Chapter 5. Field Methods in Archaeology and Paleoanthropology. Chapter Preview. How Are the Physical and Cultural Remains of Past Humans Investigated? Are Human Physical and Cultural Remains Always Found Together? How Are Archaeological or Fossil Remains Dated?. Prehistory and History.
Field Methods in Archaeology and Paleoanthropology
The only way to thoroughly investigate our past is to excavate (dig) sites where biological and cultural remains are found.
The fundamental premise of excavation is that all digging is destructive, even that done by experts. The archaeologist’s primary responsibility, therefore, is to record a site for posterity as it is dug because there are no second chances.
- Brian Fagan, archaeologist
What kinds of information can we get from recording a site?
ANSWER – Material Culture and Skeletal Remains/Fossils
The term material culturerefers to the durable aspects of culture such as tools, structures, and art.
Is this example of one of the Nazca Lines in Peru a feature, artifact, ecofact or manuport?
Are these examples of Maya sculpture features, artifacts, ecofacts or manuports?
Look over this list of material objects and decide if they are artifacts, manuports, ecofacts, or features:
1. A lucky rabbit’s foot
2. Bones of a dairy cow
3. A stepped-pyramid
4. A stone tool
5. A hearth or ring of stones
Since excavations are destructive, archaeologists must carefully record the location of material remains in three-dimensional space.
Which material remain is older?
Excavation records include a scale map of all the features, the stratification of each excavated square, a description of the exact location and depth of every artifact or bone unearthed, and photographs and scale drawings of the objects.
In the lab, artifacts that have been recovered from an excavation must be cleaned and catalogued before they are ready for analysis.
From the shapes of the artifacts as well as from the traces of manufacture and wear, archaeologists can usually determine their function.
(1) Endocasts - Casts of the inside of a skull which can help determine the size and shape of the brain.
(2) Coprolites - Preserved fecal material providing evidence of the diet and health of past organisms.
(3) Small fragments of DNA can be amplified or copied repeatedly using polymerase chain reaction (PCR) technology to provide a sufficient amount of material to perform these analyses.
The termbioarchaeologyrefers to the archaeological study of human remains emphasizing the preservation of cultural and social processes in the skeleton.
Examples include: forensic anthropology, human osteology, and paleopathology.
(1) determine the sex, age (at death), and ancestral population of a skeleton from morphological features
(2) determine wear patterns on the bones and teeth from repeated activities
(3) comparison with other skeletons to determine species affiliation
- Trauma in skeletons is clearly evident in bone fractures, especially when they have not healed successfully.
- The individual workload leaves traces in the skeleton.
- Growth-disrupting and growth-retarding stresses during childhood will leave transverse lines of dense bone visible in radiographs of long bones of the body.
Tibias from a 50-60 year old Roman Soldier, 3rd-4th Century, AD
Spear injury to right tibia
Osteoporosis on both tibias
Patellas of a 40 year old Moche potter (350-600 AD)
Both show wear from extended periods of kneeling
Female Skull, 500 AD
Blunt force trauma to left side of the face
Male Skull, Belize, Postclassic Period (1300 AD)
Possible anemia or syphilitic infection
Yde Girl – a bog body from the Netherlands
(1st Century AD)
Hair has been cut off
Evidence of strangulation or hanging
Skulls with evidence for cranial re-shaping
As scientists, anthropologists know the importance of the information that can be gleaned from studies of human skeletons, but as scholars subject to ethical principles, they are bound to respect the feelings of those who give skeletons a deep cultural and spiritual significance.
(1) relative dating - designating an event, object, or fossil as being older or younger than another.
(2) absolute or chronometric dating – provides dates for recovered material based on solar years, centuries, or other units of absolute time.
Seriation = a technique for relative dating by putting groups of objects into a sequence in relation to one another.
Stratigraphy = a technique for relative dating based on organizing remainsby means of strata. Objects in lower strata are older than objects in higher strata.
Palynology = a method of relative dating based on changes in fossil pollen over time.
Radiocarbon dating = a technique of dating based on measuring the amount of radioactive carbon (14C ) left in organic materials found in archaeological sites.
Dendrochronology= a method of dating based on the number of rings of growth found in a tree trunk.
Potassium-argon dating = a method of absolute dating based on measuring the amount of radioactive potassium left in a layer of volcanic rock.
Electron spin resonance = measures the number of trapped electrons in bone
Thermo-luminescence = measures the amount of light emitted from a specimen when heated to high temperatures.