Archaeological Science

Archaeological science is the integration of scientific analysis and principles in investigating archaeological finds. Though science and archaeology have had a 200 year old relationship, the mainstream inclusion of hard science in archaeology began in the systematic approaches of the so-called ‘New Archaeology’ of the 1960s.^[1] This movement, otherwise known as ‘Processual Archaeology’ promoted a cross-disciplinary approach in interpreting and analysing physical remains.

Excavated remains can include metals, lithics and organic material like bones and shells. A thorough evaluation of their physical and chemical properties helps immensely in inferring the motivation, cognition and behaviour of ancient populations ^[2]. Scientific application in archaeology thus incorporates the full range of natural sciences like physics, chemistry and biology. 

Types of Archaeological Science

Environmental Archaeology

• Geoarchaeology is the discipline that thoroughly examines the nature of landscapes and formation of a site.^[1] It applies stratigraphy, sedimentology and analyses the mineral as well as physical composition of soils and rocks present in lithic tools as well as the excavated land.
• Zooarchaeology identifies and taxonomically classifies animal remains found during excavations. This helps understand past human-animal relationships with regard to domestication and animal-based diets etc. Remains commonly include and aren’t limited to horses, pigs and cattle. 
• Archaeobotany or paleoethnobotany, the sub-discipline that investigates floral remains found in archaeological contexts. Grains, nuts and charred seeds and incipient wild species are identified. Pollen grains (palynology) and phytoliths^[3] are also used to determine the species of ancient plants and their relationship with past humans. Residues from cooking pots (starch analysis) are also scanned to infer past culinary habits.^[4]

Bioarchaeology

• Human osteology is a discipline that studies human bone assemblages. It makes use of biological anthropology to estimate the age, sex and ethnicity of the individuals found. Moreover, paleopathology of bones can detail the health-related aspects of past demographics including diseases and nutrition. These remains are commonly discovered at burial sites. 
• Isotope analysis is used on dental and bone remains to ascertain the dietary patterns of the past using carbon (collagen) and nitrogen isotopes. The use of strontium isotope from tooth enamel can indicate the birthplace of an individual, thereby conveying any migration activity done in his/her lifetime. 
• (aDNA) Ancient DNA analysis has been monumental in reconstructing past population histories, genetic heritage and ancestry. aDNA also helps calibrate molecular clocks which measure the rates of evolution in different species. ^[5]

Archaeological chemistry

This branch of archaeological science is involved in material analysis of ceramics, glassware, metals and lithics found in excavations. It uses methods like X-ray diffraction (XDR), Scanning Electron Microscope (SEM) and petrographic analysis to study the mineral content and raw materials in pottery sherds and lithic tools or artifacts. 

Additionally, since excavations are done in soil contexts, archaeological chemistry evaluates its organicity and nature in extensive soil analysis experiments. 

Metals like copper (coins, ornaments) and iron objects are cleaned in archaeochemistry procedures. This helps in their identification, conservation and preservation. 

Remote Sensing Technology

In recent times, archaeology has been greatly influenced by advances in technology like GPS and satellite imagery. Remote sensing allows retrieval of information regarding objects on the ground and surface landscapes by the use of mounted sensors on aircrafts. Ground Penetrating Radars and LiDars use radio and light waves respectively, to detect and collect information about the surface. Such technologies, albeit expensive, give detailed information about the geo-spatial aspects of the ground and help in site survey as well as selection.

Age-determination and Dating

Archaeological science has enabled absolute dating of archaeological sites and excavated artifacts. Radiocarbon dating is a highly scientific process based on the unstable 14C isotope and can effectively measure dates up to >40,000 years ago.^[6] It has helped in suggesting the replacement of Neanderthals by modern humans. 

Additionally, Luminescence dating is another elaborate scientific dating technique which is based on the absorption of radiation by minerals and lithics. This radiation can be measured by heating (Thermoluminescence) and by illumination (OSL method). 

Age determination has seen the advent of advanced technology like Accelerator Mass Spectrometry which has paved the way for faster, more accurate and cost-effective dating.^[7]

Conclusion

To summarise, the importance of hard science in archaeology is addressed. Its implications in systematic analysis of artifactual evidence is highlighted. Scientific archaeology or archaeometry, has allowed absolute dating of excavated remains and sites which are crucial in placing them within historical contexts. Some of the methods in archaeological science are destructive and raise ethical questions regarding the same. Overall, the discipline has a broad scope and houses an array of techniques and sub-disciplines which all contribute to scientific understanding in archaeological studies.

See Also

References

[1] Archaeological Science: An Introduction. (2020). India: Cambridge University Press.

[2] Rich, L. E. 2015. ‘Leapin’ lizards, Mr. Science’: Old reflections on the new archaeology (and musings on anthropology, art, bioethics, and medicine). Journal of Bioethical Inquiry 12(4):531–535.

[3] Bryant, V. M., Jr. and Holloway, R. G. 1983. The role of palynology in archaeology. In: Schiffer, M. B. (ed.) Advances in Archaeological Method and Theory, Vol. 6, pp. 191–223. New York: Academic Press.

[4] Torrence, R. 2006b. Starch in sediments. In: Torrence, R. and Barton, H. (eds.) Ancient Starch Research, pp. 145–176. Walnut Creek, CA: Left Coast Press.

[5] Palkopoulou, E., Mallick, S., Skoglund, P., Enk, J., Rohland, N., Li, H., Omrak, A., Vartanyan, S., Poinar, H., Götherström, A., and Reich, D. 2015. Complete genomes reveal signatures of demographic and genetic declines in the woolly mammoth. Current Biology 25(10):1395–1400.

[6] Geyh, Mebus A., and Helmut Schleicher. 1990. Absolute Age Determination: Physical and Chemical Dating Methods and Their Application. Translated by Clark Newcomb. N.p.: Springer Berlin Heidelberg.

[7] Harris, D. R.; Gove, H. E.; Damon, P. (1987). The Impact on Archaeology of Radiocarbon Dating by Accelerator Mass Spectrometry [and Discussion]. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 323(1569), 23–43. doi:10.1098/rsta.1987.0070