Skip to main content
SpringerLink
Log in

Paleoclimatic Variation and Brain Expansion during Human Evolution

  • Published:
Human Nature Aims and scope Submit manuscript

Abstract

One of the major adaptations during the evolution of Homo sapiens was an increase in brain size. Here we present evidence that a significant and substantial proportion of variation in brain size may be related to changes in temperature. Based on a sample of 109 fossilized hominid skulls, we found that cranial capacities were highly correlated with paleoclimatic changes in temperature, as indexed by oxygen isotope data and sea-surface temperature. Indeed, as much as 52% of the variance in the cranial capacity of these skulls could be accounted for by temperature variation at 100 ka intervals. As an index of more short-term seasonal fluctuations in temperature, we examined the latitude of the sites from which the crania originated. More than 22% of the variance in cranial capacity of these skulls could be accounted for by variation in equatorial distance.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4

Similar content being viewed by others

References

  • Ash, J. A., & Gallup, G. G. Jr. (2007). Brain size, intelligence, and paleoclimatic variation. In G. Gehr & G. Miller (Eds.), Mating intelligence: Sex, relationships, and the mind’s reproductive system. Mahwah, NJ: Lawerence Erlbaum Associates.

    Google Scholar 

  • Aiello, L. C., & Wood, B. A. (1994). Cranial variables as predictors of hominine body mass. American Journal of Physical Anthropology, 95, 409–426.

    Article  Google Scholar 

  • Andreasen, N. C., Flaum, M., Swayze II, V., O’Leary, D. S., Alliger, R., Cohen, G., et al. (1993). Intelligence and brain structure in normal individuals. American Journal of Psychiatry, 150, 130–134.

    Google Scholar 

  • Barton, R. A., & Harvey, P. H. (2000). Mosaic evolution of brain structure in mammals. Nature, 405, 1055–1058.

    Article  Google Scholar 

  • Beals, K. L., Smith, C. L., & Dodd, S. M. (1984). Brain size, cranial morphology, climate and time machines. Current Anthropology, 25, 301–330.

    Article  Google Scholar 

  • Bischoff, J. L., & Shamp, D. D. (2003). The sima de los huesos hominids date to beyond U/Th equilibrium (>350 kyr) and perhaps to 400–500 kyr: New radiometric dates. Journal of Archaeological Science, 30, 275–280.

    Article  Google Scholar 

  • Blackburn, T. M., Gaston, K. J., & Loder, N. (1999). Geographic gradients in body size: A clarification on Bergmann’s rule. Diversity and Distributions, 5, 165–174.

    Article  Google Scholar 

  • Bradley, R. S. (1999). Paleoclimatology: Reconstructing climates of the quaternary (2nd ed.). San Diego: Academic.

    Google Scholar 

  • Bruner, E., & Manzi, G. (2005). CT-based description and phyletic evaluation of the archaic human calvarium from ceprano, Italy. Anatomical Record, 285A, 643–658.

    Article  Google Scholar 

  • Calvin, W. H. (1996). How brains think. New York: Basic Books.

    Google Scholar 

  • Cohen, J., Cohen, P., West, S. G., & Aiken, L. S. (2003). Applied multiple regression/correlation analysis for the behavioral sciences (3rd ed.). Mahwah, NJ: Lawrence Erlbaum Associates.

    Google Scholar 

  • Conroy, H. C., Weber, H., Seidler, H., Recheis, W., zur Nedden, D., & Mariam, J. H. (2000). Endocranial capacity of the Bodo cranium determined from three-dimensional computed tomography. American Journal of Physical Anthropology, 113, 111–118.

    Article  Google Scholar 

  • Crowley, T. J., & North, G. R. (1991). Paleoclimatology. New York: Oxford University Press.

    Google Scholar 

  • deMenocal, P. B., & Bloemendal, J. (1995). Plio-Pleistocene subtropical African climate variability and the paleoenvironment of hominid evolution: A combined data-model approach. In E. Vrba, G. Denton, L. Burckle, & T. Partridge (Eds.), Paleoclimate and evolution, with emphasis on human origins (pp. 262–288). New Haven: Yale University Press.

    Google Scholar 

  • De Miguel, C., & Henneberg, M. (2001). Variation in hominid brain size: How much is due to method? Homo, 52, 2–56.

    Google Scholar 

  • Dunbar, R. (1998). The social brain hypothesis. Evolutionary Anthropology, 6, 178–191.

    Article  Google Scholar 

  • Egan, V., Chiswick, A., Santosh, C., Naidu, K., Rimmington, J. E., & Best, J. J. K. (1994). Size isn’t everything: A study of brain volume, intelligence and auditory evoked potentials. Personality and Individual Differences, 17, 357–367.

    Article  Google Scholar 

  • Egan, V., Wickett, J. C., & Vernon, P. A. (1995). Brain size and intelligence: Erratum, addendum, and correction. Personality and Individual Differences, 19, 113–115.

    Article  Google Scholar 

  • Falk, D. (1990). Brain evolution in Homo—the radiator theory. Behavioral and Brain Sciences, 13, 333–343.

    Google Scholar 

  • Falk, D., & Gage, T. B. (1997). Flushing the radiator? A reply to braga and boesch. Journal of Human Evolution, 33, 495–502.

    Article  Google Scholar 

  • Gignac, G. E., Vernon, P. A., & Wickett, J. C. (2003). Factors influencing the relationship between brain size and intelligence. In H. Nyborg (Ed.), The scientific study of general intelligence: Tribute to Arthur R. Jensen (pp. 93–106). Oxford: Pergamon.

    Google Scholar 

  • Harvey, I., Persaud, R., Ron, M. A., Baker, G., & Murray, R. M. (1994). Volumetric MRI measurements in bipolars compared with schizophrenics and healthy controls. Psychological Medicine, 24, 689–699.

    Article  Google Scholar 

  • Hershkovitz, I., Greenwald, C., Rothschild, B. M., Latimer, B., Dutour, O., Jellema, L. M., et al. (1999). The elusive diploic veins: Anthropological and anatomical perspective. American Journal of Physical Anthropology, 108, 345–358.

    Article  Google Scholar 

  • Holloway, R. L., Broadfield, D. C., & Yuan, M. S. (Eds.) (2004). The human fossil record: Brain endocasts—the paleoneurological evidence. New York: Wiley.

    Google Scholar 

  • Kareken, D. A., Gur, R. C., Mozley, P. D., Mozley, L. H., Saykin, A. J., Shtasel, D. L., et al. (1995). Cognitive functioning and neuroanatomic volume measures in schizophrenia. Neuropsychology, 9, 211–219.

    Article  Google Scholar 

  • Klein, R. (1999). The human career: Human biological and cultural origins (2nd ed.) Chicago: University of Chicago Press.

    Google Scholar 

  • Kunman, K., Inbar, M., & Clark, R. J. (1999). Palaeoenvironments and cultural sequence of the florisbad middle stone age hominid site, South Africa. Journal of Archaeological Science, 26, 1409–1425.

    Article  Google Scholar 

  • Larick, R., Ciochon, R. L., Zaim, Y., Suminto, S., Rizal, Y., Aziz, F., et al. (2001). Early Pleistocene 40Ar/39Ar ages for bapang formation hominins, Central Jawa, Indonesia. Proceedings of the National Academy of Sciences, 98, 4866–4871.

    Article  Google Scholar 

  • Lee, S-H. (2005). Brief communication: Is variation in the cranial capacity of the Dmansi sample too high to be from a single species? American Journal of Physical Anthropology, 127, 263–266.

    Article  Google Scholar 

  • Lee, S-H., & Wolpoff, M. H. (2003). The pattern of evolution in Pleistocene human brain size. Paleobiology, 29, 186–196.

    Article  Google Scholar 

  • McDougall, I., Brown, F. H., & Fleagle, J. G. (2005). Stratigraphic placement of modern humans from Kibish, Ethiopia. Nature, 433, 733–735.

    Article  Google Scholar 

  • Marlow, J. R., Lange, C. B., Wefer, G., & Rosell-Melé, A. (2000). Upwelling intensification as part of the Pliocene–Pleistocene climate transition. Science, 290, 2288–2291.

    Google Scholar 

  • Posthuma, D., De Geus, E. J. C., Baare, W. F. C., Pol, H. E. H., Kahn, R. S., & Boomsma, D. I. (2002). The association between brain volume and intelligence is of genetic origin. Nature Neuroscience, 5, 83–84.

    Article  Google Scholar 

  • Potts, R. (1998a). Environmental hypotheses of hominin evolution. Yearbook of Physical Anthropology, 41, 93–136.

    Article  Google Scholar 

  • Potts, R. (1998b). Variability selection in hominid evolution. Evolutionary Anthropology, 7, 81–96.

    Article  Google Scholar 

  • Potts, R. (2001). Complexity and adaptability in human evolution. In F. Ayala, C. P. Simon, & B. Wood (Eds.), Development of the human species and its adaptation to the environment (pp. 1–31). Retrieved August 10, 2005 from http://www.uchicago.edu/aff/mwc-amacad/biocomplexity/conference_papers/PottsComplexity.pdf.

  • Raz, N., Torres, I. J., Spencer, W. D., Millman, D., Baertschi, J. C., & Sarpel, G. (1993). Neuroanatomical correlates of age-sensitive and age-invariant cognitive abilities: An in vivo MRI investigation. Intelligence, 17, 407–422.

    Article  Google Scholar 

  • Reiss, A. L., Abrams, M. T., Singer, H. S., Ross, J. L., & Denckla, M. B. (1996). Brain development, gender and IQ in children. A volumetric imaging study. Brain, 119, 1763–1774.

    Article  Google Scholar 

  • Rightmire, G. P. (2004). Brain size and encephalization en early to mid-Pleistocene homo. American Journal of Physical Anthropology, 124, 109–123.

    Article  Google Scholar 

  • Rushton, J. P., & Jensen, A. R. (2005). Thirty years of research on race differences in cognitive ability. Psychology, Public Policy, and Law, 11, 235–294.

    Article  Google Scholar 

  • Shackelton, N. J. (1995). New data on the evolution of Pliocene climate variability. In E. Vrba, G. H. Denton, T. C. Partridge, & L. H. Burckle (Eds.), Paleoclimate and evolution, with emphasis on human origins (pp. 242–248). New Haven: Yale University Press.

    Google Scholar 

  • Shackelton, N. J., Berger, A., & Peltier, W. R. (1990). An alternative astronomical calibration of the lower Pleistocene timescale based on ODP site 677. Transactions of the Royal Society of Edinburgh, Earth Science, 81, 251–261.

    Google Scholar 

  • Shackelton, N. J., Hall, M. A., & Pate, D. (1995). Pliocene stable isotope stratigraphy of site 846. In N. G. Pisias, L. A. Janacek, A. Palmer-Julson, & T. H. Van Andel (Eds.), Proceedings of the ocean drilling program, scientific results (vol. 138, pp. 337–355). College Station, TX: Ocean Drilling Program.

    Google Scholar 

  • Shen, G., Cheng, H., & Edwards, R. L. (2004). Mass spectrometric U-series dating of New Cave at Zhoukoudian, China. Journal of Anthropological Science, 31, 337–342.

    Google Scholar 

  • Tobias, P. V. (1991). Olduvai Gorge, vol. 4: The skulls, endocasts and teeth of Homo Habilis. Cambridge: Cambridge University Press.

    Google Scholar 

  • Wickett, J. C., & Vernon, P. A. (1994). Peripheral nerve conduction velocity, reaction time, and intelligence: An attempt to replicate Vernon and Mori (1992). Intelligence, 18, 127–131.

    Article  Google Scholar 

  • Wickett, J. C., Vernon, P. A., & Lee, D. H. (2000). Relationships between factors of intelligence and brain volume. Personality and Individual Differences, 29, 1095–1122.

    Article  Google Scholar 

  • Willerman, L., Schultz, R., Rutledge, J. N., & Bigler, E. D. (1991). In vivo brain size and intelligence. Intelligence, 15, 223–228.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Psychology, University at Albany, State University of New York, 1400 Washington Ave., Albany, NY, 12222, USA

    Jessica Ash & Gordon G. Gallup Jr.

Authors
  1. Jessica Ash
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Gordon G. Gallup Jr.
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Gordon G. Gallup Jr..

Appendix

Appendix

Fossil information

Number

Fossil

Taxon†

Capacity (cc)

Date (Ma)

1

SK 47 (adult)

Early h

595.000a

1.900a

2

Stw 53

Early h

570.000a

1.900a

3

SK 847

h, hh/he

507.000a

1.900a

4

SK 27

h

475.000a

1.900a

5

KNM-ER 1470 (Koobi Fora)

hher

776.000a

1.890a

6

KNM-ER 3732 (Koobi Fora)

hher

622.500a

1.890a

7

KNM-ER 1813 (Koobi Fora)

hh

506.333a

1.890a

8

Omo L894-1

h

500.000a

1.890a

9

Dmansi 2280

hh

775.000b

1.860b

10

Dmansi 2282

hh

650.000b

1.860b

11

Dmansi 2700

hh

600.000c

1.860b

12

KNM-ER 1590 (Koobi Fora)

hr

782.500a

1.850a

13

KNM-ER 1805 (Koobi Fora)

hh

616.000a

1.850a

14

Modjokerto (adult)

he

855.000a

1.800a

15

OH 24 (Olduvai)

hh

597.000d

1.800a

16

KNM-ER 3733 (Koobi Fora)

hher

825.400a

1.780a

17

OH 7 (adult) (Olduvai)

hh

674.000a

1.780a

18

OH 16 (adult) (Olduvai)

hh

639.200a

1.670a

19

Sangiran 4

he

856.000a

1.660a

20

OH 13 (adult) (Olduvai)

hh

662.286a

1.660a

21

Sangiran 31

he

1,000.000a

1.660a

22

KNM-WT 15000 (adult) (Nariokotome)

he

904.500a

1.600a

23

KNM-ER 3883 (Koobi Fora)

hher

825.667a

1.570a

24

Sangiran 12

he

951.000a

1.25

25

Sangiran 3 (adult)

he

900.000a

1.25

26

Sangiran 10

he

868.600a

1.25

27

Sangiran 9

he

856.000a

1.25

28

Sangiran 2

he

792.571a

1.25

29

Sangiran 17

he

1,020.000a

1.25

30

OH 9 (Olduvai)

he

1,070.500a

1.200a

31

Gongwangling 1

he

779.000a

1.150a

32

Buia

he

800.000a

1.000a

33

Trinil 2

he

940.000a

0.900a

34

Ceprano

hhei

1,185.000a

0.850k

35

OH 12 (Olduvai)

he

732.330a

0.840a

36

Ternifine

ahs

1,300.000a

0.750a

37

Bodo

hhei

1,250.000f

0.600f

38

Nanjing

he

1,000.000c

0.600c

39

Atapuerca 4 (AT 600)

hant

1,390.000a

0.500g

40

Atapuerca 6 (11- to 14-year-old)

hant

1,153.333a

0.500g

41

Atapuerca 5 (AT 700)

hant

1,125.000a

0.500g

42

Sambungmacan 1

he

1,056.333a

0.500a

43

Salé 1

he

911.000a

0.400a

44

Araho 21

hhei

1,138.667a

0.400a

45

Broken hill 1 (Kabwe)

hhei

1,310.000a

0.350a

46

Saldanha 1 (Elandsfontein)

hhei

1,216.667a

0.350a

47

Yunxian

he

1,100.000a

0.350a

48

Ndutu 1

ahs

1,100.000a

0.350a

49

Petralona 1

hhei

1,266.556a

0.325a

50

Reilingn

hhei

1,432.000a

0.300a

51

Swanscombe 1

hhei

1,305.000a

0.300a

52

Narmada 1

he

1,249.333a

0.300a

53

Steinheim 1

hhei

1,111.192a

0.300a

54

Florisbad 1

ahs

1,280.000a

0.279h

55

KNM-ER 3884

ahs

1,400.000a

0.270a

56

Ngawi

he

1,000.000c

0.250c

57

Hexian

he

1,012.500a

0.250a

58

Zhoukoudian (III)

he

937.500a

0.210i

59

Zhoukoudian (VI)

he

850.000a

0.210i

60

Zhoukoudian L1 (X)

he

1,225.000a

0.210i

61

Zhoukoudian h3 (V)

he

1,220.000a

0.210i

62

Zhoukoudian D1 (II)

he

1,030.000a

0.210i

63

Zhoukoudian L3 (XII)

he

1,030.000a

0.210i

64

Zhoukoudian L2 (XI)

he

1,015.000a

0.210i

65

Dali 1

ahs

1,160.000a

0.205a

66

Ehrinhsdorf 9

hhei

1,450.000a

0.203a

67

Sambungmacan 3

he

900.000a

0.200a

68

Solo 5, Ngandong V

he

1,266.167a

0.200a

69

Solo 9, Ngandong IX

he

1,135.000a

0.200a

70

Solo 1, Ngandong I

he

1,121.429a

0.200a

71

Solo 6, Ngandong VI

he

1,115.714a

0.200a

72

Solo 10, Ngandong X

he

1,109.000a

0.200a

73

Omo 2

ahs

1,432.500a

0.195j

74

Jinniushan

he

1,316.667a

0.187a

75

Vértesszöllös 2

ahs

1,334.571a

0.186a

76

Biache

hhei

1,200.000a

0.178a

77

Fontéchevade 2

hn

1,420.000a

0.160a

78

La Chaise

hn

1,065.000a

0.151a

79

Singa 1

hn

1,550.000a

0.150a

80

KNM-ES-11693 (Eliye Springs)

ahs

1,375.000a

0.150a

81

Jebel Irhoud 2

hn

1,400.000l

0.140a

82

Jebel Irhoud 1

hn

1,305.000l

0.140a

83

Krapina-D

hn

1,450.000a

0.130a

84

Krapina 3

hn

1,200.000a

0.130a

85

Ngaloba

ahs

1,283.500a

0.125a

86

Daka (BOU VP-2/66)

he

995.000c

0.100c

87

Saccopastore 2

hn

1,295.000a

0.100a

88

Tabun C1

hn

1,270.500a

0.100a

89

Saccopastore 1

hn

1,234.333a

0.100a

90

Skhul 9

hn

1,587.333a

0.090a

91

Skhul 4

hn

1,554.500a

0.090a

92

Skhul 5

hn

1,499.500a

0.090a

93

Skhul 2

hn

1,300.000a

0.090a

94

La Ferrassie 1

hn

1,650.200a

0.068a

95

Teshik-Tash (adult)

hn

1,581.000a

0.060a

96

Gibraltar 1 (Forbes’ Quarry)

hn

1,226.750a

0.060a

97

Monte Circeo I

hn

1,551.000a

0.055a

98

Amud 1

hn

1,745.000a

0.051a

99

Shanidar 1

hn

1,650.000a

0.050a

100

La Chapelle-aux-Saints

hn

1,626.000a

0.050a

101

Shanidar 5

hn

1,550.000a

0.050a

102

Spy 2

hn

1,487.400a

0.050a

103

Spy 1

hn

1,457.500a

0.050a

104

La Quina 5

hn

1,345.250a

0.050a

105

Neandertal 1

hn

1,337.750a

0.050a

106

Ganovce 1

hn

1,320.000a

0.050a

107

Le Moustier 1

hn

1,486.200a

0.040a

108

Galilee

ahs

1,400.000a

0.040a

109

Eyasi

ahs

1,235.000a

0.035a

  1. †Legend for taxa:
  2. ahs: Archaic Homo sapiens
  3. h: Homo
  4. hant: Homo antecessor
  5. he: Homo erectus
  6. hher: Homo ergaster
  7. hh: Homo habilis
  8. hhei: Homo heidelbergensis
  9. hn: Neandertal
  10.  
  11. References:
  12. aDe Miguel and Henneberg (2001)
  13. bLee (2005)
  14. cLee and Wolpoff (2003)
  15. dTobias (1991)
  16. eLarick et al. (2001)
  17. fConroy et al. (2000)
  18. gBischoff and Shamp (2003)
  19. hKunman et al. (1999)
  20. iShen et al. (2004)
  21. jMcDougall et al. (2005)
  22. kBruner and Manzi (2005)
  23. lHolloway et al. (2004)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Ash, J., Gallup, G.G. Paleoclimatic Variation and Brain Expansion during Human Evolution. Hum Nat 18, 109–124 (2007). https://doi.org/10.1007/s12110-007-9015-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12110-007-9015-z

Keywords

Search

Navigation