Additional Comments on Blood Residue and Analysis in Archaeology

Article excerpt

In the March Antiquity, Eisele et al. (1995) presented immunological results from prehistoric sites, and from simulated archaeological contexts, which suggest that residues will not survive on prehistoric stone tools. Over the last several years, we have submitted over 200 archaeological items to a commercial laboratory for immunological residue analysis. In an effort to evaluate the reliability of these archaeological results, we initiated an actualistic test using experimentally generated artefacts coated with blood of known animals. Here, we present results for n of these experimental samples. Our results also suggest that archaeologists should view immunological results with caution.

The 54 experimental samples reflect a variety of artefact types and materials encountered archaeologically. Using 10 species of animals collected from recent road kills and commercial butchers, we coated freshly knapped artefacts with blood by cutting and scrapping a specimen for several minutes. After allowing the artefacts to dry, we removed visible hairs from several of the specimens by wiping them with a cotton cloth or lightly rubbing them with sand. However, in almost all cases blood was still visible macroscopically, and it is our opinion that this procedure did not remove the blood from any specimens. Several `blank' lithic tools and sediment samples, along with sediment and fire-cracked rock (FCR) samples from an experimental hearth used to cook a rabbit, were also submitted for analysis.

All experimental samples were sent to a commercial laboratory that uses a gel immunoelectrophoresis technique, crossover immunoelectrophoresis (CIEP). Complete details of this technique, and its application to archaeological materials, are presented by Newman & Julig (1989). The experimental samples were tested against a series of polyclonal antiserum, including those for bovine, chicken, deer, dog, elk, guinea-pig, human, pronghorn, rabbit, rat, turkey, beans, corn, mesquite, pinyon, squash and yucca.

Results, reported by the laboratory (Table 1) fall into five groups: * the laboratory correctly identified the blood of the animal, or did not report any blood on a blank sample., * the laboratory correctly identified the blood of the primary animal, but also noted the blood of other animals., * the animal was correctly identified, but not as the primary blood on the item., the laboratory reported the blood of the wrong animal; * no blood was detected though blood was present.

Table 1. Experimental animals and results.

      artefact          experimental       laboratory
      type               residue           results

1     lithic tool        human             human
2     lithic tool         elk              deer, elk, human
3     lithic tool         elk              deer, elk
4     lithic tool         elk              deer, elk, human
5     lithic tool         elk              human, deer, elk
6     lithic tool        squirrel          negative
7     lithic tool        squirrel          negative
8     lithic tool         mouse            deer, elk
9     lithic tool         mouse            human
10    lithic tool         coyote           negative
11    lithic tool         coyote           negative
12    lithic tool         bobcat           negative
13    lithic tool         bobcat           negative
14    lithic tool         bobcat           negative
15    lithic tool          deer            deer, elk
16    lithic tool          deer            deer, elk, human
17    lithic tool          deer            deer, elk
18    lithic tool          blank           negative
19    lithic tool          blank           negative
20    lithic tool          lank            human
21    lithic tool          blank           negative
22    lithic tool          blank           negative
23    lithic tool          blank           negative
24    lithic tool          blank           negative
25    lithic tool           cow            bovine, elk
26    lithic tool           cow            bovine
27    lithic tool          turkey          negative
28    lithic tool          turkey          chicken
29    lithic tool          turkey          chicken
30    lithic tool          rabbit          human, rabbit
31    lithic tool          rabbit          rabbit
32    lithic tool          rabbit          rabbit
33    lithic tool          rabbit          rabbit
34    lithic tool          rabbit          rabbit
35    lithic tool          rabbit          rabbit
36    lithic tool          rabbit          rabbit, mouse
37    lithic tool          rabbit          turkey
38    lithic tool          rabbit          rabbit
39    lithic tool          rabbit          rabbit
40    lithic tool          rabbit          rabbit
41    lithic tool          rabbit          rabbit
42    lithic tool          rabbit          rabbit
43    lithic tool          rabbit          rabbit
44    lithic tool(1)       rabbit          negative
45    lithic tool(2)       rabbit          negative
46    lithic tool(2)       rabbit          negative
47    lithic tool(2)       rabbit          negative
48    lithic tool(2)       rabbit          negative
49    sediment             blank           negative
50    sediment(3)          rabbit          negative
51    sediment(3)          rabbit          negative
52    sediment(3)          rabbit          negative
53    fire-cracked         rabbit          negative
         rock(3)
54    fire-cracked         rabbit          negative
        rock(3)

1 Artefact heated to 250 [degrees]C for 30 minutes. …