Editing Cephalic index (section)

==Historic use in anthropology==
===Early anthropology===
[[File:Cephalic index map of Europe by Bertil Lundman, 1993.jpg|thumb|Cephalic index map of Europe by Bertil Lundman]]
The cephalic index was used by anthropologists in the early 20th century as a tool to categorize human populations. It was used to describe an individual's appearance and for estimating the age of [[fetus]]es for legal and obstetrical reasons.{{Citation needed|date=January 2025|reason=According to Pfenninger and Fowler's Procedures for Primary Care, Chapter 142 Obstetric Ultrasound, 984-998, the cephalic index remains constant throughout pregnancy and is instead used as a measure of cranial deformity. Need a reference to show it was ever used for the purpose of estimating fetal age}}

The cephalic index was defined by [[Sweden|Swedish]] professor of [[anatomy]] [[Anders Retzius]] (1796–1860) and first used in [[physical anthropology]] to classify ancient human remains found in Europe. The theory became closely associated with the development of [[racial anthropology]] in the 19th and early 20th centuries, when historians attempted to use ancient remains to model population movements in terms of racial categories. American anthropologist [[Carleton S. Coon]] also used the index in the 1960s, by which time it had been largely discredited.

[[File:PSM V59 D404 Cephalic indexes of skull shapes.png|thumb|Cephalic indexes of skull shapes. Long skull (left) – cephalic index 71.4; tall skull (center) – cephalic index 81; broad skull (right) – cephalic index 85]]

In the cephalic index model, human beings were characterized by having either a dolichocephalic (long-headed), mesaticephalic (moderate-headed), or brachycephalic (short-headed) cephalic index or cranial index.
[[File:Otmaa1917 1-1-.jpg|thumb|The children of the Tsar [[Nicholas II of Russia]] in June 1917, with loss of hair after fighting [[measles]]: among them, [[Grand Duchess Tatiana Nikolaevna of Russia|Tatiana]] had the skull with least cephalic index.]]

===Indices===
[[File:PSM V50 D602 World cephalic index map.jpg|thumb|1896 world cephalic index map]]
Cephalic indices are grouped as in the following table:

{| class="wikitable"
|-
! Females !! Males !! Scientific term !! Meaning !! Alternative term
|-
| < 75 || < 75.9  || ''dolichocephalic'' || 'long-headed' ||
|-
| 75 to 83 || 76 to 81 || ''mesaticephalic'' || 'medium-headed' || ''mesocephalic''; ''mesocranial''
|-
| > 83 || > 81.1 || ''brachycephalic'' || 'short-headed' || ''brachycranial''
|}

Technically, the measured factors are defined as the maximum width of the bones that surround the head above the [[Temporal bone|supramastoid crest]] (behind the cheekbones), and the maximum length from the most easily noticed part of the [[Frontal bone|glabella]] (between the eyebrows) to the most easily noticed point on the back part of the head.

===Controversy===

The usefulness of the cephalic index was questioned by the Italian anthropologist [[Giuseppe Sergi]], who argued that cranial morphology provided a better means to model racial ancestry.<ref>{{cite thesis| vauthors = Killgrove K |year=2005 |title=Bioarchaeology in the Roman World | degree = Masters | publisher = UNC Chapel Hill |url=http://www.piki.org/~kristina/Killgrove-2005-classics.pdf |archive-url=https://web.archive.org/web/20120328162246/http://www.piki.org/~kristina/Killgrove-2005-classics.pdf |archive-date=28 March 2012 |url-status=dead}}</ref> Also, [[Franz Boas]] studied the children of immigrants to the United States in 1910 to 1912, noting that the children's cephalic index differed significantly from their parents', implying that local environmental conditions had a significant effect on the development of head shape.<ref name="Holloway_2002">{{cite journal | vauthors = Holloway RL | title = Head to head with Boas: did he err on the plasticity of head form? | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 99 | issue = 23 | pages = 14622–3 | date = November 2002 | pmid = 12419854 | pmc = 137467 | doi = 10.1073/pnas.242622399 | bibcode = 2002PNAS...9914622H | doi-access = free }}</ref>

Boas argued that if craniofacial features were so malleable in a single generation, then the cephalic index was of little use for defining race and mapping ancestral populations. Scholars such as [[Earnest Hooton]] continued to argue that both environment and heredity were involved. Boas did not himself claim it was totally plastic.

In 2002, a paper by Sparks and Jantz re-evaluated some of Boas's original data using new statistical techniques and concluded that there was a "relatively high genetic component" of head shape.<ref>{{cite journal | vauthors = Sparks CS, Jantz RL | title = A reassessment of human cranial plasticity: Boas revisited | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 99 | issue = 23 | pages = 14636–14639 | date = November 2002 | pmid = 12374854 | pmc = 137471 | doi = 10.1073/pnas.222389599 | doi-access = free | bibcode = 2002PNAS...9914636S }}. See also the discussion in {{cite journal | vauthors = Holloway RL | title = Head to head with Boas: did he err on the plasticity of head form? | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 99 | issue = 23 | pages = 14622–14623 | date = November 2002 | pmid = 12419854 | pmc = 137467 | doi = 10.1073/pnas.242622399 | doi-access = free | bibcode = 2002PNAS...9914622H }}</ref> Ralph Holloway of Columbia University argues that the new research raises questions about whether the variations in skull shape have "adaptive meaning and whether, in fact, normalizing selection might be at work on the trait, where both extremes, hyperdolichocephaly and hyperbrachycephaly, are at a slight selective disadvantage."<ref name="Holloway_2002"/>

In 2003, anthropologists Clarence C. Gravlee, H. Russell Bernard, and William R. Leonard reanalyzed Boas's data and concluded that most of Boas's original findings were correct. Moreover, they applied new statistical, computer-assisted methods to Boas's data and discovered more evidence for cranial plasticity.<ref name=Gravlee>{{cite journal| vauthors = Gravlee CC, Bernard HR, Leonard WR |title=Heredity, environment, and cranial form: A reanalysis of Boas's immigrant data|journal=American Anthropologist|date=March 2003|volume=105|issue=1|pages=125–138|doi=10.1525/aa.2003.105.1.125|url=http://www.gravlee.org/files/pdfs/gravlee03a.pdf|access-date=2018-03-23|hdl=2027.42/65137|archive-url=https://web.archive.org/web/20140730140427/http://www.gravlee.org/files/pdfs/gravlee03a.pdf|archive-date=30 July 2014|url-status=usurped|hdl-access=free}}</ref> In a later publication, Gravlee, Bernard and Leonard reviewed Sparks's and Jantz's analysis. They argue that Sparks and Jantz misrepresented Boas's claims, and that Sparks's and Jantz's data support Boas. For example, they point out that Sparks and Jantz look at changes in cranial size in relation to how long an individual has been in the United States in order to test the influence of the environment. Boas, however, looked at changes in cranial size in relation to how long the mother had been in the United States. They argue that Boas's method is more useful, because the prenatal environment is a crucial developmental factor.<ref name=Gravlee/>

Jantz and Sparks responded to Gravlee et al., reiterating that Boas' findings lacked biological meaning, and that the interpretation of Boas' results common in the literature was biologically inaccurate.<ref>{{cite journal | vauthors = Sparks CS, Jantz RL  |title=Changing Times, Changing Faces: Franz Boas's Immigrant Study in Modern Perspective |journal=American Anthropologist |volume=105 |issue=2 |year=2003 |pages=333–337 |doi=10.1525/aa.2003.105.2.333 }}</ref> In a later study, the same authors concluded that the effects Boas observed were likely the result of population-specific environmental effects such as changes in cultural practices for cradling infants, rather than the effects of a general "American environment" which caused populations in America to converge to a common cranial type, as Boas had suggested.<ref>{{cite journal | vauthors = Jantz RL, Logan MH | title = Why does head form change in children of immigrants? A reappraisal | journal = American Journal of Human Biology | volume = 22 | issue = 5 | pages = 702–707 | year = 2010 | pmid = 20737620 | doi = 10.1002/ajhb.21070 | s2cid = 12686512 }}</ref><ref>{{cite book | vauthors = Spradley MK, Weisensee K |chapter=Ancestry Estimation: The Importance, The History, and The Practice | veditors = Langley NR, Tersigni-Tarrant MT |title=Forensic Anthropology: A Comprehensive Introduction |edition=Second |year=2017 |pages=165–166 |publisher=CRC Press |isbn=978-1-4987-3612-1 }}</ref>