International Journal of Primatology

, Volume 31, Issue 2, pp 275–299 | Cite as

Subchondral Bone Apparent Density and Locomotor Behavior in Extant Primates and Subfossil Lemurs Hadropithecus and Pachylemur

  • John D. Polk
  • Scott A. Williams
  • Jeffrey V. Peterson
  • Charles C. Roseman
  • Laurie R. Godfrey


We analyze patterns of subchondral bone apparent density in the distal femur of extant primates to reconstruct differences in knee posture, discriminate among extant species with different locomotor preferences, and investigate the knee postures used by subfossil lemur species Hadropithecus stenognathus and Pachylemur insignis. We obtained computed tomographic scans for 164 femora belonging to 39 primate species. We grouped species by locomotor preference into knuckle-walking, arboreal quadruped, terrestrial quadruped, quadrupedal leaper, suspensory and vertical clinging, and leaping categories. We reconstructed knee posture using an experimentally validated procedure of determining the anterior extent of the region of maximal subchondral bone apparent density on a median slice through the medial femoral condyle. We compared subchondral apparent density magnitudes between subfossil and extant specimens to ensure that fossils did not display substantial mineralization or degradation. Subfossil and extant specimens were found to have similar magnitudes of subchondral apparent density, thereby permitting comparisons of the density patterns. We observed significant differences in the position of maximum subchondral apparent density between leaping and nonleaping extant primates, with leaping primates appearing to use much more flexed knee postures than nonleaping species. The anterior placement of the regions of maximum subchondral bone apparent density in the subfossil specimens of Hadropithecus and Pachylemur suggests that both species differed from leaping primates and included in their broad range of knee postures rather extended postures. For Hadropithecus, this result is consistent with other evidence for terrestrial locomotion. Pachylemur, reconstructed on the basis of other evidence as a committed arboreal quadruped, likely employed extended knee postures in other activities such as hindlimb suspension, in addition to occasional terrestrial locomotion.


apparent density locomotion posture subchondral bone subfossil lemur 



We thank Profs. E. Hirasaki, Y. Hamada, and T. C. Rae for their invitation to participate in the Primate Functional Morphology Symposium in August 2008. We also thank Judy Chupasko and her staff at Harvard’s Museum of Comparative Zoology for their generous loan of extant primate specimens for CT scanning. We thank Dr. Armand Rasoamiaramanana and the late Dr. Gisèle Randria (formerly Ravololonarivo) for the specimen (Pachylemur) loaned from the University of Antananarivo and for the paleontological research accord under which the Hadropithecus specimen was found. Kevin Reynolds and his staff at Mount Auburn Hospital provided excellent assistance in CT scanning. Jennifer Swartz assisted with preliminary analyses of the patterns of subchondral density. Rebecca Stumpf provided excellent advice at all stages of the project. This research was supported by grants from the National Science Foundation: BCS 0639630, with REU supplement (J. D. Polk), and BCS 0129185 (D. Burney, W. Jungers, and L. R. Godfrey), and the University of Illinois, Urbana-Champaign (J. D. Polk). We also thank the editors, Bill Jungers, and 1 anonymous reviewer for their substantial improvements to the manuscript.


  1. Ahluwalia, K. (2000). Knee joint load as determined by tibial subchondral bone density: Its relationship to gross morphology and locomotor behavior in catarrhines [PhD]. Stony Brook, NY: Stony Brook University, 315 pp.Google Scholar
  2. Alexander, R. M. (1985). The maximum forces exerted by animals. Journal of Experimental Biology, 115, 231–238.PubMedGoogle Scholar
  3. Biewener, A. A. (1989). Scaling body support in mammals: Limb posture and muscle mechanics. Science, 245, 45–48.CrossRefPubMedGoogle Scholar
  4. Biewener, A. A. (1990). Biomechanics of mammalian terrestrial locomotion. Science, 250, 1097–1103.CrossRefPubMedGoogle Scholar
  5. Burgess, N. D., D’Amico Hales, J., Underwood, E. C., Dinerstein, E., Olson, D., Itoua, I., et al. (2004). Terrestrial ecoregions of Africa and Madagascar: A conservation assessment. Washington, DC: Island Press.Google Scholar
  6. Burney, D. A., Burney, L. P., Godfrey, L. R., Jungers, W. L., Goodman, S. M., Wright, H. T., et al. (2004). A chronology for late prehistoric Madagascar. Journal of Human Evolution, 47, 25–63.CrossRefPubMedGoogle Scholar
  7. Burney, D. A., Vasey, N., Godfrey, L. R., Ramilisonina, Jungers, W. L., Ramarolahy, M., et al. (2008). New findings at Andrahomana Cave, Southeastern Madagascar. Journal of Cave and Karst Studies, 70(1), 13–24.Google Scholar
  8. Carlson, K. J., & Patel, B. A. (2006). Habitual use of the primate fore-limb is reflected in the material properties of subchondral bone in the distal radius. Journal of Anatomy, 208, 659–670.CrossRefPubMedGoogle Scholar
  9. Carter, D. R., & Beaupre, G. S. (2001). Skeletal form and function: Mechanobiology of skeletal development, aging and regeneration. Cambridge, UK: Cambridge University Press.Google Scholar
  10. Carter, D. R., & Hayes, W. C. (1977). The compressive behavior of bone as a two phase porous structure. Journal of Bone and Joint Surgery, 59A, 954–962.Google Scholar
  11. Catlett, K. K., Schwartz, G. T., Godfrey, L. R., & Jungers, W. L. (2010). “Life History Space”: A multivariate analysis of life history variation in extant and extinct Malagasy lemurs. American Journal of Physical Anthropology. doi: 10.1002/ajpa.21236.
  12. Cohen, J. (1990). Things I have learned (so far). American Psychologist, 45, 1304–1312.CrossRefGoogle Scholar
  13. Crowley, B. E., Godfrey, L. R., & Irwin, M. T. (2010). A glance to the past: Subfossils, stable isotopes, seed dispersal, and lemur species loss in southern Madagascar. American Journal of Primatology, 71, 1–13.Google Scholar
  14. Currey, J. D. (1988). The effect of porosity and mineral content on the Young’s modulus of elasticity of compact bone. Journal of Biomechanics, 21, 131–139.CrossRefPubMedGoogle Scholar
  15. Currey, J. D. (2002). Bones: Structure and mechanics. Princeton, NJ: Princeton University Press.Google Scholar
  16. Decary, R. (1926). Une mission scientifique dans le S.E. de Madagascar. Bull. de l’Académie Malgache, 9, 79–86.Google Scholar
  17. Demes, B., & Günther, M. M. (1989). Biomechanics and allometric scaling in primate locomotion and morphology. Folia Primatologica, 53318, 125–141.CrossRefGoogle Scholar
  18. Demes, B., & Carlson, K. J. (2009). Locomotor variation and bending regimes of capuchin limb bones. American Journal of Physical Anthropology, 139, 558–571.CrossRefPubMedGoogle Scholar
  19. Demes, B., Larson, S. G., Stern, J. T., Jungers, W. L., Biknevicius, A. R., & Schmitt, D. (1994). The kinematics of primate quadrupedalism: “Hindlimb drive” reconsidered. Journal of Human Evolution, 26, 353–374.CrossRefGoogle Scholar
  20. Demes, B., Fleagle, J. G., & Jungers, W. L. (1999). Takeoff and landing forces of leaping strepsirhine primates. Journal of Human Evolution, 37, 279–292.CrossRefPubMedGoogle Scholar
  21. Eckstein, F., Müller-Gerbl, M., Steinlechner, M., Kierse, R., & Putz, R. (1995). Subchondral bone density in the human elbow assessed by computed tomography osteoabsorptiometry: A reflection of the loading history of the joint surfaces. Journal of Orthopedic Research, 13, 268–278.CrossRefGoogle Scholar
  22. Eckstein, F., Merz, B., Schon, M., Jacobs, C. R., & Putz, R. (1999). Tension and bending, but not compression alone, determine the functional adaptation of subchondral bone in incongruous joints. Anatomy and Embryology, 199(1), 85–97.CrossRefPubMedGoogle Scholar
  23. Fedigan, L, & Fedigan, L. M. (1988). Cercopithecus aethiops: a review of field studies. In A. Gautier-Hion, R. Fouliere, J-P. Gautier, & J. Kingdon (Eds.), A primate radiation: Evolutionary biology of the African guenons. Cambridge, UK: Cambridge University Press.Google Scholar
  24. Felsenstein, J. (1985). Phylogenies and the comparative method. American Naturalist, 125, 1–15.CrossRefGoogle Scholar
  25. Fischer, K. J., Jacobs, C. R., & Carter, D. R. (1995). Computation method for determination of bone and joint loads using bone density distributions. Journal of Biomechanics, 28, 1127–1135.CrossRefPubMedGoogle Scholar
  26. Fleagle, J. G. (1976). Locomotor behavior and skeletal anatomy of sympatric Malaysian leaf monkeys (Presbytis obscura and Presbytis melalophos). Yearbook of Physical Anthropology, 20, 440–453.Google Scholar
  27. Fleagle, J. G. (1980). Locomotion and posture. In D. J. Chivers (Ed.), Malayan Forest primates (191–207). New York: Plenum Press.Google Scholar
  28. Fleagle, J. G. (1999). Primate adaptation and evolution. New York: Academic Press.Google Scholar
  29. Godfrey, L. R. (1988). Adaptive diversification of Malagasy strepsirrhines. Journal of Human Evolution, 17, 93–134.CrossRefGoogle Scholar
  30. Godfrey, L. R., & Jungers, W. L. (2002). Quaternary fossil lemurs. In W. C. Hartwig (Ed.), The primate fossil record (pp. 97–121). Cambridge, UK: Cambridge University Press.Google Scholar
  31. Godfrey, L. R., Jungers, W. L., Wunderlich, R. E., & Richmond, B. G. (1997). Reappraisal of the postcranium of Hadropithecus (Primates, Indroidea). American Journal of Physical Anthropology, 103, 529–556.CrossRefPubMedGoogle Scholar
  32. Godfrey, L. R., Semprebon, G. M., Jungers, W. L., Sutherland, M. R., Simons, E. L., & Solounias, N. (2004). Dental use wear in extinct lemurs: Evidence of diet and niche differentiation. Journal of Human Evolution, 47, 145–169.CrossRefPubMedGoogle Scholar
  33. Godfrey, L. R., Jungers, W. L., Burney, D. A., Vasey, N., Ramilisonina, Wheeler, W., et al. (2006a). New discoveries of skeletal elements of Hadropithecus stenognathus from Andrahomana Cave, southeastern Madagascar. Journal of Human Evolution, 51(4), 395–410.CrossRefGoogle Scholar
  34. Godfrey, L. R., Jungers, W. L., & Schwartz, G. T. (2006b). Ecology and extinction of Madagascar’s subfossil lemurs. In L. Gould & M. Sauther (Eds.), Lemurs: Ecology and adaptation (pp. 41–64). New York: Springer.Google Scholar
  35. Godfrey, L. R., Jungers, W. L., Schwartz, G. T., & Irwin, M. T. (2008a). Ghosts and orphans: Madagascar’s vanishing ecosystems. In J. G. Fleagle & C. C. Gilbert (Eds.), Elwyn Simons: A search for origins (pp. 361–395). New York: Springer.Google Scholar
  36. Godfrey, L. R., Crowley, B. E., Muldoon, K. M., King, S. J., & Burney, D. A. (2008b). The Hadropithecus conundrum. American Journal of Physical Anthropology (Supplement), 46, 105.Google Scholar
  37. Grandidier, G. (1905). Recherches sur les lémuriens disparus et en particulier sur ceux qui vivaient à Madagascar. Nouvelles Archives du Muséum, 7, 1–142, plus 12 plates.Google Scholar
  38. Hanna, J. B., Polk, J. D., & Schmitt, D. (2006). Forelimb and hindlimb forces in walking and galloping primates. American Journal of Physical Anthropology, 130(4), 529–535.CrossRefPubMedGoogle Scholar
  39. Harvey, P. H., & Pagel, M. D. (1991). The comparative method in evolutionary biology. Oxford: Oxford University Press.Google Scholar
  40. Horvath, J. E., Weisrock, D. W., Embry, S. L., Fiorentino, I., Balhoff, J. P., Kappeler, P., et al. (2008). Development and application of a phylogenomic toolkit: Resolving the evolutionary history of Madagascar’s lemurs. Genome Research, 18, 489–499.CrossRefPubMedGoogle Scholar
  41. Hoshino, A., & Wallace, W. A. (1987). Impact-absorbing properties of the human knee. Journal of Bone and Joint Surgery, 69B, 807–811.Google Scholar
  42. Housworth, E. A., Martins, E. P., & Lynch, M. (2004). The phylogenetic mixed model. American Naturalist, 163, 84–96.CrossRefPubMedGoogle Scholar
  43. Jouffroy, F. K. (1960). Caractères adaptatifs dans les proportions des members chez les Lémurs fossiles. Comptes Rendus de l’Académie des Sciences Paris, 251, 2756–2757.Google Scholar
  44. Jungers, W. L. (1988). Relative joint size and hominoid locomotor adaptations with implications for the evolution of hominid bipedalism. Journal of Human Evolution, 17, 247–265.CrossRefGoogle Scholar
  45. Jungers, W. L. (1991). Scaling of postcranial joint size in hominoid primates. Human Evolution, 6, 391–399.CrossRefGoogle Scholar
  46. Jungers, W. L., Falsetti, A. B., & Wall, C. E. (1995). Shape, relative size, and size-adjustments in morphometrics. Yearbook of Physical Anthropology, 1995, 137–161.CrossRefGoogle Scholar
  47. Jungers, W. L., Demes, B., & Godfrey, L. R. (2008). How big were the ‘giant’ extinct lemurs of Madagascar? In J. G. Fleagle & C. C. Gilbert (Eds.), Elwyn Simons: A search for origins (pp. 343–360). New York: Springer.Google Scholar
  48. Lemelin, P., Hamrick, M. W., Richmond, B. G., Godfrey, L. R., Jungers, W. L., & Burney, D. A. (2008). New hand bones of Hadropithecus stenognathus: Implications for the paleobiology of the Archaeolemuridae. Journal of Human Evolution, 54, 405–413.CrossRefPubMedGoogle Scholar
  49. Lovejoy, C. O. (2007). The natural history of human gait: Part 3. The knee. Gait & Posture, 25, 325–341.CrossRefGoogle Scholar
  50. Lynch, M. (1991). Methods for the analysis of comparative data in evolutionary biology. Evolution, 45, 1065–1080.CrossRefGoogle Scholar
  51. McHenry, H. M. (1988). New estimates of body weight in early hominids and their significance to encephalization and megadontia in “robust” Australopithecines. In F. E. Grine (Ed.), Evolutionary history of the “robust” Australopithecines (pp. 133–148). New York: Aldine de Gruyter.Google Scholar
  52. McHenry, H. M., & Berger, L. R. (1998). Body proportions in Australopithecus afarensis and A. africanus and the origin of the genus Homo. Journal of Human Evolution, 35(1), 1–22.CrossRefPubMedGoogle Scholar
  53. Muldoon, K. M., Godfrey, L. R., & Jungers, W. L. (2009). Geographic patterning in subfossil primate community dynamics in Madagascar. American Journal of Physical Anthropology (Supplement), 48, 195.Google Scholar
  54. Müller-Gerbl, M., Putz, R., Hodapp, N., Schulte, E., & Wimmer, B. (1989). Computed tomography-osteoabsorptiometry for assessing the density distribution of subchondral bone as a measure of long-term mechanical adaptation in individual joints. Skeletal Radiology, 18(7), 507–512.CrossRefPubMedGoogle Scholar
  55. Müller-Gerbl, M., Putz, R., Hodapp, N., Schulte, E., & Wimmer, B. (1990). Computed-tomography osteoabsorptiometry – A method of assessing the mechanical condition of the major joints in a living subject. Clinical Biomechanics, 5(4), 193–198.CrossRefGoogle Scholar
  56. Muller-Gerbl, M., Putz, R., & Kenn, R. (1992). Demonstration of subchondral bone-density patterns by 3-dimensional Ct osteoabsorptiometry as a noninvasive method for in vivo assessment of individual long-term stresses in joints. Journal of Bone and Mineral Research, 7, S411–S418.Google Scholar
  57. O’Neill, M. C., & Dobson, S. D. (2008). The degree and pattern of phylogenetic signal in primate long-bone structure. Journal of Human Evolution, 54, 309–322.CrossRefPubMedGoogle Scholar
  58. Orlando, L., Calvignac, S., Schnebelen, C., Douady, C. J., Godfrey, L. R., & Hänni, C. (2008). DNA from extinct giant lemurs links archaeolemurids to extant indriids. BMC Evolutionary Biology, 8, Article no. 121.Google Scholar
  59. Paradis, E. (2006). Analysis of phylogenetics and evolution with R. New York; Springer.Google Scholar
  60. Patel, B. A., & Carlson, K. J. (2006). Hand postures reflect bone apparent density patterns in the primate distal radius. American Journal of Physical Anthropology, 144–145.Google Scholar
  61. Patel, B. A., & Carlson, K. J. (2007). Bone density spatial patterns in the distal radius reflect habitual hand postures adopted by quadrupedal primates. Journal of Human Evolution, 52, 130–141.CrossRefPubMedGoogle Scholar
  62. Patel, B. A., & Carlson, K. J. (2008). Apparent density patterns in subchondral bone of the sloth and anteater forelimb. Biology Letters, 4(5), 486–489.CrossRefPubMedGoogle Scholar
  63. Polk, J. D. (2002). Adaptive and phylogenetic influences on musculoskeletal design in cercopithecine primates. Journal of Experimental Biology, 205(21), 3399–3412.PubMedGoogle Scholar
  64. Polk, J. D. (2004). The influence of body size and limb proportions on joint posture in terrestrial monkeys and fossil hominins. Journal of Human Evolution, 47, 237–252.CrossRefPubMedGoogle Scholar
  65. Polk, J. D., Blumenfeld, J., & Ahluwalia, K. (2008). Knee posture predicted from subchondral apparent density in the distal femur: An experimental validation. Anatomical Record, 291, 293–302.CrossRefGoogle Scholar
  66. Polk, J. D., Williams, S. A., & Peterson, J. V. (2009). Body size and joint posture in Primates. American Journal of Physical Anthropology, 140, 359–375.CrossRefPubMedGoogle Scholar
  67. Radin, E. L., & Paul, I. L. (1971). The importance of bone in sparing articular cartilage from impact. Clinical Orthopaedics and Related Research, 78, 342–344.CrossRefPubMedGoogle Scholar
  68. Radin, E. L., Paul, I. L., & Lowy, M. (1970). A comparison of the dynamic force transmitting properties of subchondral bone and articular cartilage. Journal of Bone and Joint Surgery, 52A, 444–456.Google Scholar
  69. Ravololonarivo, G. F. N. (1990). Contribution à l’étude de la colonne vertébrale du genre Pachylemur (Lamberton, 1946): Anatomie et analyse cladistique. 3 rd Cycle thesis, University of Antananarivo, Madagascar.Google Scholar
  70. Reynolds, T. R. (1985). Mechanics of increased support of weight by the hindlimb in primates. American Journal of Physical Anthropology, 67, 335–349.CrossRefPubMedGoogle Scholar
  71. Rice, J. C., Cowin, S. C., & Bowman, J. A. (1988). On the dependency of the elasticity and strength of cancellous bone on apparent density. Journal of Biomechanics, 21, 155–168.CrossRefPubMedGoogle Scholar
  72. Rohlf, F. J. (2006). Tpsdig2: Scholar
  73. Ruff, C. (1987). Structural allometry of the femur and tibia in Hominoidea and Macaca. Folia Primatologica, 48, 9–49.CrossRefGoogle Scholar
  74. Ruff, C. (1988). Hindlimb articular surface allometry in Hominoidea and Macaca, with comparisons to diaphyseal scaling. Journal of Human Evolution, 17(7), 687–714.CrossRefGoogle Scholar
  75. Ruff, C. B., & Leo, F. P. (1986). Use of computed tomography in skeletal structure research. Yearbook of Physical Anthropology, 29, 181–196.CrossRefGoogle Scholar
  76. Ryan, T. M., Burney, D. A., Godfrey, L. R., Göhlich, U., Jungers, W. L., Vasey, N., et al. (2008). A reconstruction of the Vienna skull of Hadropithecus stenognathus. Proceedings of the National Academy of Sciences of the United States of America, 105(31), 10698–10701.CrossRefGoogle Scholar
  77. Samii, V. F., Les, C. M., Schulz, K. S., Keyak, J. H., & Stover, S. M. (2002). Computed tomographic osteoabsorptiometry of the elbow joint in clinically normal dogs. American Journal of Veterinary Research, 63, 1159–1166.CrossRefPubMedGoogle Scholar
  78. Schmitt, D. (1994). Forelimb mechanics as a function of substrate type during quadrupedalism in two anthropoid primates. Journal of Human Evolution, 26, 441–457.CrossRefGoogle Scholar
  79. Schmitt, D. (1999). Compliant walking in Primates. Journal of Zoology (London), 248, 149–160.CrossRefGoogle Scholar
  80. Shapiro, L. J., Seiffert, C. V. M., Godfrey, L. R., Jungers, W. L., Simons, E. L., & Randria, G. F. N. (2005). Morphometric analysis of lumbar vertebrae in extinct Malagasy strepsirrhines. American Journal of Physical Anthropology, 128(4), 823–839.CrossRefPubMedGoogle Scholar
  81. Shapiro, S. S., & Wilk, M. B. (1965). An analysis of variance test for normality (complete samples). Biometrika, 52(3/4), 591–611.CrossRefGoogle Scholar
  82. Simon, S. R., Rose, R. M., Radin, E. L., & Paul, I. L. (1972). Response of joints to impact loading 2. In-vivo behavior of subchondral bone. Journal of Biomechanics, 5(3), 267–272.Google Scholar
  83. Smith, R. J., & Cheverud, J. M. (2002). Scaling of sexual dimorphism in body mass: A phylogenetic analysis of Rensch’s rule in Primates. International Journal of Primatology, 23, 1095–1135.CrossRefGoogle Scholar
  84. Sokal, R. R., & Rohlf, F. J. (1995). Biometry (3rd ed.). New York: W. H. Freeman.Google Scholar
  85. Tardieu, C., & Jouffroy, F. K. (1979). Les surfaces articulaires fémorales du genou chez les Primates: étude préliminaire. Annales des Sciences Naturelles Zoologie (Paris), 13, 23–38.Google Scholar
  86. Taylor, W. R., Ehrig, R. M., Heller, M. O., Schell, H., Seebeck, P., & Duda, G. N. (2006). Tibio-femoral joint contact forces in sheep. Journal of Biomechanics, 39(5), 791–798.CrossRefPubMedGoogle Scholar
  87. von Eisenhart, R., Adam, C., Steinlechner, M., Muller-Gerbl, M., & Eckstein, F. (1999). Quantitative determination of joint incongruity and pressure distribution during simulated gait and cartilage thickness in the human hip joint. Journal of Orthopaedic Research, 17(4), 532–539.CrossRefGoogle Scholar
  88. Walker, A. C. (1974). Locomotor adaptations in past and present prosimian primates. In F. A. Jenkins Jr. (Ed.), Primate locomotion (pp. 349–381). New York: Academic Press.Google Scholar
  89. Walker, A. (1983). Prosimian locomotor behavior. In G. A. Doyle & R. D. Martin (Eds.), The study of prosiman behavior (pp. 543–566). New York: Academic Press.Google Scholar
  90. Walker, A., Ryan, T. M., Silcox, M. T., Simons, E. L., & Spoor, F. (2008). The semicircular canal system and locomotion: The case of extinct lemuroids and lorisoids. Evolutionary Anthropology, 17(3), 135–145.CrossRefGoogle Scholar
  91. Wall, J. C., Chatterji, S. K., & Jeffery, J. W. (1979). Age-related changes in the density and tensile strength of human femoral cortical bone. Calcified Tissue International, 27, 105–108.CrossRefPubMedGoogle Scholar
  92. Wiley, D. F., Amenta, N., Alcantara, D. A., Ghosh, D., Kil, Y. J., Delson, E., Harcourt-Smith, W., Rohlf, F. J., St. John, K., & Hamann, B. (2005). Evolutionary morphing. Proceedings IEEE Visualization, 2005, 431–438.Google Scholar
  93. Wright, T. M., & Hayes, W. C. (1977). Fracture mechanics parameters for compact bone – effects of density and specimen thickness. Journal of Biomechanics, 10, 419–430.CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • John D. Polk
    • 1
  • Scott A. Williams
    • 1
  • Jeffrey V. Peterson
    • 2
  • Charles C. Roseman
    • 1
  • Laurie R. Godfrey
    • 3
  1. 1.Department of AnthropologyUniversity of Illinois Urbana-ChampaignUrbanaUSA
  2. 2.Department of AnthropologySan Diego State UniversitySan DiegoUSA
  3. 3.Department of AnthropologyUniversity of MassachusettsAmherstUSA

Personalised recommendations