What We Work On

PROTEIN RESIDUE COLLECTION MANUAL
Paleo Research Institute
2675 Youngfield St.
Golden, Colorado 80401
(303) 277-9848

COLLECTION OF FIELD SPECIMENS

Flaked Lithics

All flaked lithic specimens should be placed directly into ziplock/whirl-pak bags with minimal handling.
Please do not spit, lick, or rub on the artifacts as this may result in positive results for human proteins.
Label the outside of the bag and if desired, place a second label inside the bag.

Control Samples

Since false positives may result from bacteria, animal feces, lippoproteins, and alkaline substances
in the soil, it is necessary to test soil samples with the artifacts. Collect approximately 1 gram samples
from soil surrounding the artifacts and place in suitable containers (film canisters work nicely).
Other control samples:

  • Stratified sites: Collect 1 gram samples from all cultural levels andfrom at least one, but no more thanthree, off-site areas.
  • Surface sites: Collect 1 or 2 one gram samples from the site as well
    as 1 sample from off-site.

Control samples will be processed at our discretion and at no additional cost.

Groundstone and Pecked Stone

This category includes manos, mortars, pestles, etc. We prefer that groundstone and pecked stone artifacts be sent to our laboratory for extraction, especially if pollen and/or phytolithanalyses are also requested. We will collect a protein residue sample from one side or area of the groundstone and pollen/starch and/or phytolith samples from a separate area of the ground surface. Starch granules represent starchy foods such as seeds and roots/tubers that often are ground in preparation for cooking.

Extracts for protein residue analysis from large metates or bedrock mortars should be collected by the archaeologist in the lab or field using the methods on page 4.

Ceramics

Ceramics can also be tested for protein residue, pollen, starch, and/or phytoliths. Whole pots or sherds can be sent for analysis and will be treated in a similar manner as groundstone. Protein residue analysis cannot be used on carbonized materials as the protein proteins are too severely denatured to yield results. Ceramics containing visible residue are excellent candidates for phytolith analysis using a new technique that can distinguish phytoliths of wild grasses from those of Zea mays and also can identify variety of maize.

Soils

Soils from suspected processing areas and/or kill sites frequently retain the blood of the animal(s) processed. These soils can also be tested. Small (1 gram) amounts of the soil(s) to be tested should be placed in a ziplock/whirl-pak bag or clean film canister and sent for analysis.

Curated Artifacts

Curated artifacts are also possible candidates for protein residue analysis. If the curated artifacts are stored in trays, they should be placed in separate, labeled ziplock/whirl-pak bags. If these artifacts are stored in other types of bags, such as brown paper, please send them in "as is."

ARTIFACT SELECTION/RESEARCH QUESTIONS

For very large collections of lithics, selection of artifacts sent for protein residue analysis should fit the research design. Some examples:

Finished tools, projectile points with impact fractures, flakes with obvious use/wear.

Specific classes of artifacts. For example, were projectile points of one class used on a single type of animal -- large points for large game, small points for small animals?

If artifacts were multi-purpose tools, it is sometimes possible to identify more than one type of protein residue, unless the animals are closely related such as sheep and goats, or deer and elk.

Different types of protein residue may be detected from the hafting area and from the tip of the same tool. Identification of proteins from the hafting area may identify the hafting medium. When sending artifacts for hafting area AND tip analysis, please indicate that each area is to be tested separately. These areas are considered to be two separate samples and will be charged as two samples.

Protein residue analysis can be used in evaluating different aspects of prehistory.
Examples in which it may be of benefit are:

1. As an objective test of tool function

2. As a test to determine whether animals represented in faunal remains were processed at the site.

3. To determine a possible range of animal resources exploited.

Reports

Our reports are interpretive, rather than providing just a list of positive reactions.
We identify possible animals represented by positive results based on known
distributions of the animals and known and tested reactions of the antisera.

Artifacts sent for analysis can be tested against the following antisera:

Bear

Deer

Pig

American eel

Trout

Agave (includes
yucca & aloe)

Bison

Dog

Rabbit

Atlantic croaker

White perch

Acorn

Bovine

Goat

Rat

Bay anchovy

   

Camel

Guinea pig

Sheep

Catfish

   

Cat

Horse

Turkey

Gizzard shad

   

Chicken

Human

Elephant(mammoth)

Striped bass

   

Protein residue analysis has been successfully applied to archaeological materials from a variety of areas including Arizona, California, Colorado, Idaho, Montana, Nevada, New Jersey, New Mexico, Pennsylvania, and Texas.

COLLECTING PROTEIN RESIDUE SAMPLES FROM GROUNDSTONE

Extraction of protein residues is usually performed with a 0.2 M Tris hydrochloride, 0.5 M sodium chloride, and 0.5 % Triton X-100 solution (most desirable), although a 5 % ammonium hydroxide solution (less desirable) also can be used. The components for these solutions can be purchased from Fisher Scientific and from Sigma Chemical Company. When washing groundstone, use as little solution as possible (1-5 mL). For an additional $10.00 charge, we can use a Centriprep-10 centrifugal concentrator with a 10,000 molecular weight cut-off membrane. This allows us to concentrate the proteins in a large volume of liquid down to a sample about 1-2 mL in size. If you opt to use the Centriprep device, a larger volume of solution may be used to wash the artifact (up to 50 mL).

Using a sterile (new) toothbrush, vigorously scrub the surface of the groundstone where a small amount of solution was applied. Decant the liquid using a pipette or syringe and repeat until a small area of the ground surface has been cleaned. Use additional solution from the pipette or syringe to "wash" the bristles of the toothbrush to get the residue out of it.

The decanted solution should be placed in a clean (preferably new) screw-capped plastic container with a tight seal. This container should be placed in a labelled ziplock/whirl-pak bag. If you have groundstone that was buried in the soil, be sure to scrape off the excess soil and include a soil control from the same area as the groundstone (preferably not what was scraped off the tool). Soils commonly contain compounds such as bacteria, lippoproteins, and animal feces that can cause false positive results for buried artifacts. A 1-2 gram soil control size is all that is required, and these soil controls are run at no extra charge.

DO THIS PROCEDURE FIRST, BEFORE WASHING THE REMAINDER OF THE SURFACE
FOR POLLEN/PHYTOLITHS/STARCH.

DO NOT USE GLASS CONTAINERS FOR STORING PROTEIN RESIDUES, AS THE
PROTEIN WILL ADHERE TO THE GLASS, MAKING RECOVERY DIFFICULT OR IMPOSSIBLE.

GUIDELINES FOR FIELD COLLECTION OF ARTIFACTS FOR PROTEIN RESIDUE ANALYSIS

In the Field:

1. Handle the artifact as little as possible.

Use trowel to pick up and place in plastic bag

Use powderless latex gloves (other gloves are less effective) (NOTE: any latex or non-latex gloves might contain starch. DO NOT USE if you want Starch Analysis unless you have had the brand of gloves tested for starch.)

2. Do not brush off or clean dirt adhering to artifact

3. Place artifact in clean plastic bag

4. In a separate plastic bag or clean film canister, add a small amount of adjacent dirt

Dirt will be used as a negative control

Dirt should be from under the artifact unless the artifact is in an area suspected to have been filled with blood, guts, and gore.

Dirt should not have touched the artifact in situ

In the Lab:

1. Know the laboratory where analysis is being performed

Do they understand the methods to be used?

What are their handling and extraction methods?

Do they understand the antisera used for analysis?

How will results be reported?

Updated 01-09-06