Key publications
Cashmore LA, Zakrzewski SR (2013). Assessment of musculoskeletal stress marker development in the hand.
International Journal of Osteoarchaeology,
23(3), 334-347.
Abstract:
Assessment of musculoskeletal stress marker development in the hand
The analysis of musculoskeletal stress marker (MSM) development is a commonly employed tool in osteological surveys and is used to infer patterns of occupational activity and societal organisation in archaeological populations. Although the majority of research into upper limb MSMs has focused on the bones of the arm, the bones of the hand have been conspicuous by their absence. This is likely to be due to methodological issues surrounding the study of hand bones and a presumed lack of variation in MSM development in this area. To date, there have been no systematic studies investigating the presence and variation in MSM morphology for the muscles of the human hand. To address this issue, a presence/absence scoring system was developed for twelve sites of muscle origin and insertion in the metacarpals and phalanges, which was used to determine bilateral asymmetry in the hands of 31 individuals from the Naval Hospital Cemetery site in Greenwich, London. Analysis found observable variation in MSM development between and within the hands, which could be used to determine patterns of asymmetry within the sample. Comparisons with MSM scores from the humeri of these individuals indicate a differentiation in MSM development and asymmetry between these anatomical regions. Levels of asymmetry in the hands and humeri were generally low, with only the dorsal interossei displaying statistically significant asymmetry. Subsequent upper limb MSM research will benefit from the inclusion of data from the hands. These results do not support the continued use of the humerus as a proxy for MSM expression across the upper limb as a whole and suggest that important information regarding behavioural asymmetry in the hands is being lost because of the continual exclusion of this anatomical unit from MSM research. © 2011 John Wiley & Sons, Ltd.
Abstract.
Cashmore L (2009). Can hominin 'handedness' be accurately assessed?.
Ann Hum Biol,
36(5), 624-641.
Abstract:
Can hominin 'handedness' be accurately assessed?
The expression of a strong, population-level right hand preference has, to date only been unequivocally identified in Homo sapiens and is often considered to be unique to this species. For this reason, and because of purported co-evolutionary links between this trait and language capabilities in modern humans, the identification of hand preference in the hominin fossil record has long been of interest to researchers studying the evolution of 'handedness' within the genus Homo. Identifying hand preference in skeletal samples, however, is not straightforward. Problems arise from difficulties in determining the precise nature of the relationship between hand use and bone morphology, the methods by which hand preference is assessed, the paucity of material available for study, and even what is meant by the term 'handedness'. Various attempts have been made to address these issues, encompassing a range of methodological approaches, such as comparisons of osteological techniques, studies of prehistoric material culture and ethnographic analysis of hand use behaviours in modern hunter-gatherer societies and non-human primate groups. What such research suggests is that hand preference is a complex phenomenon, in both extant and extinct groups, and in order to assess its expression in extinct populations care must be paid to the questions asked of the available material and the methodologies used to answer them.
Abstract.
Author URL.
Cashmore L, Uomini N, Chapelain A (2008). The evolution of handedness in humans and great apes: a review and current issues.
J Anthropol Sci,
86, 7-35.
Abstract:
The evolution of handedness in humans and great apes: a review and current issues.
Population-level right-handedness is a defining characteristic of humans. Despite extensive research, we still do not know the conditions or timing of its emergence in human evolution. We present a review of research into the origins of handedness, based on fossil and archaeological data for hand preference and great ape hand-use. The data show that skeletal asymmetries in arm and hand bones supporting a rightsided dominance were present at least in the genus Homo, although data are more robust for Neanderthals. The evidence from tool-use, production, and cave art confirms that right-hand preference was established in Neanderthals and was maintained until the present. The great apes can provide real-life models for testing the conditions that facilitate or enhance hand preference at both the individual and group levels. The database on great ape hand-use indicates that they do exhibit hand preferences, especially in complex tasks. However, their preferences vary between tasks, and while group-level biases have occasionally been reported, no human-like handedness bias has been found. We discuss the methodological problems encountered in these approaches. Shared problems include a lack of agreed terminology both within and between disciplines, small sample sizes, interpretation biases and a failure to replicate experiments. In general, there is a paucity of fossil material, with poor preservation hampering traditional metric methods. The archaeological data are often founded on unreliable methods. The primate database is plagued by the use of measures that could be inappropriate for revealing hand preference, and by methodological inconsistencies between studies. We emphasise the need to standardise the methods to allow between studies and species comparisons. We propose that when referring to "handedness" it is more appropriate to use the terms "hand preference" and "hand use", to avoid confusion with each discipline's own definition of handedness.
Abstract.
Author URL.
Publications by year
2014
Nelson E, Cashmore L (2014). Associations between digit ratio and musculoskeletal stress markers in the hand in three species of ape.
Author URL.
2013
Cashmore LA, Zakrzewski SR (2013). Assessment of musculoskeletal stress marker development in the hand.
International Journal of Osteoarchaeology,
23(3), 334-347.
Abstract:
Assessment of musculoskeletal stress marker development in the hand
The analysis of musculoskeletal stress marker (MSM) development is a commonly employed tool in osteological surveys and is used to infer patterns of occupational activity and societal organisation in archaeological populations. Although the majority of research into upper limb MSMs has focused on the bones of the arm, the bones of the hand have been conspicuous by their absence. This is likely to be due to methodological issues surrounding the study of hand bones and a presumed lack of variation in MSM development in this area. To date, there have been no systematic studies investigating the presence and variation in MSM morphology for the muscles of the human hand. To address this issue, a presence/absence scoring system was developed for twelve sites of muscle origin and insertion in the metacarpals and phalanges, which was used to determine bilateral asymmetry in the hands of 31 individuals from the Naval Hospital Cemetery site in Greenwich, London. Analysis found observable variation in MSM development between and within the hands, which could be used to determine patterns of asymmetry within the sample. Comparisons with MSM scores from the humeri of these individuals indicate a differentiation in MSM development and asymmetry between these anatomical regions. Levels of asymmetry in the hands and humeri were generally low, with only the dorsal interossei displaying statistically significant asymmetry. Subsequent upper limb MSM research will benefit from the inclusion of data from the hands. These results do not support the continued use of the humerus as a proxy for MSM expression across the upper limb as a whole and suggest that important information regarding behavioural asymmetry in the hands is being lost because of the continual exclusion of this anatomical unit from MSM research. © 2011 John Wiley & Sons, Ltd.
Abstract.
Cashmore L (2013). Human Evolution in the Quaternary. In Elias S, Mock C (Eds.) Encyclopedia of Quaternary Science, Amsterdam: Elsevier, 135-145.
2011
Nelson E, Rolian C, Cashmore LA, Shultz S (2011). Digit ratios predict polygyny in early apes, Ardipithecus, Neanderthals and early modern humans but not in Australopithecus.
Proceedings of the Royal Society of London: Biological Sciences,
278(1711), 1556-1563.
Abstract:
Digit ratios predict polygyny in early apes, Ardipithecus, Neanderthals and early modern humans but not in Australopithecus
Social behaviour of fossil hominoid species is notoriously difficult to predict owing to difficulties in estimating body size dimorphism from fragmentary remains and, in hominins, low canine size dimorphism. Recent studies have shown that the second-to-fourth digit ratio (2D : 4D), a putative biomarker for prenatal androgen effects (PAEs), covaries with intra-sexual competition and social systems across haplorrhines; non-pair-bonded polygynous taxa have significantly lower 2D : 4D ratios (high PAE) than pair-bonded monogamous species. Here, we use proximal phalanx ratios of extant and fossil specimens to reconstruct the social systems of extinct hominoids. Pierolapithecus catalaunicus, Hispanopithecus laietanus and Ardipithecus ramidus have ratios consistent with polygynous extant species, whereas the ratio of Australopithecus afarensis is consistent with monogamous extant species. The early anatomically modern human Qafzeh 9 and Neanderthals have lower digit ratios than most contemporary human populations, indicating increased androgenization and possibly higher incidence of polygyny. Although speculative owing to small sample sizes, these results suggest that digit ratios represent a supplementary approach for elucidating the social systems of fossil hominins.
Abstract.
2010
Cashmore LA, Zakrzewski SR (2010). Assessment of musculoskeletal stress markers in the hand.
Author URL.
2009
Cashmore L (2009). Can hominin 'handedness' be accurately assessed?.
Ann Hum Biol,
36(5), 624-641.
Abstract:
Can hominin 'handedness' be accurately assessed?
The expression of a strong, population-level right hand preference has, to date only been unequivocally identified in Homo sapiens and is often considered to be unique to this species. For this reason, and because of purported co-evolutionary links between this trait and language capabilities in modern humans, the identification of hand preference in the hominin fossil record has long been of interest to researchers studying the evolution of 'handedness' within the genus Homo. Identifying hand preference in skeletal samples, however, is not straightforward. Problems arise from difficulties in determining the precise nature of the relationship between hand use and bone morphology, the methods by which hand preference is assessed, the paucity of material available for study, and even what is meant by the term 'handedness'. Various attempts have been made to address these issues, encompassing a range of methodological approaches, such as comparisons of osteological techniques, studies of prehistoric material culture and ethnographic analysis of hand use behaviours in modern hunter-gatherer societies and non-human primate groups. What such research suggests is that hand preference is a complex phenomenon, in both extant and extinct groups, and in order to assess its expression in extinct populations care must be paid to the questions asked of the available material and the methodologies used to answer them.
Abstract.
Author URL.
Cashmore LA, Zakrzewski SR (2009). Identifying skeletal upper limb bilateral asymmetry in great apes.
AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, 104-104.
Author URL.
2008
Cashmore LA, Zakrzewski SR (2008). Assessment of upper limb bilateral asymmetry and implications for the evolution of handedness.
Author URL.
Cashmore L, Uomini N, Chapelain A (2008). The evolution of handedness in humans and great apes: a review and current issues.
J Anthropol Sci,
86, 7-35.
Abstract:
The evolution of handedness in humans and great apes: a review and current issues.
Population-level right-handedness is a defining characteristic of humans. Despite extensive research, we still do not know the conditions or timing of its emergence in human evolution. We present a review of research into the origins of handedness, based on fossil and archaeological data for hand preference and great ape hand-use. The data show that skeletal asymmetries in arm and hand bones supporting a rightsided dominance were present at least in the genus Homo, although data are more robust for Neanderthals. The evidence from tool-use, production, and cave art confirms that right-hand preference was established in Neanderthals and was maintained until the present. The great apes can provide real-life models for testing the conditions that facilitate or enhance hand preference at both the individual and group levels. The database on great ape hand-use indicates that they do exhibit hand preferences, especially in complex tasks. However, their preferences vary between tasks, and while group-level biases have occasionally been reported, no human-like handedness bias has been found. We discuss the methodological problems encountered in these approaches. Shared problems include a lack of agreed terminology both within and between disciplines, small sample sizes, interpretation biases and a failure to replicate experiments. In general, there is a paucity of fossil material, with poor preservation hampering traditional metric methods. The archaeological data are often founded on unreliable methods. The primate database is plagued by the use of measures that could be inappropriate for revealing hand preference, and by methodological inconsistencies between studies. We emphasise the need to standardise the methods to allow between studies and species comparisons. We propose that when referring to "handedness" it is more appropriate to use the terms "hand preference" and "hand use", to avoid confusion with each discipline's own definition of handedness.
Abstract.
Author URL.
2007
Zakrzewski SR, Cashmore LA, Pomeroy EE (2007). Activity and asymmetry at Islamic Ecija (Spain).
AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, 255-255.
Author URL.
Cashmore LA, Zakrzewski SR (2007). Hand morphology, hand preference and laterality.
AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, 84-84.
Author URL.