Cranial capacity

Cranial capacity is a measure of the volume of the interior of the cranium (also called the braincase or brainpan) of those vertebrates who have both a cranium and a brain. The most commonly used unit of measure is the cubic centimetre or cc. The volume of the cranium is used as a rough indicator of the size of the brain, and this in turn is used as a rough indicator of the potential intelligence of the organism. However, larger cranial capacity is not always indicative of a more intelligent organism, since larger capacities are required for controlling a larger body, or in some cases are an adaptive feature for life in a colder environment^{[citation needed]}.

Neurological functions are determined more by the organization of the brain rather than the volume. Individual variability is also important when considering cranial capacity, for example the average Neanderthal cranial capacity for females is 1300 cc and 1600 for males (Stanford, 2009, 301). In an attempt to use cranial capacity as an objective indicator of brain size, the encephalization quotient (EQ) was developed in 1973 by Harry Jerison. It compares the size of the brain of the specimen to the expected brain size of animals with roughly the same weight (Campbell et al., 2006, 346). This way a more objective judgement can be made on the cranial capacity of an individual animal.

Examples of cranial capacity:

• Orangutans: 275–500 cc
• Chimpanzees: 275–500 cc
• Gorillas: 340–752 cc
• Humans: 1100–1900 cc
• Neanderthals: 1200–1850 cc

Examples of early hominids:

Taxon	Size (cc)	Number of specimens	Age (megannum)
Australopithecus afarensis	438	4	3.6–2.9
Australopithecus africanus	452	7	3.0–2.4
Paranthropus boisei	521	1	2.3–1.4
Paranthropus robustus	530	1	1.9–1.4
Homo habilis	612	6	1.9–1.6
Homo rudolfensis	700[1]	1	2.4–1.6
Homo ergaster	871	3	1.9–1.7

See also

• Brain-to-body mass ratio
• Craniometry
• Human evolution
• Neuroscience and intelligence

References

1. ^ Bromage TG, McMahon JM, Thackeray JF, et al. (2008). "Craniofacial architectural constraints and their importance for reconstructing the early Homo skull KNM-ER 1470". The Journal of Clinical Pediatric Dentistry 33 (1): 43–54. PMID 19093651. 

Stanford, C., Allen, J.S., Anton, S.C., Lovell, N.C. (2009). Biological Anthropology: the Natural History of Humankind. Toronto: Pearson Canada.

Campbell, G.C., Loy, J.D., Cruz-Uribe, K. (2006). Humankind Emerging: Ninth Edition. Boston: Pearson.

This anatomy article is a stub. You can help Wikipedia by expanding it.v · Categories: Nervous system Anthropology Anatomy stubs Wikimedia Foundation. 2010. Игры ⚽ Поможем написать реферат Eddie LeBec Spirit of place Look at other dictionaries: cranial capacity — n the cubic capacity of the braincase estimated for the living by a formula based on head measurements and determined for the skull by filling the cranial cavity with particulate material (as mustard seed or small shot) and measuring the volume… …   Medical dictionary cranial capacity — noun : the cubic capacity of the braincase estimated for the living by a formula based on head measurements and determined for the skull by filling the cranial cavity with particulate material (as mustard seed or small shot) and measuring the… …   Useful english dictionary Capacity — is the ability to hold, receive or absorb, or a measure thereof, similar to the concept of volume.Capacity may also refer to: *Capacity (economics), the point of production at which a firm or industry s average (or per unit ) costs begin to rise …   Wikipedia Cranial cavity — Body cavities Cranial cavity …   Wikipedia Cranial vault — Sagittal section of a human skull, showing the cranial vault The cranial vault is the space in the skull within the neurocranium, occupied by the brain. In humans, the size and shape of the brain, may be affected by the size of the vault as shown …   Wikipedia Cranial nerve X — The tenth cranial nerve, and one of the most important, is the vagus nerve. All twelve of the cranial nerves, the vagus nerve included, emerge from or enter the skull (the cranium), as opposed to the spinal nerves which emerge from the vertebral… …   Medical dictionary Cranial nerve, tenth — The tenth cranial nerve, and one of the most important, is the vagus nerve. All twelve of the cranial nerves, the vagus nerve included, emerge from or enter the skull (the cranium), as opposed to the spinal nerves which emerge from the vertebral… …   Medical dictionary capacity — 1. The potential cubic contents of a cavity or receptacle. 2. Power to do. SEE ALSO: volume. [L. capax, able to contain; fr. capio, to take] buffer c. the amount of hydrogen ion (or hydroxyl ion) required to bring about a specific pH change in a… …   Medical dictionary Tenth cranial nerve — The tenth cranial nerve, and one of the most important, is the vagus nerve. All twelve of the cranial nerves, the vagus nerve included, emerge from or enter the skull (the cranium), as opposed to the spinal nerves which emerge from the vertebral… …   Medical dictionary Nerve, tenth cranial — The tenth cranial nerve, and one of the most important, is the vagus nerve. All twelve of the cranial nerves, the vagus nerve included, emerge from or enter the skull (the cranium), as opposed to the spinal nerves which emerge from the vertebral… …   Medical dictionary 18+ © Academic, 2000-2024 Contact us: Technical Support, Advertising Dictionaries export, created on PHP, Joomla, Drupal, WordPress, MODx. Mark and share Search through all dictionaries Translate… Search Internet Share the article and excerpts Direct link … Do a right-click on the link above and select “Copy Link”