Friday, February 03, 2012

How to feed a pregnant Neanderthal

Shorter can be better: Case in point, Bryan Hockett has a short (five pages) paper in press in Quaternary International entitled "The consequences of Middle Paleolithic diets on pregnant Neanderthal women," and it is a ResearchBlogging.orgmust-read for anyone interested in prehistoric nutrition. In a nutshell, what he does here is consider what the hypothesized Neanderthals caloric requirements proposed by a number of recent studies (e.g., Froehle and Churchill 2009; Snodgrass and Leonard 2009) would have meant for a pregnant Neanderthal. In other words, are these estimates even realistic in concrete terms of the number and kinds of animals eaten?

The short answer is no. First, from a strictly caloric standpoint, the amount of food suggested by these estimates is huge, especially for a hunter-gatherer: "from the perspective of a modern fast food diet, a pregnant Neanderthal women would need to eat 10 large burgers per day (or three in the morning, three at mid-day, and four in the evening), or 17 orders of chicken nuggets per day (or five orders in the morning, six at mid-day, and another six in the evening" (Hockett 2012 2012: 2).

Second, and most importantly, the high amounts of meat suggested by the estimates would likely have been lethal for pregnant Neanderthal women. A nutritional ecology perspective emphasizes that humans need more than just calories to survive, especially on range of micronutrients (Hockett and Haws 2003, 2005). Here, using this approach, Hockett shows that the amount of meat currently generally assumed to have been eaten by Neanderthals would have yielded toxic amounts of protein (relative to fat), an unhealthy overconsumption of some mirconutrients (e.g., zinc, potassium - potentially damaging to internal organs), and a severe underconsumption of others (e.g., carbs, folate, calcium). In short, subsisting on a heavily meat-dominated diet given the energy requirements estimated in other published studies would have been impossible. This is all the more dramatic given that he emphasizes that terrestrial herbivores generally yield comparable ranges of essential nutrients. This means that no matter what land mammals they would have hunted, Neanderthals would still have not been able to get the micronutrients to stay alive, especially with the metabolic needs of a pregnant Neanderthal.

This ties in with recent literature that I have discussed on this blog that shows that Neanderthals routinely consumed other kinds of foods than terrestrial mammals, including plants, shellfish and sea mammals, all of which are rich in various essential nutrients often not found in terrestrial mammals. This paper goes a long way to show that hypothetical reconstructions of past diets need to be confronted both with their overall nutritional implications and with archaeological data, the latter of which clearly shows that Neanderthals readily exploited other resources where they were available. As Hockett emphasizes in his conclusion, this is not to say that Neanderthals and modern humans necessarily had comparably broad diets, or that the Neanderthal diet must have necessarily been 'modern' (think about it: is there anything inherently modern about a grizzly bear's diet, even though it sustains it and draws on many resources?). However, it does force people to start grappling with the question of how realistic some recent purported estimates of Neanderthal dietary needs and strategies actually are.

References  

Froehle, A., & Churchill, S., 2009. Energetic competition between Neandertals and anatomicallymodern humans.PaleoAnthropology 2009, 96-116.

Hockett, B. (2011). The consequences of Middle Paleolithic diets on pregnant Neanderthal women Quaternary International DOI: 10.1016/j.quaint.2011.07.002

Hockett, B., & Haws, J. (2003). Nutritional ecology and diachronic trends in Paleolithic diet and health Evolutionary Anthropology: Issues, News, and Reviews, 12 (5), 211-216 DOI: 10.1002/evan.10116


Hockett, B., & Haws, J. (2005). Nutritional ecology and the human demography of Neandertal extinction Quaternary International, 137 (1), 21-34 DOI: 10.1016/j.quaint.2004.11.017


Snodgrass, J., & Leonard, W., 2009. Neandertal energetics revisited: insights into populationdynamics and life history evolution. PaleoAnthropology 2009, 220-237.


10 comments:

Maju said...

Eat your veggies, Neandermamma. ;)

Yeah, people who think that in the Paleolithic (Neanderthals or Sapiens) lived only on meat must certainly be wrong.

Still I wonder how much are they driven to believe such things based on the typical prairie Native Americans' diet, which, for what I have read was actually very much meat-rich, mostly pemmican. Catlin at least does mention such a diet for his beloved Mandan, who were sedentary but only harvested green corn once per year and ate it then (no storing). On the other hand they lived by a river, so they surely ate fish anyhow.

Has there been any criticism of this kind of ultra-meaty diet among some hunter-gatherers? It's not just Neanderthals but there is in general that impression, probably false, that meat was ultra-central for hunter-gatherer's diet in all contexts, specially in the northern latitudes.

Camarchgrad said...

It's the Inuit syndrome.

There has been a conflation of the Paleolithic with the high arctic h/g lifestyle even though the south of France even during the LGM or any GM, would have been a radically different environment to modern arctic simply because of the amount of yearly sunlight.

It's probable that Neanderthals would have had access to an even richer variety of food, than today. Due to the collapsing of eologicl communities on top of each other.

Julian has anyone done some serious phytolith analysis with an eye to edible foods?

Maju said...

But Inuits traditionally ate mostly fish, seafood and sea mammals, all of which are out of the hyper-meaty diet claimed for Neanderthals (and sometimes also 'Cromagnons').

I think it has much more to do with the fact that archaeology generally stumbles on certain type of remains, for our case big mammal bones, and has a much harder time finding smaller-sized evidence like bird or fish bones or vegetal seeds/pollen.

Also gathering herbs or capturing rodents with traps is much less glamorous for most people's fantasies than bringing down a huge mammoth as we know Neanderthals did sometimes (or more commonly maybe bisons, deer, etc.) The very macho "big hunt" is much present when imagining Paleolithic way of life.

Put together the evidence factor with the glamor factor and that's it.

Julien Riel-Salvatore said...

Maju, CAG - I've been traveling and haven't had time to tackle the comments, but I'll do so soon... hopefully tonight!

JRS

Julien Riel-Salvatore said...

Maju -
good question about the pemmican. As I understand it, though, pemmican is extremely high in fat and often incorporated berries of various sorts in order to enable the eater to consume and digest the protein.

In general, there hasn't been a whole lot of criticism of high-meat H/G diets because they tend to be the exception rather than the norm. As you mention, in many cases (esp. northern ones), they were consumed a large share of fatty sea mammals that also yield other micronutrients. AFAI, there is nothing resembling the almost-meat-only diet that some of the isotopes folks have proposed for Neanderthals. I'm not saying they're wrong, obviously, since they're trying to make sense of real patterns in bone chemistry, but maybe we need a bit more comparative data from, say, high-latitude, ethnographically documented H/Gs before we take that hyper-carnivore interpretation to the bank.

Also, you make an excellent point about the 'romance' of large-game hunting... I think in part it has to do with the kinds of bones that preserve best in the record, but largely with the glamor dimension and how hunting large animals is perceived in much of W culture. This also has a lot of influence on how we think about early Paleoindian foragers in the Americas and their relationship to large animals.

JRS

Julien Riel-Salvatore said...

CAG -
also a very good point about the biodiversity of much of continental Europe as opposed to the Arctic. Hardy (2010) has documented that many edible plants would have been available to humans even at the height of the LGM, so there's no reason to disregard their potential contribution, especially given that N and C isotopes can only tell you about meat consumption, and very little about plant consumption (with some exceptions).

To my knowledge, the few systematic phytolith studies that do exist for Paleolithic sites tend to limit themselves to saying that specific types of plants were consumed by humans. I think it has to do with the inherent difficulty in extrapolating from observed phytolithis to the overall importance of certain plants in prehistoric diets... there's a jump there few people are willing to make at the risk of exposing themselves to (in my view rightful) criticism.

JRS

Camarchgrad said...

A note on pemmican. Most tribes mixed in Saskatoon berries, choke cherries or some other berry to give it a really healthful kick. Of course traditional pemmican has other less savory aspects such as human hair, or other contaminants.

Perhaps some bright young archaeologist will be able to get deer protein off middle palaeolithic berry phytoliths, and we'll have 70k pemmican.

Maju said...

Preserved berries can only retain that much of vitamins, notably vitamin C, which oxidizes very quickly. However it may have been enough to keep scurvy at bay, much as (unknowingly) a preserve of quince allowed Elkano to survive his famous first circumnavigation of Earth while most other mariners perished.

But what is being discussed here is well beyond the matter of scurvy: it is claimed that:

the amount of meat currently generally assumed to have been eaten by Neanderthals would have yielded toxic amounts of protein (relative to fat), an unhealthy overconsumption of some mirconutrients (e.g., zinc, potassium - potentially damaging to internal organs), and a severe underconsumption of others (e.g., carbs, folate, calcium).

Is that including inner organs' consumption (offals)?: brains and such are rich in fat and omega-3 acids, liver is rich in vitamin A and most of the B group (folate incl.) What about marrow? Blood? How strong is the nutritionists' consensus on these matters (they do not always agree)?

I do not have access to the paper so I am unsure on how these matters are dealt with.

I agree that calcium may be a problem and is a problem in almost any diet (even veggies, which are more balanced than meat, are relatively low in calcium relative to phosphate) in fact but calcium deficiency should not severely affect most people until their late 40s in most cases and by then most were dead anyhow. Also, potentially, eating mineral calcium (or from bone, eggs...) can be a preventive remedy.

While it's true that a hyper-meaty diet is unhealthy, it's probable that there were many options available even for nearly "pure" steppe hunters. And they would have used them for sure.

Julien Riel-Salvatore said...

CAG -
"Perhaps some bright young archaeologist will be able to get deer protein off middle palaeolithic berry phytoliths, and we'll have 70k pemmican."

That'd be pretty wild!

JRS

Julien Riel-Salvatore said...

Maju -
Hockett's estimates about nutrients do assume that internal organs of various sorts along with bone marrow would have been consumed daily, which makes his conclusions even more dramatic, IMO. PM me and I'd be glad to see what I can do about getting a copy of the paper in your (virtual) hands - might take a day or two since I'm traveling, though.

I also agree that prehistoric hunter-gatherers would have made ample use of any and all potential food resources in their environment.

JRS