Skip to main content Accessibility help

Brain evolution in Homo: The “radiator” theory1

  • Dean Falk (a1)


The “radiator” theory of brain evolution is proposed to account for “mosaic evolution” whereby brain size began to increase rapidly in the genus Homo well over a million years after bipedalism had been selected for in early hominids. Because hydrostatic pressures differ across columns of fluid depending on orientation (posture), vascular systems of early bipeds became reoriented so that cranial blood flowed preferentially to the vertebral plexus instead of the internal jugular vein in response to gravity. The Hadar early hominids and robust australopithecines partly achieved this reorientation with a dramatically enlarged occipital/marginal sinus system. On the other hand, hominids in the gracile australopithecine through Homo lineage delivered blood to the vertebral plexus via a widespread network of veins that became more elaborate through time. Mastoid and parietal emissary veins are representatives of this network, and increases in their frequencies during hominid evolution are indicative of its development. Brain size increased with increased frequencies of mastoid and parietal emissary veins in the lineage leading to and including Homo, but remained conservative in the robust australopithecine lineage that lacked the network of veins. The brain is an extremely heatsensitive organ and emissary veins in humans have been shown to cool the brain under conditions of hyperthermia. Thus, the network of veins in the lineage leading to Homo acted as a radiator that released a thermal constraint on brain size. The radiator theory is in keeping with the belief that basal gracile and basal robust australopithecines occupied distinct niches, with the former living in savanna mosaic habitats that were subject to hot temperatures and intense solar radiation during the day.



Hide All

Letters “a” and “r” appearing before authors' initials refer to target article and response respectively.

Abitbol, M. M. (1987) Obstetrics and posture in pelvic anatomy. Journal of Human Evolution 6:243–55. {MMA}
(1989) Variations in blood supply allocations for quadrupedal and for bipedal posture and locomotion. American Journal of Physiological Anthropology 80:239–58. {MMA}
Allee, W. C., & Schmidt, K. (1951) Ecological animal geography. Wiley and Sons. {MCab}
Altman, J. (1987) A quiet revolution in thinking. Nature 328:572–73. {aDF}
Andrews, P. J. (1989) Palaeoecology of Laetoli. Journal of Human Evolution 18:173–81. {WHK}
Ardrey, R. (1976) The hunting hypothesis. Atheneum. {aDF}
Armstrong, E. (1982) Mosaic evolution in the primate brain: Differences and similarities in the Hominid thalamus. In: Primate brain evolution: Methods and concepts, ed. Armstrong, E. & Falk, D.. {GPB}
(1983) Relative brain size and metabolism in mammals. Science 220:1302–04. {rDF, RAB, AW}
Aschoff, J., Gunther, B. & Dramer, K. (1971) Energiehaushalt und Temperaurregulation. Urban & Schwartzenbert. {aDF}
Badeer, H. S. (1985) Elementary principles based on modified Bernoulli’s equation. The Physiologist 28:4146. {aDF}
(1986) Does gravitational pressure of blood hinder flow to the brain of the giraffe? Comparative Biochemistry and Physiology 83:207–11. {aDF}
Baker, M. A. (1979) A brain-cooling system in mammals. Scientific American 240:130–39. {aDF}
(1982) Brain cooling in endotherms in heat and exercise. Annual Review of Physiology 44:8596. {arDF, WHK}
Barnes, J. (1964) The complete works of Aristotle. The revised Oxford translation, vol. 1, 1984. Princeton University Press. {O-JG}
Bashore, T. R., Martinerie, J. M., Weiser, P. C, Greenspon, L. C. & Heffley, E. F. (1988) Preservation of mental processing speed in aerobically fit older men. Psychobiology 25:433–44. {WMB}
Batson, O. V. (1944) Anatomical problems concerned in the study of cerebral blood flow. Federation Proceedings 3:139–44. {aDF}
Bingham, G. P. (1988) Task-specific devices and the perceptual bottleneck. Human Movement Science 7:225–64. {GPB}
Blomquist, C. G., Nixon, J. V., Johnson, R. L. & Mitchell, J. H. (1980) Early cardiovascular adaptation to zero gravity simulated by head-down tilt. Ada Astronautica 7:543–53. {O-JG}
Blumenberg, B. & Lloyd, A. T. (1983) Australopithecus and the origin of the genus Homo: Aspects of biometry and systematics with accompanying catalog of tooth metric data. BioSystems 16:127–67. {rDF}
Blumenschine, R. J. (1986) Carcass consumption sequences and the archaeological distinction of scavenging and hunting. Journal of Human Evolution 15:639–59. {aDF}
(1987) Characteristics of an early hominid scavenging niche. Current Anthropology 28:383407. {aDF, WHK}
Bonnefille, R., Vincens, A. & Buchet, G. (1987) Palynology, stratigraphy and paleoenvironment of a Pliocene hominid site (2.9–3.3 M.Y.) at Hadar, Ethiopia. Palaeogeography, Palaeoclimatology, Palaeoecology 60:249–81. {WHK}
Bortz, W. M. (1985) Physical exercise as an evolutionary force. Journal of Human Evolution 14:145–55. {aDF, WMB}
Bourliere, F. (1985) Primate communities: Their structure and role in tropical ecosystems. International Journal of Primatology 6(1):142. {AZ}
Boyd, G. I. (1930) The emissary foramina of the cranium in man and the anthropoids. Journal of Anatomy 65:108–21. {aDF, GLB, AW}
(1988) The states of human evolution, 3d ed. Prentice-Hall. {CLB}
Brace, C. L. (1979) The stages of human evolution, 2d ed. Prentice-Hall. {CLB}
Brace, C. L. & Montagu, M. F. A. (1965) Mans evolution. Macmillan. {CLB}
Brace, C. L., Smith, S. L. & Hunt, K. D. (in press) What big teeth you had, Grandma! Human tooth size past and present. In: Advances in dental anthropology, ed. Kelley, M. A. & Larsen, C. S., Liss, Alan R.. {CLB}
Brain, C. K. (1958) The Transvaal ape-man-bearing cave deposits. Transvaal Museum Memoir 11. {WHK}
(1988) New information from the Swartkrans cave of relevance to “robust” australopithecines. In: Evolutionary history of the “robust” australopithecines, ed. Grine, F.. Aldine. {aDF}
Braun, J. P. & Tournarde, A. (1977) Venous drainage in the craniocervical region. Neuroradiology 13:155–58. {MCD}
Brengelmann, G. L. (1989) Temperature regulation. In: Scientific foundations of sports medicine, ed. Teitz, C. C. & Decker, B. C.. {GLB}
Breschet, G. (1819) Essai sur les veines du rachis. These Medicale, Paris. {MCD}
Brinnel, H., Boy, J. & Cabanac, M. (1986) Intracranial temperature during passive hyperthermia in humans. Brain Research 363:170–73. {HB}
Brinnel, H. & Cabanac, M. (1989) Tympanic temperature is a core temperature in humans. Journal of Thermal Biology 14:4753. {HB}
Brinnel, H., Cabanac, M. & Caputa, M. (1989) Effect of face cooling on intracranial temperature in hyperthermic and hypothermic humans. In: Abstracts international symposium of thermal physiology (Tromso). {HB}
Brinnel, H., Cabanac, M. & Hales, J. R. S. (1987) Critical upper levels of body temperature, tissue thermosensitivity, and selective cooling in hyperthermia. In: Heat stress: Physical exxertion and environment, ed. Hales, J. R. S. & Richards, D. A. B.. Elsevier Biomedical Division. {aDF}
Brinnel, H., Friedel, J., Caputa, M., Cabanac, M. & Grosshans, E. (1989) Rosacea: Disturbed defense against brain overrheating. Archives of Dermatological Research 281:66–72. {HB}
Brinnel, H., Nagasaka, T. & Cabanac, M. (1987) Enhanced brain protection during passive hyperthermia in humans. European Journal of Applied Physiology 56:540–45. {HB}
Browning, H. (1953) The confluence of dural venous sinuses. American Journal of Anatomy 93:307–29. {arDF, JL}
Burton, A. C. (1972) Physiology and biophysics of the circulation. Year Book Medical Publishers. {aDF}
Butler, H. (1957) The development of certain human dural venous sinuses. Journal of Anatomy 91:510–26. {rDF}
(1967) The development of mammalian dural venous sinuses with especial reference to the postglenoid vein. Journal of Anatomy 102:3356. {rDF}
Byrne, R. W. & Whiten, A. (1988) Machiavellian intelligence. Clarendon Press. {aDF}
Cabanac, M. (1986) Keeping a cool head. News in Physiological Sciences, American Physiological Society 1:4144. {arDF, MCD, PEW}
(1987) Reply to “Comments on keeping a cool head.” News in Physiological Sciences 2:3334. {arDF}
Cabanac, M. & Brinnel, H. (1985) Blood flow in the emissary veins of the human head during hyperthermia. European Journal of Applied Physiology 54:172–76. {arDF, HB, MCap, WHK}
(1988) Beards, baldness, and sweat secretion. European Journal of Applied Physiology 58:3946. {aDF}
Cabanac, M., Brinnel, H. & Mallet, C. (1984) Physiologie humaine: La calvitie est-elle un processus thermoregulateur adaptatif? Comtes Rendus Hebdomadaires des Seances. Academie des Sciencest. 299:499502. {aDF, MCab}
Cabanac, M. & Caputa, M. (1979) Natural selective cooling of the human brain: Evidence of its occurrence and magnitude. Journal of Physiology 286:255–64. {WHK}
Calvin, W. H. (1982) Did throwing stones shape hominid brain evolution? Ethology and Sociobiology 3:115–24. {aDF}
(1983a) A stone’s throw and its launch window: Timing precision and its implications for language and hominid brains. Journal of Theoretical Biology 104:121–35. {aDF}
(1983b) The throwing madonna: Essays on the brain. McGraw-Hill. {aDF}
(1986a) The great encephalization: Throwing juvenilization, developmental slowing, and maternal mortality roles in prehuman brain enlargement. Society for Neuroscience Abstracts 136:9. {aDF}
(1986b) The river that flows uphill: A journey from the big bang to the big brain. Macmillan. {aDF}
Caputa, M. (1981) Selective brain cooling: An important component of thermal physiology. Contributions to Thermal Physiology 32:183–92. {aDF}
Caputa, M. & Cabanac, M. (1988) Precedence of head homoeothermia over trunk homoeothermia in dehydrated men. European Journal of Applied Physiology 57:611–15. {rDF}
Caputa, M. J., Perrin, G. & Cabanac, M.. (1978) Physiologie: Encoulement sanguin reversible dans las veine ophtalmique: Mecanisme de refroidissement selectif du cerveau humain. Comtes Redus Hebdomadaires de Seances. Academie des Sciences. Serie D. (PAMS) 287:1011–14. {aDF, HB}
Caro, C. G., Pedley, T. J., Shroter, R. C. & Seed, W. A. (1978) The mechanisms of circulation. Oxford University Press. {aDF}
Carrier, D. R. (1984) The energetic paradox of human running and hominid evolution. Current Anthropology 25:483–95. {aDF, GPB}
Carroll, R. W. (in press) Feeding ecology and use of termites by lowland gorillas (Gorilla gorilla gorilla) in Dzanga-Sangha Dense Forest Reserve of the Central Africa Republic.Mammalia. {AZ}
Chavaillon, J. (1976) Evidence for the practices of early Pleistocene hominids, Shungura Formation, Lower Omo Valley, Ethiopia. In: Earliest man and environments in the Lake Rudolf Basin, ed. Coppens, Y., Howell, F. C., Issac, G. L. & Leakey, R. E. F.. University of Chicago Press. {BS}
Cheney, D., Seyfarth, R. & Smuts, B. (1986) Social relationships and social cognition in nonhuman primates. Science 234:1361–66. {aDF, RF}
Clarke, G. A. (1988) Some thoughts on the black skull: An archeologist’s assessment of WT-17000 (A. boisei) and systematics in human paleontology. American Anthropologist 90:357–71. {aDF}
Clark, R. J. (1988) A new Australopithecus cranium from Sterkfontein and its bearing on the ancestry of Paranthropus. In: Evolutionary history of the “robust” australopithecines, ed. Grine, F.. Aldine. {aDF}
Clark, S. A., Allard, T., Jenkins, W. M. & Merzenich, M. M. (1988) Receptive fields in the body-surface map in adult cortex defined by temporally correlated inputs. Nature 332:444–45. {aDF}
Clutton-Brock, T. H. & Harvey, P. H. (1980) Primates, brains, and ecology. Journal of Zoology 190:309–23. {RF}
Conroy, G. C. & Vannier, M. W. (1987) Dental development of the Taung skull from computerized tomography. Nature 329:625–27. {rDF}
Conroy, G. C, Vannier, M. W. & Tobias, P. V. (1990) Endocranial features of Australopithecus africanus revealed by 2- and 3-D computed tomography. Science 247: 838–41.
Coppens, Y. (1980) The differences between Australopithecus and Homo: Preliminary conclusions from the Omo Research Expedition’s studies. In: Current argument on early man, ed. Konigsson, L.-K.. Pergamon Press. {BS}
Craigie, E. H. (1938) The comparative anatomy and embryology of the capillary bed of the central nervous system. Research Publications of the Association of Nervous and Mental Diseases 18:328. {MMA}
Crelin, E. (1969) Anatomy of the newborn: An atlas. Lea & Febiger. {rDF}
Darwin, C. (1871) The origin of species and the descent of man. Random House. {aDF}
(1871)The descent of man and selection in relation to sex, 2 vols. Appleton. {CLB, RF}
Das, A. C. & Hasan, M. (1970) The occipital sinus. Journal of Neurosurgery 33:307–11. {aDF}
Dean, M. C. (1988) Another look at the nose and the functional significance of the face and nasal mucous membrane for cooling the brain in fossil hominids. Journal of Human Evolution 17:715–18. {WHK}
Diamond, M. (1967) Extensive cortical depth measurements and neuron sizen the cortex of environmentally enricheid rat. Journal of Comparative Neurology 31:357–64. {WMB}
(1988) Cephalic vascular evolution and development in primates: The stapedial artery and its companion venous sinuses. Ph.D. dissertation. University of Chicago. {rDF}
Dickson, J. A., McKenzie, A. & McLeod, K. (1979) Temperature gradients in pigs during whole-body hyperthermia at 42 degrees C. Journal of Applied Physiology 47:712–17. {GLB}
Dilenge, G. & Perey, B. (1973) An angiographic study of the meningorachidian venous system. Radiology 108:333–37. {aDF, WHK}
Dunbar, R. I. M. (in press) Functional significance of social grooming in primates. Folia primatologica. {RF}
Dustman, R., Ruhling, R., Russel, E., Shearer, D., Bonekat, H., Shiyeoka, J., Wood, J. & Bradford, D. (1984) Aerobic exercise training and improved neuropsychological function of older individuals. Neurobiology of Aging 5:3542. {WMB}
Eckenhoff, J. E. (1970) The physiologic significance of the vertebral venous plexus. Surgery, Gynecology, and Obstetrics 131:7278. {aDF}
Eckhardt, R. (1986) Hominid evolution. Science 234:11. {aDF}
(1987) Hominid brain expansion: Testable hypothesis needed. Current Anthropology 28:206–7. {KRF}
Eisenberg, j. (1981) The mammalian radiations: An analysis of trends in evolution, adapatation, and behaviour. Athlone Press. {RF}
Elgar, M. A. & Harvey, P. H. (1987) Basal metabolic rates in mammals: Allometry, phylogeny, and ecology. Functional ecology 1:25–36. {AW}
Epstein, H. M., Linde, H. W., Crampton, A. R., Ciric, I. S. & Eckenhoff, J. E. (1970) The vertebral venous plexus as a major cerebral venous outflow tract. Anesthesiology 32:332–37. {aDF, WHK}
Falk, D. (1980a) Hominid brain evolution: The approach from paleoneurology. Yearbook of’Physical Anthropology 23:93107. {arDF, RLH}
(1980b) Language, handedness, and primate brains: Did the australopithecines sign? American Anthropologist 82:7278. {aDF}
(1983) Cerebral cortices of East African early hominids. Science 221:1072–74. {arDF}
(1986a) Evolution of cranial blood drainage in hominids: Enlarged occipital/marginal sinuses and emissary foramina. eAmerican Journal of Physical Anthropology 70:311–24. {arDF, WHK, AW}
(1986b) Hominid evolution. Science 234:11. {aDF}
(1987a) Brain lateralization in primates. Yearbook of Physical Anthropology 30:107–25. {aDF}
(1987b) Hominid paleoneurology. Annual Review of Anthropology 16:1330. {aDF}
(1988) Enlarged occipital/marginal sinuses and emissary foramina: Their significance in hominid evolution. In: The evolutionary history of the “robust” australopithecines, ed. Grine, F.. Aldine. {arDF, WHK}
Falk, D. & Conroy, G. (1983) The cranial venous sinus system in Australopithecus afarensis. Nature 306:779–81. {arDF}
Fialkowski, K. R. (1978) Early hominid brain evolution and heat stress: A hypothesis. Studies in Physical Anthropology 4:8792. {aD, WMB, KRF}
(1986) A mechanism for the origin of the human brain: A hypothesis. Current Anthropology 27:288–90. {aDF, KRF}
(1988) Origin of the human brain as a preadaptation to enhanced cognitive powers. Antropologischer Anzeiger 46:317–25. {KRF}
(in press) Origin of the human brain as a reliability adaptation to heat stress: New facts. Current Anthropology. {KRF}
Fleagle, J. G. (1980) Locomotion and posture. In: Malayan forest primates: Ten years’ study in tropical rain forest, ed. Chivers, D. J.. Plenum Press. {BS}
(1988) Primate adaptation and evolution. Academic Press. {AW}
Foldes-Papp, K. (1975) Vom Felshild zum Alphabet. Die Geschichte der Schrift von ihren fruhesten Vorstufen bis zur modernen lateinischen Schreibschrift. Gondrom-Verlag. {O-JG}
Foley, R. (1984) Early man and the Red Queen. Hominid evolution and community ecology, ed. Foley, R.. Academic Press. {RF}
(1987) Hominid species and stone-tool assemblages: How are they related: Antiquity 61:380–92. {aDF}
(1987) Another unique species: Patterns in human evolutionary ecology. Longman. {RF, PEW}
Fox, J. L. (1984) The brain’s dynamic way of keeping in touch. Science 225:820–21. {aDF}
Galaburda, A. M. & Pandya, D. N. (1982) Role of architectonics and connections in the study of primate brain evolution. In: Primate brain evolution: Methods and concepts, ed. Armstrong, E. & Falk, D.. Plenum. {aDF}
Ganong, W. F. (1971) Review of medical physiology. Lange Medical Publications. {aDF}
Gingerich, P. D. (1983) Rates of evolution: Effects of time and temporal scaling. Science 222:159–61. {BHS}
Gius, J. A. & Grier, D. H. (1950) Venous adaptation following bilateral radical neck dissection with excision of the jugular veins. Surgery 28:305–21. {arDF}
Gleadow, A. J. W. (1980) Fission track age of the KBS Tuff and associated hominid remains in northern Kenya. Nature 284:225–30. {CLB}
Godfrey, L. & Jacobs, K. H. (1981) Gradual, autocatalytic and punctuational models of hominid brain evolution: A cautionary tale. Journal of Human Evolution 10:254–72. {aDF}
Goetz, R. H. & Keen, E. N. (1957) Some aspects of the cardiovascular system in the giraffe. Angiology 8:542–64. {aDF}
Goodall, J. (1986) The chimpanzees ofGombe. Harvard University Press. {aDF}
Gould, S. I. & Eldridge, N. (1977) Punctuated equilibria: Tempo and mode of evolution reconsidered. Paleobiology 3:115. {O-JG}
Gould, S. J. (1977a) Bushes and ladders in human evolution. In: ”Ever since Darwin.” Penguin. {RAB}
(1977b) Ontogeny and phylogeny. Harvard University Press. {RAB}
Graf, W. (1959) Patterns of human liver temperature. Ada Physiologica Scandanavica 46:Supplement 160:1135. {GLB}
Gray, H. (1973) Anatomy of the human body (29th ed.). Lea and Febiger. {aDF}
Grine, F. & Kay, R. (1988) Early hominid diets from quantitative image analysis of dental microwear. Nature 333:765–68. {aDF}
Grine, F. E. (1981) Trophic differences between “gracile” and “robust” australopithecines: A scanning electron microscope analysis of occlusal events. South African Journal of Science 77:203–30. {WHK}
Grine, R. E. (1988) Evolutionary history of the “robust” australopithecines: A summary and historical perspective. In: The evolutionary history of the “robust” australopithecines, ed. Grine, F.. Aldine. {rDF}
Griisser, O.-J. (1982) The phylogenetic development of the human brain. Congres Internationale de Paleontologie Humaine. Resumees des Communications 216. {O-JG}
(1988) Die phylogenetische Hirnentwicklung und die funktionelle Lateralisation der menschlichen Grosshirnrinde. In: Psychiatrie des rechten und linken Gehirns, ed. Oepen, G.. Deutscher Arzte-Verlag. {O-JG}
Griisser, O.-J., Griisser-Cornehls, U., Kirchhoff, N. & Kiefer, R. (1985) Averbal social communication of hominids is phylogenetically older than verbal communication. Some evidence from studies in brain lesioned patients. Abstract Taung Diamond Jubilee International Symposium, Johannesburg, South Africa. {O-JG}
Griisser, O.-J. & Weiss, L. R. (1985) Quantitative models on pylogenetic growth of the hominid brain. In: Hominid evolution: Past, present, and future, ed. Tobias, P. V.. Liss, Alan R.. {MMA, O-JG}
Guyton, A. C. (1986) Textbook of medical physiology. W. B. Saunders. {ARH}
Haldane, J. B. S. (1949) Suggestions as to quantitative measurement of rates of evolution. Evolution 3:5156. {BHS}
Hargens, A. R., Millard, R. W., Pettersson, K., Johansen, K. & Meyer, J.-U.
(1987) Gravitational haemodynamics and oedema prevention in the giraffe. Nature 329:5960. {aDF, ARH}
Hartl, D. L. & Clark, A. G. (1989) Principles of population genetics. Sinauer. {rDF}
Harvey, P. H. & Glutton-Brock, T. H. (1985) Life history variation in primates. Evolution 39:559–81. {BHS}
Harvey, P. H., Martin, R. D. & Clutton-Brock, T. H. (1986) Life histories in comparative perspective. In: Primate societies, ed. Smuts, B., Chaney, D. L., Seyfarth, R. M., Wrangham, R. W. & Striraker, T. T.. Chicago University Press. {RF}
Hayward, J. N. & Baker, M. A. (1968) Role of cerebral arterial blood in the regulation of brain temperature in the monkey. American Journal of Physiology 215:389403. {aDF, GLB}
Hewes, G. W. (1973) Primate communication and the gestural origin of language. Current Anthropology 14:524. {aDF}
Hill, K. (1982) Hunting and human evolution. Journal of Human Evolution 11:521–44. {RF}
Hirata, K., Nagasaka, T. & Sugano, Y. (1978) Effect of alternating respiratory pathway on respiratory capacity and tympanic and forehead skin temperatures during exercise. Japanese Journal of Aerospace and Environmental Medicine 15:813. {HB}
Hofman, M. A. (1983) Encephalization in hominids: Evidence for the model of punctuationalism. Brain Behavior and Evolution 22:102–17. {aDF}
(1983) Energy metabolism brain size, and longevity in mammals. Quarterly Review of Biology 58:4955122. {BHS}
(1989) On the evolution and geometry of the brain in mammals. Progress in Neurobiology 32:137–58. {BLF}
Holloway, R. L. (1975) The role of humman social behavior in the evolution of the brain. 43d James Arthur Lecture, 1973. American Museum of Natural History. {aDF, KRF}
(1980) Within-species brain-body weight variability: A re-examination of the Danish data and other primate species. American Journal of Physical Anthropology 53:109–21. {RLH}
(1981a) The endocast of the Omo L338y-6 juvenile hominid: Gracile or robust Australopithecus? American Journal of Physical Anthropology 54:109–18. {aDF, MCD}
(1981b) Revisiting the South African Taung Australopithecine endocast: The position of the lunate sulcus as determined by the steroplotting technique. American Journal of Physical Anthropology 56:4358. {CLB}
(1983) Human paleontological evidence relevant to language behavior. Human Neurobiology 2:105–14. {aDF}
(1983) Human brain evolution: A search for units, Models, and synthesis. Canadian Journal of Anthropology 3(2):215–30. {GPB}
(1988) “Robust” australopithecine brain endocasts: Some preliminary observations. In: The evolutionary history of the “robust” australopithecines, ed. Grine, F.. Aldine. {rDF}
Holloway, R. L. & Post, D. G. (1982) The relativity of relative brain measures. In: Primate brain evolution: Methods and concepts, ed. Armstrong, E. & Falk, D.. Plenum. {aDF}
Humphrey, N. K. (1976) The social function of intellect. In: Growing points in ethology, ed. Bateson, P. P. G. & Hinde, R. A.. Cambridge University Press. {RF}
Ingvar, D. H. & Risberg, J. (1967) Increase of regional cerebral blood flow. Experimental Brain Research 3:195. {MMA}
Isaac, G. LI. (1976) The activities of early African hominids: A review of archaeological evidence from the time span two and a half to one million years ago. In: Human origins, ed. Isaac, G. L. I. & McCown, E. R.. Benjamin. {CLB}
(1978) The food-sharing behavior of protohuman hominids. Scientific American 238:90108. {CLB}
Iwabuchi, T., Sobata, E., Ebina, K., Tsubasisaka, H. & Takiguchi, M. (1986) Dural sinus pressure: Various aspects in human brain surgery in children and adults. American Journal of Physiology 250 (Heart and Circulation Physiology 19):H389-H396. {HB}
Jerison, H. J. (1973) Evolution of the brain and intelligence. Academic Press. {aDF, RF}
(1978) Brain intelligence in whales. In: Whales and whaling. Australian Government Publication Service. {aDF}
(1982a) Allometry brain size, cortical surface, and convolutedness. In: Primate brain evolution: Methods and concepts, ed. Armstrong, E. & Falk., D.Plenum. {aDF}
(1982b) The evolution of biological intelligence. In: Handbook of human intelligence, ed. Sternberg, R. J.. Cambridge University Press. {HJJ}
(1983) The evolution of the mammalian brain as an information processing system. In: Advances in the study of mammalian behavior, ed. Eisenberg, J. F. & Kleimann, D. G.. American Society of Mammalogists Special Publication 7. {KRF}
(1985) Animal intelligence as encephalization. Philosophical Transactions of the Royal Society (London), 6308:2135. {HJJ}
Johanson, D. C, Lovejoy, C. O., Kimbel, W. H., White, T. D., Ward, S. C, Bush, M. E., Latimer, B. M. & Coppens, Y. (1982) Morphology of the Pliocene partial hominid skeleton (A.L. 288–1) from the Hadar formation, Ethiopia. American Journal of Physical Anthropology 57:403–51. {rDF}
Johanson, D. C. & White, T. D. (1979) A systematic assesment of early African hominids. Science 203:321–30. {CLB}
Johanson, D. C, White, T. D. & Coppens, Y. (1978) A new species of the genus Australopithecus (Primates: Hominidae) from the Pliocene of eastern Africa. Kirtlandia 28:114. {CLB, BS}
Johnson, J. I., Switzer, R. C. & Kirsch, J. A. W. (1982) Phylogeny through brain traits: The distribution of categorizing characters in contemporary mammals. Brain, Behavior, Evolution 20:97117. {HJJ}
Kaas, J. H. (1988) Development of cortical sensory maps. In: Neurobiology of neocortex, ed. Rakic, P. & Singer, W.. John Wiley & Sons. {aDF}
Kalaria, R. N., & Harik, S. I. (1987) Blood brain barrier monamine oxidase. Journal of Neurochemistry 49:856–64. {WMB}
Kay, R. F. & Grine, R. E. (1988) Tooth morphology, wear, and diet in Australopithecus and Paranthropus from Southern Africa. In: The evolutionary history of the “robust” australopithecines, ed. Grine, F.. Aldine. {rDF}
Kety, S. (1960) The cerebral circulation. In: Handbook of physiology-neurophysiology 3:1751—60, ed. Feld, John. American Physiologic Society, Washington, D.C. {WMB}
Kimbel, W. H. (1984) Variation in the pattern of cranial venous sinuses and hominid phylogeny. American Journal of Physical Anthropology 63:243–63. {arDF, MCD, WHK, JL, BS}
Kleiber, M. (1932) Body size and metabolism. Hilgardia 6:315–53. {BHS}
Kleinerman, J. & Sancette, S. M. (1955) Effect of mild steady-state exercise on cerebral and general hemodynamics of normal untrained subjects. Journal of Clinical Investigation 34:985. {WMB}
Krantz, G. S. (1968) Brain size and hunting ability in earliest man. Current Anthropology 9:450–51. {aDF, WMB}
Kruska, D. (1988) Mammalian domestication and its effect on brain structure and behavior. In: Intelligence and evolutionary biology, ed. Jerison, H. J. & Jerison, I.. Springer-Verlag. {HJJ}
Laitman, J. T. & Reidenberg, J. S. (1988) Advances in understanding the relationship between the skull base and larynx with comments on the origin of speech. Human Evolution 3:99109. {KRF}
Lande, R. (1979) Quantitative genetic analysis of multivariate evolution, applied to brain: Body size allometry. Evolution 33:402–16. {HJJ}
Leakey, M. D. (1979) Footprints in the ashes of time. National Geographic 155:446–57. {CLB}
(1984) Disclosing the past. Doubleday. {CLB}
Leakey, M. D. & Hay, R. L. (1979) Pliocene footprints in the Laetolil beds at Laetoli, northern Tanzania. Nature 278:317–23. {aDF, CLB}
Lee, P. C. (in press) Comparative ethological approaches in modelling hominid behaviour. Ossa 14. {RF}
Le Gros Clark, W. E. (1970) History of the primates. British Museum (Natural History). {AW}
Lemons, D. E., Chien, S., Crawshaw, L. I., Weinbaum, S. & Jiji, L. M. (1987) Significance of vessel size and type in vascular heat transfer. American Journal of Physiology 253:R128R135. {GIB}
Lillywhite, H. B. (1987a) Circulatory adaptations of snakes to gravity. American Zoologist 27:8195. {aDF}
(1987b) Snakes under pressure. Natural History, November:5967. {aDF}
Linder, H. (1948) Biologie. Metzler-Verlag. {O-JG}
Lovejoy, C O. (1975) Biomechanical perspectives on the lower limb of early hominids. In: Primate functional morphology and evolution, ed. Tuttle, R. H.. Mouton. {BHS}
(1981) The origin of man. Science 211:341–50. {RF, PEW}
Macphail, E. M. (1982) Brain and intelligence in vertebrates. Clarendon Press. {RAB}
Marshack, A. (1985) Hierarchical evolution of the human capacity: The Paleolithic evidence. 54th James Arthur Lecture, 1984. American Museum of Natural History. {aDF}
Martin, R. D. (1981) Relative brain size and metabolic rate in terrestrial vertebrates. Nature 293:5760. {RAB, RF, AW}
(1983) Human brain evolution in an ecological context. James Arthur Lecture on the Evolution of the Human Brain. American Museum of Natural History. {CLB, BHS}
Matsushima, T., Rhoton, A. L., de’Oliveira, E. & Peace, D. (1983) Microsurgical anatomy of the veins of the posterior fossa. Journal of Neurosurgery 59:63105. {MCD}
Mayr, E. (1970) Population, species, and evolution. Harvard University Press. {KRF}
McDougall, I., Maier, R., Sutherland-Hawkes, P. & Gleadow, A. J. W. (1980) K-Ar age estimate for the KBS Tuff, East Turkana, Kenya. Nature 284:230–34. {CLB}
McNab, B. K. & Eisenberg, J. F. (1989) Brain size and its relation to the rate of metabolism in mammals. American Naturalist 133:157–67. {AW}
Mettler, F. A. (1955) Culture and the structural evolution of the neural system. James Arthur Lecture on the Evolution of the Human Brain. American Museum of Natural History. {BHS}
Milton, K. (1988) Foraging behaviour and the evolution of primate intelligence. In: Machiavellian intelligence: Social expertise and the evolution of intellect in monkeys, apes, and humans, ed. Byrne, R. W. & Whiten, A.. Clarendon Press. {AW}
Milvy, P. (1977) The marathon: Physiological, medical, epidemiological, and psychological studies. Annals of the New York Academy of Science 301. {GLB}
Mitchell, D., Labum, H. P., Nijland, M. J. M., Zurovsky, Y. & Mitchell, G. (1987) Selective brain cooling and survival. South African Journal of Science 83:598604. {PEW}
Nadel, E. R. (1987) Comments on “Keeping a cool head.” News in Physiological Sciences 2:33. {aDF}
Nagasaka, T., Brinnel, H., Hirata, K., Noda, Y. & Sugimoto, N. (1989) Increase in venous flow through ophtalmic veins enhances selective brain cooling in hyperthermic humans. In: Proceeding of the International Symposium of Thermal Physiology Trornso. {HB}
Narebski, J. (1985) Human brain homeothermy during sleep and wakefulness: An experimental and comparative approach. Ada Neurobiologiae Experimental. 45:6375. {MCap}
Neilsen, K. C. & Owman, C. (1967) Adrenergic innervation of pial arteries related to the circle of Willis in the cat brain. Research 6:773–76. {WMB}
Newman, R. W. (1970) Why man is such a sweaty and thirsty naked animal: A speculative review. Human Biology 42:1227. {aDF}
Ojemann, G. A. (1983) Brain organization for language from the perspective of electrical stimulation mapping. Behavioral and Brain Sciences 6:189230. {aDF}
Olivier, G. (1972) Capacite cranienne, langage articule et definition du genre Homo. Comtes Rendus Hebdomadaires des Seances de le Academie des Sciences. Series D. Sciences Naturelles 274:1469–72. {aDF}
Olson, T. R. (1981) Basicranial morphology of the extant hominoids and Pliocene hominids: The new material from the Hadar formation, Ethiopia, and its significance in early human evolution and taxonomy. In: Aspects of human evolution, ed. Stringer, C. B.. Taylor & Francis. {arDF}
Padget, D. H. (1956) The cranial venous system in man in reference to development, adult configuration and relations to arteries. American Journal of Anatomy 98:307–55. {rDF}
(1957) The development of the cranial venous system in man, from the viewpoint of comparative anatomy. Contributions to Embryology 36:79140. {aDF, WHK}
Pagel, M. D. & Harvey, P. H. (1988) How mammals produce large-brained offspring. Evolution 42:948–57. {AW}
(1989) Taxonomic differences in the scaling of brain on body weight among mammals. Science 244:1589–93. {CLB}
Passingham, R. E. (1973) Anatomical differences between the cortex of man and other primates. Brain, Behavior, Evolution 7:337–59. {RLH}
(1975a) Changes in the size and organization of the brain in man and his ancestors. Brain, Behavior, Evolution 11:7390. {RLH}
(1975b) The brain and intelligence. Brain Behavior and Evolution 11:115. {aDF}
Pedley, T. J. (1987) How giraffes prevent oedema. Nature 329:1314. {aDF}
Penfield, W. & Rasmussen, T. (1950) The cerebral cortex of man: A clinical study of localization of function. Macmillan. {aDF}
Pilbeam, D. (1980) Major trends in human evolution. In: Current argument on early man, ed. Konigsson, L. K.. Pergamon. {CLB}
Platon (1968) Timaios. In: Sdmtliche Werke, vol. 3, 6th ed., ed. E. Loewenthal. {O-JG}
Plotkin, H. C. (1988) Behavior and evolution. In: The role of behavior in evolution, ed. Plotkin, H. C.. MIT Press. {GPB}
Pritchard, J. A., MacDonald, P. C. & Gant, N. F. (1985) Williams obstetrics (16th ed.). Appleton-Century-Crofts. {MMA}
Radinsky, L. B. (1978) Evolution of brain size in carnivores and ungulates. American Naturalist 112:815–31. {aDF, RLH}
(1979) The fossil record of primate brain evolution. 49th James Arthur Lecture. American Museum of Natural History. {aDF}
Raichle, M. E. (1987) Circulatory and metabolic correlates of brain functions in normal humans. In: Handbook of physiology: The nervous system V. American Physiologic Society. {WMB}
Rak, Y. & Howell, F. C. (1978) Cranium of a juvenile Australopithecus boisei from the lower Omo basin, Ethiopia. American Journal of Physical Anthropology 48:345–66. {rDF}
Rakic, P. (1988) Specification of cerebral cortical areas. Science 241:170–76. {aDF}
Richards, G. (1986) Freed hands or enslaved feet? A note on the behavioural implications of ground-dwelling bipedalism. Journal of Human Evolution 15:143–50. {aDF}
(1989) Human behavioural evolution: A physiomorphic model. Current Anthropology 30:244–55. {aDF}
Robinson, J. T. (1963) Adaptive radiation in the australopithecines and the origin of man. In: African ecology and human evolution, ed. Howell, F. C. & Bourliere, F.. Aldine. {aDF}
Rockel, A. J., Hioms, R. W. & Powell, T. P. S. (1980) The basic uniformity in structure of the neocortex. Brain 103:221–44. {HJJ}
Rowell, L. B. (1986) Human circulation during physical stress. Oxford University Press. {GLB}
Sacher, G. A. (1959) Relation of lifespan to brain weight and body weight in mammals. In: The lifespan of animals, Ciba Foundation Colloquia on Aging, vol. 5, ed. Wolstenholme, G. E. W. & O’Connor, M.. Churchill. {BHS}
(1978) Longevity aging, and death:An evolutionary perspective. Gerontologist 18:112–19. {BHS}
Sacher, G. A. & Staffeldt, E. (1974) Relation of gestation time to brain weight for placental mammals: Implications for the theory of vertebrate growth. American Naturalist 108:593616. {BHS}
Sarieh, V. (1971) A molecular approach to the question of human origins. In: Background for man, ed. Sarieh, V. & Dolhinow, P.. Little, Brown. {aDF}
Scharrer, E. (1960) Brain function and the evolution of cerebral vascularisation. James Arthur Lecture on the evolution of the human brain. American Museum of Natural History. {MMA}
Scheibel, A. B., Paul, L. A., Fried, I., Forsythe, A. B., Tomiyasu, U., Wechsler, A., Kao, A. & Slotnick, J. (1985) Dendritic organization of the anterior speech area. Experimental Neurology 87:109–17. {HJJ}
Scheinberg, P. (1975) Cerebral blood flow. In: The nervous system, ed. Tower, D. B.. Raven Press. {MMA}
Scheinberg, P., Blackburn, L. I., Rich, M. & Saslow, M. (1954) Effect of physical exercise on cerebral circulation and metabolism. American Journal of Medicine 16:549–54. {WMB}
Schmidt, R. F. & Thews, H., eds. (1989) tiuman physiology, 2d ed. Springer Press. {O-JG}
Schmidt-Nielsen, K. (1979) Animal physiology: Adaptation and environment. Cambridge University Press. {aDF}
(1983) Animal physiology: Adaptation and environment. Cambridge University Press. {MCap}
Senut, B. & Tardieu, C. (1985) Functional aspects of Plio-Pleistocene hominid limb bones: Implications for taxonomy and phylogeny. In: Ancestors: The hard evidence, ed. Delson, E.. Liss, Alan R.. {rDF}
Seymour, R. S. & Johansen, K. (1987) Blood flow uphill and downhill: Does a siphon facilitate circulation above the heart? Comparative Biochemistry & & Physiology 88A: 167–70. {ARH}
Shenkin, H. A., Harmel, M. H. & Kety, S. S. (1948) Dynamic anatomy of the cerebral circulation. Archives of Neurology and Psychiatry 60:240–52. {MCD}
Shipman, P. (1983) Early hominid lifestyle: Hunting and gathering or foraging and scavenging. In: Animals and archaeology. 1. Hunters and their prey, ed. Clutton-Brock, J. & Grigson, C.. BAR International Series 163. {CLB}
(1986) Scavenging or hunting in early hominids: Theoretical framework and tests. American Anthropologist 88:2743. {CLB}
Shipman, P. & Harris, J. M. (1988) Habitat preference and paleoecology of Australopithecus boisei in Eastern Africa. In: Evolutionary history of the “robust” australopithecines, ed. Grine, F.. Aldine. {aDF, WHK}
Shiraki, K., Sagawa, S., Tajima, F., Yokota, A., Hashimoto, M. & Brengelmann, G. L. (1988) Independence of brain and tympanic temperatures in an unanesthetized human. Journal of Applied Physiology 65:482–86. {arDF, GLB}
Shiu, P. C, Hanafee, W. N., Wilson, G. H. & Rand, R. W. (1968) Cavernous sinus venography. American Journal of Roentgenology, Radium Therapy and Nuclear Medicine 104:5762. {MCD}
Sminia, P., Van der Zee, J., Wondergem, J. & Haveman, J. (1990) A review on the effect of hyperthermia on the central nervous system. Progress in Hyperthermia. {HB}
Smith, B. H. (1989) Dental development as a measure of life history in primates. Evolution 43:683–87. {BHS}
Stern, J. T. & Susman, R. L. (1983) The locomotor anatomy of Australopithecus afarensis. American Journal of Physical Anthropology 60:279317. {aDF}
Stryer, L. (1981) Biochemistry, 2d ed. Freeman Press. {O-JG}
Susman, R. L. (1988) Hand of Paranthropus robustus from Member 1, Swartkrans: Fossil evidence for tool behavior. Science 240:781–84. {aDF, BS}
Taylor, C. R. (1974) Exercise and thermoregulation. In: Environmental Physiology. International Review of Science, Physiology Series I, ed. Robertshaw, D.. Butterworths. {aDF}
Thornton, W. E. & Ord, J. (1977) Physiological mass measurements in Skylab. In: Biomedical results from Skylab, ed. Johnston, R. S. & Dietlein, L. F.. NASA SP-377, Washington, D.C. {O-JG}
Tobias, P. V. (1967) The cranium and maxillary dentition of Australopithecus (Zinjanthropus) boisei. Olduvai Gorge, vol. 2. Cambridge University Press. {arDF, BS}
(1968) The pattern of venous sinus grooves in the robust australopithecines and other fossil and modern hominoids. In: Anthropologie und Humangenetik, ed. Peter, R., Schwartzfischer, F., Glowatzki, G. & Ziegelmayer, G.. Gustav Fischer. {arDF}
(1971) The brain in hominid evolution. Columbia University Press. {aDF}
(1973) Implications of the new age estimates of the early South African hominids. Nature 246:7983. {rDF}
(1981) The emergence of man in Africa and beyond. Philosophical Transactions of the Royal Society of London, Series B 292:4356. {aDF}
(1987) The brain of Homo habilis: A new level of organization in cerebral evolution. Journal of Human Evolution 16:741–61. {aDF}
Tobias, P. V. & Falk, D. (1988) Evidence for a dual pattern of cranial venous sinuses on the endocranial cast of Taung (Australopithecus africanus). American Journal of Physical Anthropology 76:309–12. {arDF, WHK}
Toth, N. (1985) Archeological evidence for preferential right-handedness in the lower and middle Pleistocene, and its possible implications. Journal of Human Evolution 14:607–14. {aDF}
(1987) The first technology. Scientific American 256:112–21. {CLB}
Trevathan, W. R. (1987) Human birth: An evolutionary perspective. Aldine de Gruyter. {BLF}
Tutin, C. E. G. & Fernandez, M. (1985) Foods consumed by sympatric populations of Gorilla gorilla gorilla and Pan troglodytes troglodytes. International Journal of Primatology 6(1):2743. {AZ}
Tuttle, R. H. (1985) Ape footprints and Laetoli impressions: A response to the SUNY claims. In: Hominid evolution: Past, present and future, ed. Tobias, P. V.. Liss, Alan R.. {arDF}
(1987) Kinesiological inferences and evolutionary implications from Laetoli bipedal trails G-l, G-2/3, and A. In: Laetoli, a Pliocene site in northern Tanzania, ed. Leakey, M. D. & Harris, J. M.. Clarendon Press. {arDF}
(1988) What’s new in African paleoanthropology? Annual Review of Anthropology 17:391426. {aDF, WHK}
Van Citters, R. L., Kemper, W. S. & Franklin, D. L. (1968) Blood flow and pressure in the giraffe carotid artery. Comparative Biochemistry 6-Physiology 24:1035–42. {ARH}
Van Valen, L. (1974) Brain size and intelligence in man. American Journal of Physical Anthropology 40:417–24. {aDF, RLH}
Vidal, P. P., Graf, W. & Berthoz, A. (1986) The orientation of the cervical vertebral column in unrestrained awake animals. I. Resting position. Experimental Brain Research 61:549–59. {O-JG}
von Neumann, J. (1963) Probabilistic logic and the synthesis of reliable organisms from unreliable components. Collected works, vol. 5. Pergamon Press. {KEF}
Vrba, E. S. (1988) Late Pliocene climatic events and hominid evolution. In: The evolutionary history of the “robust” australopithecines, ed. Grine, F.. Aldine. {rDF, WHK}
Walker, A., Leakey, R. E., Harris, J. M. & Brown, F. H. (1986) 2.5-Myr Australopithecus boisei from west of Lake Turkana, Kenya. Nature 322:517–22. {arDF}
Washburn, S. L. (1960) Tools and human evolution. Scientific American 203:6375. {aDF, CLB}
(1982) Human evolution. Perspectives in Biology and Medicine 25:583602. {aDF}
Washburn, S. L. & Lancaster, C. S. (1968) The evolution of hunting. In: Man the hunter, ed. Lee, R. B. & DeVore, I.. Aldine. {RF}
Weinstein, J. D. & Hedges, T. R. (1962) Studies of intracranial and orbital vasculature of the rhesus monkey (Macaca mulatto). Anatomical Record 144:3741. {WHK}
Wheeler, P. E. (1984) The evolution of bipedality and loss of functional body hair in hominids. Journal of Human Evolution 13:9198. {aDF, PEW}
(1985) The loss of functional body hair in man: The influence of thermal environment, body form, and bipedality. Journal of Human Evolution 14:2328. {aDF, PEW}
(1988) Stand tall and stay cool. New Scientist 12 May:6265. {aDF, RAB, PEW}
Whitby, J. D. & Dunkin, L. J. (1971) Cerebral oesophageal and nasopharyngeal temperatures. British Journal of Anesthesiology 43:673–76. {GLB}
White, E. L. (1989) Cortical circuits: Synaptic organization of the cerebral cortex: Structure, function and theory. Birkhauser. {HJJ}
White, T. D. (1988) The comparative biology of “robust” Australopithecus: Australopithecines, ed. Grine, F. E.. Aldine de Gruyter. {WHK}
Whiten, A. & Byrne, R. W. (1987) Taking (Machiavellian) intelligence apart. In: Machiavellian intelligence, ed. Byrne, R. W. & Whiten, A.. Oxford University Press. {RAB}
(1988) The Machiavellian intelligence hypotheses. In: Machiavellian intelligence: Social expertise and the evolution of intellect in monkeys, apes, and humans, ed. Byrne, R. W. & Whiten, A.. Clarendon Press. {AW}
Woodhall, B. (1936) Variations of the cranial venous sinuses in the region of the Torcular Herophili. Archives of Surgery 33:297314. {rDF}
(1939) Anatomy of the cranial blood sinuses with particular reference to the lateral. Laryngoscope 49:9661010. {JL}
Woolsey, C. N. (1958) Organization of somatic sensory and motor areas of the cerebral cortex. In: Biological and biochemical bases of behavior, ed. Harlow, H. & Woolsey, C.. University of Wisconsin Press. {aDF}
(1964) Cortical localization as defined by evoked potential and electrical stimulation studies. In: Cerebral localization and organization, ed. Schaltenbrand, G. & Woolsey, C. N.. University of Wisconsin Press. {aDF}
Wrangham, R. W. (1977) Feeding behaviour of chimanzees in Gombe National Park, Tanzania. In: Primate ecology: Studies of feeding and ranging behaviour in lemurs, monkeys, and apes, ed. Clutton-Brock, T. H.. Academic Press. {AW}
Zihlman, A. (1985) Australopithecus afarensis: Two sexes or two species? In: Hominid evolution: Past, present and future, ed. Tobias, P. V.. Liss, Alan R.. {rDF}
Zihlman, A. L. & Cohn, B. A. (1986) Responses of hominid skin to the savanna. Suid-Afrikaanse Tydskrif vir Wetenskap 82:8990. {aDF}
(1988) The adaptivee response of human skin to the savanna. Human Evolution 3:397409. {aDF}
Zouaoui, A. & Hidden, G. (1989) The cervical vertebral venous plexus, a drainage route for the brain. Surgical and Radiological Anatomy 11:7981. {MCD}
Zwiebel, W. J. (1982) Introduction to vascular ultrasonography. Grune & Stratton. {MMA}



Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed