Module 6 - Forensic Anthropology and Forensic Entomology (Bones & Bugs)
Lesson 1 - Determining Ancestry and Sex from Human Skeletal Remains
Using Bones to Determine Ancestry
A forensic anthropologist may be able to help determine the ancestry of a victim through an examination of the skull and other parts of the skeleton. Determining the ancestry of a victim can help law enforcement officials determine the identity of an unknown corpse. Certain common traits can be found in the facial features of the skulls of individuals that share the same ancestry. The human skull has the greatest number of these unique traits.
Some skull characteristics are more common in some ancestral groups than in others. To use three general ancestral groups is common practice: Negroid, Mongoloid, and Caucasoid. However, in the past more than twenty groups have been used.
- Negroid – from the Spanish word meaning “black”; includes African, Caribbean, and African-American ancestry
- Mongoloid – from the word Mongolian; includes those Chinese, Japanese, Inuit and Native ancestry
- Caucasoid – referred to as “white-skinned” or of European descent; originally from the Caucasus region found between the Black Sea and the Caspian Sea; includes Europeans, East Indians, Pakistanis, and Arabs.
The determination of ancestry from skeletal remains is controversial because only a few skull characteristics are unique to one particular ancestral group. In addition, the assessment of ancestry from skeletal remains is not highly reliable because populations are so intermixed today. Consequently, to determine ancestry with any degree of certainty is difficult; thus, forensic anthropologists tend to make suggestions rather than conclusions about which ancestral group may be evident from the skeletal remains they are examining.
"Presently, there is a debate within anthropology concerning the non-existence of race. To avoid this debate and controversy, the terms race and ethnicity are avoided in favor of the term ancestry to describe the genetic background of persons."
- Source: Steven N. Beyers, Introduction to Forensic Anthropology; A Textbook (p. 150). Allyn & Bacon (2002).
Comparison of Cranial Features
Several cranial features have been found to be distinctive in various ancestries. Of primary significance are two regions of the human skull: the orbits and the nasal region. The skull has two orbits that house the eyeballs. The nasal region is the area in and around the nose.
Negroid Ancestry: Cranial Features
Skull of an Individual of Negroid Ancestry
- Image Source: Courtesy the University of Utah Health Sciences Center Osteointeractive website
An individual with Negroid ancestry is more likely to have orbits that are rectangular in shape and a nasal border that is guttered. Additionally, the space between the eyes and nose (interorbital area) tends to be wider than in other groups.
"Forensic anthropologists do not have the luxury of debating the issue of race and ethnicity; rather, they must arrive at an assessment of this demographic characteristic to aid the police in their identification process."
- Source: Dr. Steven N. Byers, Introduction to Forensic Anthropology; A Textbook, Allyn and Bacon (2002), p.150.
Caucasoid Ancestry: Cranial Features
Skull of an Individual of Caucasoid Ancestry
- Image Source: Courtesy of the University of Utah Health Sciences Center Osteointeractive website
An individual with Caucasoid ancestry tends to have orbits that are sloped. Another distinct feature of Caucasoid individuals is the prominent nasal spine and steepled nasals.
"It is clear that race does mean different things to different people. In the context of forensic anthropology, the term race is unambiguous."
- Source: Dr. Stanley Rhine, Ph.D. (Forensic Anthropologist – University of New Mexico)
Mongoloid Ancestry: Cranial Features
Skull of an Individual of Mongoloid Ancestry
- Image Source: Courtesy of the University of Utah Health Sciences Center Osteointeractive website
An individual with Mongoloid ancestry tends to have round orbits. Often the base of the nasal area of mongoloid individuals is flared meaning that it appears to widen.
Prehistoric skeletal remains that have been formally buried are most often found lying in the fetal position with knees drawn up to the chest, while skeletons from remains buried during modern times, especially those from industrialized countries, are most often found lying on their backs with their limbs extended straight.
- Source: Steven N. Beyers, Introduction to Forensic Anthropology; A Textbook (p. 78-79). Allyn & Bacon (2002).
The student will…
- recognize that in the field of forensic anthropology information about the victim of a crime and the nature of the crime itself is determined from unknown skeletal remains
- understand that a forensic anthropologist attempts to determine the following information from unknown skeletal remains: whether the remains are human or non-human, number of individuals found, time of death, sex of individual(s), ancestry of individual(s), stature of individual(s), and cause of death
- describe some of the basic skeletal differences between human and animal bones (such as ribs and upper and lower limbs)
- state some of the basic skeletal differences between humans from various ancestries or races (such as Negroid, Caucasoid, Mongoloid)
- identify some of the basic skeletal differences between female and male remains
- perform a research study that compares the size and length of various bones in males and females
Cranial
- The skull or pertaining to the skull
Corpse
- A dead body; used to refer specifically to a human body in the early period after death
Negroid
- Of, constituting, or characteristic of a race of humankind native to Africa and classified according to physical features; having dark skin pigmentation
Mongoloid
- Of, constituting, or characteristic of a race of humankind native to Asia and classified according to physical features
Caucasoid
- (Caucasian): of, constituting, or characteristic of a race of humankind native to Europe, North Africa, and Southwest Asia and classified according to physical features; usually with lighter skin colour
Orbits
- Referring to the two openings in the skull that contain the eyeballs
Nasal
- Pertaining to the nose
Guttered
- Marked with a wide, shallow groove or grooves
Steepled
- Tapered to a point at the top