Saturday, June 7, 2014

Reaching a Boiling Point

Hi all,

This test ended up deliciously.  I shot a rabbit the other night and thought I should explore an old cooking method called stone boiling.  I have taken part in covered hot rock cooking plenty of times in the South Pacific and have excavated the prehistoric remains of that cooking method on several occasions.  I had never tried cooking via stone boiling though.

Prepping to cook a size 2 pig at Aganoa, Tutuila Island, American Samoa. Bloody hands and fire is pretty fun combo. 2006.

Helping prepare a traditional Sunday lunch. Covering materials visible in background. 2010.
Tovio taking the hair off of a size 4 pig in the village of 'Aoa. 2009.
Wilson Fitiao taking a break from the fire in the village of Matu'u. Covering materials in background. 2010.

Hot rock cooking feature radiocarbon dated at 2400 cal. BP below volcanic ash at Vainu'u.  The stones were placed near a structural post for reuse later, look at the placement of posts in my other photos. I wonder whose initials those are on the tag board?

Cheap trowel that I snapped on 2700 year old cooking ash at Aganoa in 2006.

Really I just wanted an excuse to play with fire and eat wild forest critters at the same time.  The idea behind stone boiling is relatively simple, just plop a couple hot rocks into water and boil your meal.  Here's how this test went down:

First I needed a cooking vessel.  I could have just used a metal pot, but where's the adventure in that, right? Luckily we had a few dried gourds laying about so I set out to make a bowl and spoon with a few stone implements.  I cut the top off of the gourd, scraped the inside, plugged small holes with pine pitch glue and fashioned a spoon from the neck of the gourd.  All together the process took about an hour and a half.

Goose Neck gourd and basalt hot rock

Chert scraper used to remove seeds and tissue

Small holes patched with pine pitch glue

Cutting a spoon from the neck
I used chert for my scraper and obsidian for cutting tools.  I already had a set of new blades and scrapers laying around so I just used those.  A chert-only toolkit would have worked well but I didn't want to crack into a new core.  All tools performed well and incurred some interesting edge damage from the soft pulpy wood of the gourd.  The scraper exhibited polish along the working edge due to use.  The obsidian biface incurred a few snapped corners, small step fractures within negative flake scars where the working edge was thinnest and dull polish along the cutting edges.  The obsidian blade received continuous feathered nibbling along the worked margin.  All told, more edge damage than I expected given the relatively soft composition of the gourd.

Trimming the rough edge with an obsidian blade

Use-wear on obsidian from Brown's Bench, Idaho

Small fire with rocks ready to place within the middle of the heat

Before too long I had a bowl ready to drop hot basalt rocks into for a forest meal.  I used pine wood as fuel and three old basalt hammer stones approximately 6-7cm in diameter for a heat source.  Rabbit chunks, squash, a small onion bulb and a little spice went into the mix.  I alternated one hot stone within the vessel at a time while the other stones remained in the fire.  Water began boiling after the second stone.  My lunch failed to catch fire or break apart...a slight let down in terms of laughing while my lunch exploded.  The rolling boil cooked the rabbit and squash within eight minutes.

Ready for hot rock boiling.  The plant is used to brush ash from the stone.
Now we're cooking!


I guess I have become used to things breaking, getting gashed, burned, stabbed or bludgeoned during tests so the smooth sailing of this foray would have been anticlimactic if the food hadn't have tasted so darn great.  I will definitely be doing this again! Crawfish boil anyone?

Attributes created during cooking. See below.

For those of us that enjoy studying the process of archaeological site formation, here is what was left behind for another time.  Several things are readily apparent:  A) bluish thermal discoloration is evident on the surface of the cooking stones.  B) animal protein is present where you see rusty brown material on the top of the stone.  This occurred as the hot rock seared and stuck to meat within the vessel.  C) recycling of lithic materials is evidenced by pecking along the margin of the stone in the foreground where I used an old hammer stone for a hot rock.  I know where these rocks are, so I'll just return to this site instead of carrying the stones around with me.

Happy hunting

Wednesday, June 4, 2014

No Fish Hook? Testing the Prehistoric Fishing Gorge

Hi all,

I'm finally back to test the tools of our ancestors after taking a break to finish up the PhD process.  As it turns out, the final push to finish the degree takes up a few minutes out of one's day...who would have thought.  All that is done now and I have a chance to play again, so lets go!

I first saw fishing gorges in a book by Te Rangi Hiroa (1930) where he illustrated small pointed sections of bone used for fishing by Samoan Islanders.  I had been curious about this fishing technique for a while and finally gave it a go for myself.

Double wooden fish gorge from the Samoan Islands described by Te Rangi Hiroa.

The concept is relatively simple.  A small piece of bait is placed on a pointed tool such that the gorge is parallel to the line.  The assembly is ingested and then flips perpendicular to the line so it cannot come out of the fish's mouth.  The Samoan Islanders were not the only group to use this method; gorges are found across the world from Europe to the Americas and throughout Asia.  Here are a few additional examples:

Gorge hook illustrated by Te Rangi Hiroa from Rarotonga, Cook Islands.

Bone gorge from Anaro, Itbayat Island (Bellwood and Eusebio, ed. 2013)

 Chumash fish gorge, California coast. UCLA, Fowler Museum of Cultural History


I made an antler gorge with stone tools and a sandstone abraider to the general specifications found in the archaeological record, about 3cm long by 3-4mm wide with a small notch to hold the line.  I baited the line with a section of worm (after my dog pilfered the steak chunks i had also brought).  The line was cast into shallow water and slowly pulled about 3 feet under the surface.

Antler gorge with flake used in production. Use wear on stone consisted of edge polish and discontinuous nibbling

Tied down and ready to go

So, things worked eventually after a little trial and error.  The antler gorge ended up being too thick in diameter for the species of fish I was after.  The length and diameter of this tool must be tailored to the size of the target prey.  Upon realizing that the antler gorge was slightly too thick for the bluegills that were interested in the bait I simply cut a small twig from a cedar tree and made another gorge.  After I made this adjustment the game was all over, fish after fish took the bait and were easily pulled from the water.  While more fish escape the gorge in comparison to a barbed hook, the method works very well given a little time and adjustment for fish species.  As a cost/benefit trade off though, I made the twig gorge in about 3 minutes and caught 4 fish in 30 minutes.  Needless to say, I caught a healthy meal in less time than it would take me to fashion a barbed bone hook.

Turns out a cedar twig worked best for the size of fish interested in the bait

And another! The deployed gorge is visible perpendicular to the line in the background

They just kept on coming

So there we have it!  Fishing gorges work really well with a little bit of tweaking for target species. Give it a try sometime, and remember to keep the baited hook parallel to the line so it goes into the mouth straight at first.  Give the fish a few seconds to chomp it back into the throat and then simply pull the little meal out of the water.


Bellwood, Peter and Eusebio Dizon (editors)
2013      4000 Years of Migration and Cultural Exchange: The Archaeology of the Batanes Islands,  Northern Phillipines. Terra Australis 40. Australian National University Press, Canberra, Australia. 

Te Rangi Hiroa (Dr. P. H. Buck).
1930      Samoan Material Culture. Bishop Museum, Honolulu.

Wednesday, April 16, 2014

Oblique Transmission

The other day I was lucky enough to spend time with family in the Piney woods of Deep East Texas.  During that time I made a spear with my cousin Bradley and set off on a short romp around the woods. 

While Bradley observed the process that was being demonstrated to him for the first time, I couldn't help but think of role that cultural transmission played in forming patterns of stone tool production throughout the archaeological record. The material record, those artifacts measured by archaeologists, are the “hard parts” of culture (Dunnell 1978) and may be seen as the skeletal remains of culture, akin to bones that are the representation of the human phenotype that survive after death.

Cutting the main shaft and cleaning it prior to straitening

Ready to go!

Cultural transmission occurs when knowledge is passed to others.  There are multiple modes of transmission.  For instance, vertical transmission occurs with parent-offspring teaching.  Oblique transmission describes learning, in this case a craft skill, from a non-parent of the older generation.  If interested, Stephen Shennan (2009) has compiled a great edited volume on cultural transmission and cultural evolution.

In the following study Eerkens and Lipo (2005) focus on the effect of small unintentional changes in the shape of stone points through unbiased transmission from parent to offspring (vertical transmission).  In each subsequent generation a 3% error rate in reproduction is added to the length of a projectile point and is then transmitted to the next generation in a Markov chain manner such that change could be simulated over time. The extent of error could be positive or negative for each generation, meaning potentially longer or shorter points from the previous generation could appear.  The likelihood for length error will behave in a stochastic manner due to unintentional error during unbiased transmission such that projectile length will have a random probability of distribution.  The authors model the process across 400 generations of 10 lineages and allow no interaction or borrowing (horizontal transmission) between traditions of manufacture. 

Figure adapted from Eerkens and Lipo (2005).


The results (Fig 1) show that simple copying error during cultural transmission may cause traditions of manufacture to drift quite far from the original form and may increase or decrease slightly per generation (Eerkens and Lipo 2005:322).

So cheers to oblique transmission, technological innovation and morphological drift! Well done Bradley.   

Out and about in beautiful East TX
Not exactly what we were hunting for, cool to look at though!

Dunnell, R.C. 
(1978).  Archaeological potential of anthropological and scientific models of functoin. In: Dunnell, R.C., Hall. E.S., (eds.), Archaeological Essays in Honor of Irving Benjamin Rouse. Mouton, The Hague, pp 41-73.

Eerkens, J. W. and C. P. Lipo.
(2005). "Cultural transmission, copying errors, and the generation of variation in material culture and the archaeological record." Journal of Anthropological Archaeology 24(4):316-334.

Shennan, S.
(2009).  Pattern and Process in Cultural Evolution. In Pattern and Process in Cultural Evolution. S. Shennan (ed.). Univiersity of California Press. Los Angeles.          

Sunday, March 2, 2014

Handaxes and San Pedro Shootout

Hi all,

Recently, students of a Texas A&M anthropology course processed animals with Acheulean handaxes and also observed projectile point penetration on fresh animal hide.  I made the handaxes from chert nodules that I liberated from parking lot medians here in town and the San Pedro points from quartzite and obsidian.  Students conducted many other tests, including skeletal damage cause by blunt force trauma and burn patterning on animal bone.

Beginning in Africa. ca. 1.7 mya, and extending until ca. 100,000 years ago, Acheulean handaxes were in use for a staggering amount of time.  The production and use of these teardrop-shaped tools and associated flakes extends from South Africa to Northern Europe and Asia.  The Acheulean technological complex focused on the production of large cutting tools such as bifaces, large flake tools and large cleavers.  For this study we tested differences in applicability between a handaxe and the flakes produced during manufacture for the task of fleshing and separating sections of a carcass.  The flakes removed to produce the handaxe offered precision cutting tools while the resultant axe provided a sharp and heavy implement for separating joints and crushing bone to collect marrow.      

Students use Acheulean handaxes and observe cut mark patterning

For the next test we set out to see how San Pedro points perform as armed darts.  I have a bit of a soft spot for these after seeing one positioned over a much later stone-sealed offering pit in New Mexico.  The ease of production, durability and wide cutting edge makes this morphology especially attractive.  The darts performed quite well and roared through the fresh sheep hide without issue.  However, going home with a handful of unbroken darts would be boring so we kept shooting until the points broke.  The quartzite point was by far the most robust projectile, no surprise there.  The obsidian points performed well and left very clean puncture wounds.  The barbs created by the notched corners functioned fantastically well, so much so that the darts had to be pulled out through the target from the back.

The arrow I had made from river cane growing in the backyard felt better than the shorter version I had made the week prior.  The added length kept the foreshaft joint off of my hand while at full draw.  This arrow flew true and had no issue passing through fresh hide.

Lower half of target had hide and rib sections for impact tests. Upper portion had hide on cardboard backing
Arrow made from backyard river cane with turkey feathers
This Tularosa Corner Notched (ca.1100 B.P.) on composite arrow performed well

First in a set of San Pedro points ready for flight test (Southwest U.S.,ca. 3500-1700 B.P.) .

Quartzite San Pedro #1 impact on bone through hide
Dart #2, hafted obsidian San Pedro point
San Pedro #2 through sheep hide
Surprisingly, San Pedro #2 split through this branch with minimal tip damage

San Pedro #2 eventually struck bone directly under the hide and shattered

San Pedro #3
San Pedro #3 damaged tip after a few ground impacts and a glancing strike on bone through hide
This Pueblo Side Notched arrow point still pushed through after three resharpening events

Saturday, February 22, 2014

Making and Breaking

Hi all,

For the last few weeks I have been producing projectile points and armed darts for a Texas A&M course focused on taphonomic processes.  This course, led by Dr. Darryl de Ruiter, illustrates how animal bones found in the prehistoric record offer evidence of human behavior and natural post-depositional processes.  For instance, differences in impact damage from projectile points and cut marks on bone from butchering may show changing subsistence strategies over time.  We have used stone-tipped arrows, atlatl darts, metal spears...all sorts of fun sharp things.

My part in all of this is to provide a healthy supply of projectile points and other stone tools for use in these experiments.  I have been having a blast and thought I would share what we have been up to so far.

As always, it's been fun to make functional points and destroy them.

Producing stone tools with students for a butchering experiment
Angela Gore testing obsidian point damage on bone
Antler composite point without  binding or inset blades

The durability of this point style surprised us all

Antler point damage from impact with bone

Hafted Folsom point ready for impact damage test
Impact damage from cow head on Folsom
Similar damage pattern on Folsom from Kincaid Shelter, TX. Photo:

This Folsom point passed through the throat with no trouble
Josh Lynch launching a Folsom point. Look at the flex in that dart!
Clovis point wrapped and ready
Clovis point entrance wound

Clovis point impact damage on cow bone