Most People seem to agree that we cannot and do not want to go back to the past, but the reason given is often wrong; that time has moved on and what was can never be again. The truth is that we cannot go back to what we never left. Our home is the earth, our time the Pleistocene Ice Ages. The past is the formula for our being.
(Paul Shepard)

Tuesday, 13 December 2011

ashby and the atlatl

Hi, If you are a bow hunter or atlatl hunter (all two of you) you should be aware of the Natal study by Dr Ashby. The study was to look at the lethality of the bow before bowhunting was legalised in Natal.
Read the study it is really good and stands as pretty much a definitive work on lethality and projectiles As you know bows and darts don't kill larger game by hydrostatic shock so lethality is best determined by the amount of penetration an arrow can attain. Ashby was able to be very specific in his recommendations and nicely for us primitive types it looks like the ancient hunters pretty much had it sorted out way back then. The two downsides are arrow shaft diameter and shaft friction, both of which are harder to get "right" under primitive conditions. I have noticed that atlatl darts get less penetration than standard arrow shafts but they hit with a far greater "whallop"
In a past article I wrote about dart speeds and added the kinetic energy of the darts I will now
add in the momentum calculations.
I am not a mathematics whizz and have been told to work out momentum through mass x velocity I will use grams and MPH as measurements.

- pine dart: 105 gram - 51 mph or 74 fps
- Mark Bracken river cane dart: 118 gram - 56 mph or 82 fps
- Atlatl Bob aluminium dart: 67 gram - 61 mph or 89 fps
- Chris Oberg carbon dart: 91 gram - 64 mph or 93 fps
We found 65 mph for the fastest dart (river cane, 98 gram). Most of the dart speeds were between 55 mph and 60 mph.

My workings for foot pounds

pine dart 20.18 foot pounds

river cane 27.27 Foot pounds

aluminium 18.37 foot pounds

carbon 27.47 foot pounds

momentum

pine dart 5.355
river cane 6,668
aluminium 4,087
carbon, 5,824


for comparison .22lr 38 grain 1050 fps 69 ftlb (100yd) 2. 46 grams 715.9 mph (stats off the ammo box)

momentum
1761.114

so we can see how a .22lr varmint gun while whipping the atlatl in foot pounds compares poorly
in momentum.

A 150 fps stick bow shooting a 600 grain arrow gives us momentum of;
4.097 which (while an heavy arrow) does not compare that well with any save the aluminium dart.

thanks to ken for the formula

Thursday, 8 December 2011

scavenging revisited

this study
is about primate hunting and carnivory of particular relevance to the last post is the following;

However, evidence suggests that primates avoid scavenging even if the logistic support carrion is fresh [Ragir et al., 2000]


More here



Monday, 5 December 2011

Scavenger or hunter?

Scavenger or hunter?

We reinvent the past to determine the future and make sense of the present. The far past the paleolithic, with its lack of written evidence and (not so) scarce archaeological record is ripe for this kind of interpretive reinvention. In the 60s and 70s we viewed our very distant ancestors as “blood apes” a fierce little hunter who grew in stature and hunting prowess over the millennia and whose aggressive hunting tendencies explained the devastating 20th century wars. Biology resists the view of our distant ancestors being in any way vegetarian (though if it didn’t this is surely how they would be viewed) but the view of our time is of habilis as a scavenging tool user.

(side) I will assume for purposes of clarity that the current family tree is the correct one, but gentle reader, be assured that there is much controversy over who evolved from whom

How far back can hunting be attributed to the genus Homo? The general view at the moment is that early hominids obtained their meat by scavenging the remains of large predators before developing the tools to obtain carcases for themselves. In Europe at least Homo Hiedelbergensis can be attributed with accomplished big game hunting skills with tell tale weapon fractures on large game human butchering marks on bones of prime (and frequently only prime) animals and beautifully effective wooden spears. Bone evidence also exists for Africa and Asia.

However much of life for animals is ephemeral and is lost forever aside from the rarest of cases the evidence for a scavenging lifestyle is found on bones which have cut marks OVER the tooth marks of the four legged predators

Pat Shipman of Johns Hopkins University in Baltimore, one of the first to analyze remains at hominid sites with a scanning electron microscope. Her recent study of overlapping cut marks on 1.7-million-year-old animal bones suggests that the ancient prey were scavenged by hominids. Close inspection reveals that most of the cut marks created by hominid tools were made after overlapping sets of carnivore tooth marks were imprinted. Only 13 sets of overlapping marks have been studied however she adds,…….There are precious few rules by which organisms operate.

It should be noted here that stone tool marked bones recently found associated with australopithecus afarensis were on bones that bore no sign of non-human predation.

Many scientists and non scientists have shown that meat and marrow can be found scavenging on the African savannah, arguments for scavenging before effective tool use are mainly centered upon our slow paced bipedalism and relatively (compared to say, leopards) inoffensive bodies. Scavenging (scaring animals off game) is also practiced by some African traditional peoples today.

However there are no scavenging apes, not a one. There is a rule that palaeontologists’ use which is basically that fossil organisms must follow the rules of living organisms unless overwhelming evidence points to the contrary. For example; mammals have a heart and two lungs so extinct mammals must also have a one heart and two lungs. There are no scavenging apes or any solely scavenging, terrestrial animals (hyenas hunt more than lions).

There is no modern analogue of a scavenging ape (or monkey) indeed the two simians that live on the savannah (baboons and hadza) have a similar diet in terms of species of which the animal portion is mostly hunted. Our ape cousin the chimpanzee hunts exclusively, habilis was an ape armed with sticks and stones and smarter than either baboons or chimpanzees, it would seem odd if it were incapable of hunting at least small game. In fact I always found it less likely that it could scare off or defend any kill from any other scavenging animals. Even Hyenas run from Lions.

The cart does not go before the horse in that we did not evolve lungs and then decide to try them out on land. If you are a developed successful hunter it’s because your ancestor at least tried to be. Habilis may not have hunted game much bigger than a hare and may not have been that successful at it. Scaring lions off a kill maybe easy for a modern human as every animal on the planet KNOWS that humans are really bad news and stay out of our way. Lions couldn’t care less about jackals and are unlikely to have been intimidated off a kill by a 4’ scavenging Habilis.

Getting past lions, hyenas, Jackals or even vultures would not be easy for a “defenceless scavenger” so we might have to assume that Habilis would have to find kills or dead animals that had no predators on them and give up the bodies when larger animals arrived. Hadza women can scare leopards and lions off their kills by yelling and waving their digging sticks but we have to remember that Hadza do kill lions and leopards and, as humans, are a feared apex predator. Presence of scavengable game is not enough we need to see that it can be scavenged successfully. In addition can chance encounters with undefended kills have been enough to fuel the enormous increase in body size and brain capacity between species of homonid? Before you get onto bone marrow, animal scavengers eat bones.

I must admit that I have never really been convinced by the idea that early hominids obtained their meat by scavenging. Of course I am sure that some was and the evidence shows that at last some meat was scavenged but I suspect that a proportion was obtained through hunting. I am by the way in no way arguing that men provided the majority of calories while wife and baby stayed at home blah blah drone. What I am saying is that here we have a consensus that habilis was a scavenger based on fairly slight evidence and in opposition to a law of palaeontology (as I understand it). I would ask all use the word forager to describe habilis and indeed any “wild” hominid. Food gathered hunted or scavenged was located and foraged for in the environment where habilis lived.

why not iceland?


While I am in no way a fan of comparing the health of countries I am aware that it happens all the time. One thing I find interesting is the idea that Japan has the highest life expectancy and one of the lowest obesity rates in the developed world therefore they must be ultra healthy. They eat a high carb diet with low amounts of fat and animal products ipso facto so should we in the west. Comparing countries in this way really isn't helpful as there are so many mitigating factors and variables to make any comparison or statistic almost meaningless, and that's before we get into questioning how the statistics were collected, collated and reported. I am one BMI point away from obese (obese! I'm not even overweight) my slender wife is 'obese' and I know many other people who have been amused to find they are overweight/obese.
I lived in Japan for many years and I have since smiled slightly when I hear how healthy they are, as this is certainly not the impression one gets from living there. I won't bore you with the anecdotes or details. In addition life expectancy so often given as a marker of health of validity or life style choices is to my mind of no use unless it is coupled with good health until death. I personally know (and I'm sure you do too) people in their nineties with alzheimer's or severely restricted mobility or other serious health problems, you can keep that sort of longevity (Ancel keyes anyone)?
Regardless of that in the publics' mind and in the mind of the media longevity is the key marker for health, the main purpose for me writing this is that Japan DOES NOT have the highest life expectancy for males. The life expectancy a birth for males in Japan is 78 years while in Iceland it is 79.2 years. This compares with 76 years in the UK .
Japanese women live longest and this drags Japans' total for both genders to the number one spot. When I say this to people I usually get "oh but they have high levels breast cancer and CVD" which is of course quite true but when was the last time someone mentioned Japans' sky high stomach cancer or stroke death rates?
The main reason why I am writing about this is that Iceland eats diet high in saturated fats and animal proteins (dairy and meat) there is lots of rye and oats in there as well as plenty of sugar, it is by no means an ideal diet but it is the diet eaten by the world's longest lived male population.
This should of course be of interest to those of us with a northern European heritage (before my Grandfather died he revealed that our family had emigrated to Scotland from Iceland) and perhaps gives us a better model or basis for our lives and diets. I'm going to try to find more health data for Iceland to share I know that in the savage weather of the 16-18th centuries and after many in Iceland ate no grains but subsisted on dried fish.


Why don't we hear about this much??? If I said vegetarian conspiracy would you hold it against me?