacities (requires purchase), https://www.sciencedirect.com/science/article/pii/0047248474900037

    Fossils of “Most Primitive Primate” [closely related to flying lemurs and tree shrews] Found Near Yellowstone, https://news.nationalgeographic.com/news/2007/02/070201-primates.html

    Flying Lemurs Are Primates’ Closest Kin, https://news.nationalgeographic.com/news/2007/11/071101-lemur-relative.html

    1. My brother-in-law says the best thing about being colorblind is that his wife NEVER asks him to sweep, mop, vacuum or wipe anything down.

  10. I think the color thing is more about protecting and nuturing. Spotting prediators and poisonous plants before your little one can get eaten or put something deadly into their mouth, or get bitten by a deadly spider or snake.

  11. A lot of people have been lambasting Prof Noakes in the media but he is doing well in rebuking them 😉 I was at his seminar when he was presented a lifetime award for his contribution to sports science. He was the one that initially convinced me to try Paleo, and I haven’t looked back since (including a drop in my overall cholesterol and blood sugar)! His book is very interesting and he is driving a new way of thinking in South Africa. I just wish the rest of us weren’t so short sighted.

  12. We have the joke in our house that men cannot find anything unless it is moving. Where is the butter? Seems like crazy question to us women.

  13. The article about the elderly and primal eating is really interesting and should be interesting to all ages. Don’t miss it because you think it doesn’t apply to you.

  14. Actually the cat litter made with corn isn’t even a good use of corn. It’s the worst cat litter I’ve ever used. Even my son, who never notices anything, complained at how bad the stink was.

    1. Corn makes awesome rabbit litter though. According to what I’ve read, they are much more susceptible to lung problems due to silica. Until we get the new cages finished, I have two rabbits with solid bottomed cages, so a litter box in each cage is a must. They’re outside, so smell is less of a problem.

  15. >> Matt Metzgar discusses what he sees as the central problem in running: overstriding.

    Nothing new. The idea od bare/minimalist running was born exactly of this problem, which results in feel striking and a greater injury risk and rate.

    I am not sure I like when the Paleo experts, whom I admire and listen to when it comes to nutrition, talk about running. For some reason they always get it wrong.

  16. Men/ evolution eyesight standpoint:

    Women are better at color perception (cone evolution)

    Men are better at visual acuity (cone cells as well)

    It’s good to note that cone cells function best during well-lit situations, and rods, the other of the two cells in the eye responsible for perception, is at it’s peak during the night, with low light.

    During the day is when visual evolution was most important (right?)

    women need color best because… Well I don’t have an answer. I thought because it would be most helpful for those women to detect fruits, but there is no way evolution would ‘know’ women were only responsible for that, and even if only women picked the fruits, men would eat them too. there would be equal evolution, you know?

    men: acuity because they were on their toes, independent, and quick to judge. while the women bore the children and nurtured.

    as a woman, i’d like to know about this colorful evolution, it’s interesting!

    1. If the women pick poisonous fruits, eat them, and give them to their husbands and kids as well (sounds like Genesis, right there), they’ll be stopping themselves from reproducing well enough. Whereas a colorblind man, if he sticks to hunting, won’t be a liability for the family or tribe.

  17. Re: the link on grass-fed lamb steak – seriously, if there’s a Whole Foods near you and they still have Icelandic lamb available, get some. It’s pricey as hell, but it’s the most delicious meat I’ve ever tasted in my life.

    The first time I got lamb in a restaurant in Iceland, I thought, “WOW this is a great restaurant!” But around the the third time or fourth time, I realized, “WOW this is a great animal!”

    The sheep in Iceland are descendants of the original flocks the Vikings brought there 1000 years ago. They’re still raised the same way they’ve always been, in one of the most un-polluted natural environments on the planet – this is probably *exactly* what meat tasted like a thousand years ago. The Vikings weren’t Paleolithic, but it’s close enough for me 🙂

    I swear I’m not shilling for Whole Foods – Whole Foods annoys me in many ways, but it seems like the two places to get Icelandic lamb are Whole Foods and Iceland, and Whole Foods is still – even with their markup – cheaper.

    Yes, the tiny chops (they slaughter them young) at $19.99 / lb are exorbitantly expensive – but pan-sear them (briefly!) in some olive oil with a little garlic, rosemary, salt & pepper, and you’ll marvel at what a great deal you got.

    (I also heartily recommend Iceland, but that’s less on-topic :-))

  18. What would be interesting is to know whether these vision findings are seen across cultures. Isn’t it possible that if you are examining only American college students (and staff) that you could be seeing cultural effects – i.e. boys play more video games, girls read more fashion magazines? I’m not saying the findings wouldn’t hold up in other cultures, but it seems to be jumping the gun a little to say: “we found these differences in vision among some American college students, therefore (all) men see differently than (all) women, and it must serve an evolutionary purpose.”

  19. my theory is pretty much similar to what some people on this post have mentioned. Because men went hunting and their prey seldom sat still, they would have to hunt fast moving prey and be able to quickly perceive any minor changes in the background to spot movement of a prey. But I think it is also to do with how men’s minds’ are programmed: men are known to think through their heads while women think through their hearts. Its also a big fact that women are more inclined towards fashion and grooming and hygiene than men. Women tend to take better care of themselves than men. I think it is got more to with the “wiring and chemistry” of our bodies than just pure conditioning. Because the female of most species display similar traits (grooming, a less physical and aggressive nature outwardly and a more emotional and social nature), I think it is to do with internal body and mind wiring.

  20. In general I’d agree with MOST of what I’ve read here, but I’ve seen so many individuals as evidence to the contrary. I bet these older societies had men who gathered and hunted small game with women, and I bet there were a few women who kept up with the male hunters.

    I don’t think one is more important than the other.

  21. Thanks for the link to Paul Jaminet’s Perfect Health Diet site, Mark. Forgot how awesome a resource it really is 🙂

  22. Interesting thoughts by the doctors against Tom Noakes.

    “This is dangerous because we don’t know if it works for everyone.”

    Well, duh. You know that the current paradigm doesn’t work for everyone, and logic would suggest that if you know one thing (Heart Healthy) doesn’t work for everyone, and you don’t know if another thing (arterycloggingsaturatedfats) will work for everyone, then you might try the unknown treatment on the known failed cases of the first treatment.

    It’s amazing to me that as often as we do this with powerful, expensive, laboratory-synthesized drugs, we won’t do it with something as simple and ubiquitous as the food we eat daily.

  23. Whenever I read objections to the paleo diet from CW advocates, there arguments are generally that it’s expensive and it can’t be sustained in the long term. Both are weak arguments. And here the argument against Tim Noakes’ stance is that “we don’t know if it works”. It makes me want to scream,well, go do some research and then form an opinion! There are thousands of people who are finding success with this manner of diet.

  24. “A recent vision study finds that men are better at detecting rapidly moving images and perceiving fine detail, while women are better at discriminating between colors. The study’s author was unable to establish a clear evolutionary reason for this development, but I’d love to hear your guesses.”

    It’s the testosterone…

    I cant remember where I found the article, but it was very eye opening.

    Basically it reports anecdotal evidence from several women who had sex change procedures, which included hormones = testosterone.

    They noticed significant changes in how they perceived things. It was easier to visualize their surroudnings. Focus improved. Details, drive, etc.

    Whereas previously, before the treatment, they had less immediate focus on tasks at hand, and had a more pronounced “overall picture”, with less focus on details, and more focus on the final destination, so to speak.

    I guess that’s why women naturally suck balls at driving…

    1. Dan, you can naturally suck MY balls for saying something that stupid. Every person I know who lost their license due to reckless driving and stupid mistakes happened to be men, compared to only one woman.

      Just another sexist Paleo. The web is full of them.

      1. “reckless driving” is an opinion (unless there was a crash involved). If you are driving (riding)to pick up the berries, you drive one way. If you are dodging the mammoth you just speared…it’s not so reckless to put the foot down. ,ales sense to me 😛

  25. American Indians used “Splatter Vision”. Put your two arms straight out to your sides, shoulder height, and wiggle your fingers. If you can see your fingers wiggle, you know you are using splatter vision. Now go outside and practice this method and you will see any little movement in your now much larger field of vision. Birds pop up everywhere when you didn’t see any before. Modern man is so out of touch and balance now and we really only use tunnel vision. We can get by on this now, but in the pat, it woulda killed us!

  26. I won’t speculate on why men see movement and women see color, but I can tell you that modern men and women tend to have such weak powers of observation of any kind in the natural world that I’m constantly astonished by it. Most cannot seem to learn how to find their way on a frequently hiked trail, remember how to drive to a trailhead they’ve been driven to more than once, identify poison oak, flowers or other plants, identify any kind of animal, insect, lizard or snake even when repeatedly instructed, know which direction they are facing even when you can plainly see large objects like the Pacific Ocean, figure out where to find shade on a hot day, identify known peaks when seen from another angle, etc. I can go on forever with how little most modern people are capable of seeing.

  27. Diane,

    If modern people were transported back a few thousand years they would have to learn how to find their way around and identify dangerous plants and animals etc – either that or die.

    If stone age people were transported forward to the present, would they know how to drive a car, use a computer or obtain food from a vending machine?

    Essentially our bodies are still adapted for the “stone age”. Thats why we are not adapted to eat modern processed foods and we are susceptible to many diseases such as cancer, heart disease and diabetes.

  28. No wonder it was the pig who saved the goat. The people just stood around filming it struggle.

  29. Good Use for Corn(besides whisky)? – Fish Bait
    Difference in Male/Female? Could be protective…Women guarding themselves and children need to detect an predator stalking them… Men as a hunting party are already armed and need to react… But it could be as simple as women needing to detect nuances of a mates temperment and/or the group…color being only one aspect… But basically they are saying that women have more cones in the the retinas (means color) and men have more rods…(means better peripheal and night vision)

  30. Hmm is anyone else experiencing problems with the images
    on this blog loading? I’m trying to determine if its a problem on my end or if it’s the blog.

    Any feedback would be greatly appreciated.