CAUGHT in the act: a worker ant Sphecomyrma freyi preserved in amber thought to be some 80 millio... more CAUGHT in the act: a worker ant Sphecomyrma freyi preserved in amber thought to be some 80 million years old. Taken from Journey to the Ants: A Story of Scientific Exploration by Bert Hiilldobler and Edward 0. Wilson, who, according to Deborah M. Gordon in a review of the book last year, "have done for ants what Levis did for denim" (Nature 373, 292; 1994).
Bulletins et Mémoires de la Société d'Anthropologie de Paris, 2018
During the second half of the twentieth century, the evidence that Africa was central to hominin ... more During the second half of the twentieth century, the evidence that Africa was central to hominin evolution became overwhelming. The earliest occurrences of most of the fossil hominin taxa and lithic technologies are to be found in Africa, and there is also strong evidence that humans are closely related to African apes, and that the genetic origins of modern humans lie in Africa. The aim of this article is to consider the possible evolutionary and ecological basis for this — why should Africa be so central? After considering biases in the record that might promote an African record, this article uses evolutionary geography – the spatial and distributional properties of the evolutionary process — to consider the factors that lead to higher rates of speciation, novelty and dispersals, as well as the way in which the African ecological context is structured and changes through time. Critical factors identified are the variable role of the Sahara, the different extent of the Afrotropica...
Expert field palaeontologist who made many key discoveries about early human evolution in East Af... more Expert field palaeontologist who made many key discoveries about early human evolution in East Africa.
Philosophical Transactions of the Royal Society B: Biological Sciences, 2016
Evolutionary problems are often considered in terms of ‘origins', and research in human evolu... more Evolutionary problems are often considered in terms of ‘origins', and research in human evolution seen as a search for human origins. However, evolution, including human evolution, is a process of transitions from one state to another, and so questions are best put in terms of understanding the nature of those transitions. This paper discusses how the contributions to the themed issue ‘Major transitions in human evolution’ throw light on the pattern of change in hominin evolution. Four questions are addressed: (1) Is there a major divide between early (australopithecine) and later ( Homo ) evolution? (2) Does the pattern of change fit a model of short transformations, or gradual evolution? (3) Why is the role of Africa so prominent? (4) How are different aspects of adaptation—genes, phenotypes and behaviour—integrated across the transitions? The importance of developing technologies and approaches and the enduring role of fieldwork are emphasized. This article is part of the the...
This paper reports on the work carried out during the 2009 field season of the prehistory sub-the... more This paper reports on the work carried out during the 2009 field season of the prehistory sub-theme of the Desert Migrations Project. The work consisted of detailed survey and small-scale excavations in two wadis that drain the Messak Settafet, near the town of Jarma. Both wadis were found to contain evidence of Palaeolithic and Neolithic occupation, as well as of having been used as migratory routes between the Ubari and Murzuq sand seas. One of the wadis (WJAR-E-O1) was surveyed intensely along a few kilometers of its tributary margins. This revealed archaeological material ranging from Oldowan (Mode 1) to historic. The distribution of the various industries and structures had a distinct spatial patterning; the Palaeolithic scatters were spatially discrete, but Holocene remains were often found superimposed on earlier industries. Among the finds were a spatially discrete Oldowan assemblage, an extensive Acheulean industry which included the exploitation of fossil wood as a raw mat...
The palaeoanthropological and geomorphological sub-projects of the Desert Migrations Project (DMP... more The palaeoanthropological and geomorphological sub-projects of the Desert Migrations Project (DMP) focus on the Pleistocene and early Holocene environment and prehistory of Fazzan so as to assess the timing and extent of hominin and human movement across the Sahara through time. This paper reports on the findings of the 2008 field season, with a focus on the prehistoric evidence along the northern margin of the Ubari sand sea.The geomorphological record of the area preserves evidence of at least five past episodes of lake formation. The exact chronology of these, as well as the spatial extent of these lakes, remains the focus of further study.The archaeological record of hominin and human occupation of Fazzan prior to the establishment of the Garamantian civilisation is extraordinarily rich. Between 2007 and 2008, the DMP palaeoanthropological project surveyed thirty-five localities along the northern margin of the Ubari sand sea, recording a range of assemblages spanning all Palaeo...
Parent-of-origin effects have been found to influence the mammalian brain and cognition and have ... more Parent-of-origin effects have been found to influence the mammalian brain and cognition and have been specifically implicated in the development of human social cognition and theory of mind. The experimental design in this study was developed to detect parent-of-origin effects on theory of mind, as measured by the 'Reading the mind in the eyes' (Eyes) task. Eyes scores were also entered into a principal components analysis with measures of empathy, social skills and executive function, in order to determine what aspect of theory of mind Eyes is measuring. Maternal and paternal influences on Eyes scores were compared using correlations between pairs of full (70 pairs), maternal (25 pairs) and paternal siblings (15 pairs). Structural equation modelling supported a maternal influence on Eyes scores over the normal range but not low-scoring outliers, and also a sex-specific influence on males acting to decrease male Eyes scores. It was not possible to differentiate between genet...
The same continued. F. 10-11.30 The same continued. W. 9-11 The same continued. M. 11 The same co... more The same continued. F. 10-11.30 The same continued. W. 9-11 The same continued. M. 11 The same continued. Th. 10, 12 The same continued. Tu. 11 (weeks 1-4) The same continued. W. 9-11 The same continued. F. 10-12
Many plants and animals are capable of developing in a variety of ways, forming characteristics t... more Many plants and animals are capable of developing in a variety of ways, forming characteristics that are well adapted to the environments in which they are likely to live. In adverse circumstances, for example, small size and slow metabolism can facilitate survival, whereas larger size and more rapid metabolism have advantages for reproductive success when resources are more abundant. Often these characteristics are induced in early life or are even set by cues to which their parents or grandparents were exposed. Individuals developmentally adapted to one environment may, however, be at risk when exposed to another when they are older. The biological evidence may be relevant to the understanding of human development and susceptibility to disease. As the nutritional state of many human mothers has improved around the world, the characteristics of their offspring-such as body size and metabolism-have also changed. Responsiveness to their mothers' condition before birth may generally prepare individuals so that they are best suited to the environment forecast by cues available in early life. Paradoxically, however, rapid improvements in nutrition and other environmental conditions may have damaging effects on the health of those people whose parents and grandparents lived in impoverished conditions. A fuller understanding of patterns of human plasticity in response to early nutrition and other environmental factors will have implications for the administration of public health.
Evolutionary Anthropology: Issues, News, and Reviews, 2005
39 Steudel K, Beattie J (n.d.) Does limb length predict the energetic cost of locomotion in mamma... more 39 Steudel K, Beattie J (n.d.) Does limb length predict the energetic cost of locomotion in mammals? J Zoo1 (London), in press. 40 Cavanagh PR, Williams KR (1982) The effect of stride length variation on oxygen uptake during distance running. Med Sci Sports Exer 14:30-35. 41 Cotes JE, Meade F (1960) The energy expenditure and mechanical energy demand in walking. Ergonomics 3:97-120. 42 Harris M, Steudel K (1993) Hindlimb length correlates in the Carnivora. Am Zoo1 33:74A. 43 Garland T Jr, Janis CM (1993) Does metatarsal/femur ratio predict maximal running speed in cursorial mammals? J Zoo1 (London) 229:133-15 1. 44 Tsuji JS, Huey RB, Van Berkum FH, Garland T Jr, Shaw RG (1989) Locomotor performance of hatchling fence lizards (Sceloporus occidentalis): Quantitative genetics and morphometric correlates. Evol Ecol 3:240-252. 45 Garland T Jr (1985) Ontogenetic and individual variation in size, shape and speed in the Australian agamid lizard arnphibolurus nuchalis. J Zoo1 (London) 207:425-439. 46 Losos JB (1990) The evolution of form and function: Morphology and locomotor performance in West Indian Anolis lizards. Evolution 44:1189-1203. 47 Garland T Jr (1984) Physiological correlates of locomotory performance in a lizard:
The origins of modern humans have been the central debate in palaeoanthropology during the last d... more The origins of modern humans have been the central debate in palaeoanthropology during the last decade. We examine the problem in the context of the history of anthropology, the accumulating evidence for a recent African origin, and evolutionary mechanisms. Using a historical perspective, we show that the current controversy is a continuation of older conflicts and as such relates to questions of both origins and diversity. However, a better fossil sample, improved dates, and genetic data have introduced new perspectives, and we argue that evolutionary geography, which uses spatial distributions of populations as the basis for integrating contingent, adaptive, and demographic aspects of microevolutionary change, provides an appropriate theoretical framework. Evolutionary geography is used to explore two events: the evolution of the Neanderthal lineage and the relationship between an ancestral bottleneck with the evolution of anatomically modern humans and their diversity. We argue that the Neanderthal and modern lineages share a common ancestor in an African population between 350,000 and 250,000 years ago rather than in the earlier Middle Pleistocene; this ancestral population, which developed mode 3 technology (Levallois/Middle Stone Age), dispersed across Africa and western Eurasia in a warmer period prior to independent evolution towards Neanderthals and modern humans in stage 6. Both lineages would thus share a common large-brained ancestry, a technology, and a history of dispersal. They differ in the conditions under which they subsequently evolved and their ultimate evolutionary fate. Both lineages illustrate the repeated interactions of the glacial cycles, the role of cold-arid periods in producing fragmentation of populations, bottlenecks, and isolation, and the role of warmer periods in producing trans-African dispersals.
Philosophical transactions of the Royal Society of London. Series B, Biological sciences, Jul 5, 2016
Humans are uniquely unique, in terms of the extreme differences between them and other living org... more Humans are uniquely unique, in terms of the extreme differences between them and other living organisms, and the impact they are having on the biosphere. The evolution of humans can be seen, as has been proposed, as one of the major transitions in evolution, on a par with the origins of multicellular organisms or the eukaryotic cell (Maynard Smith & Szathmáry 1997 Major transitions in evolution). Major transitions require the evolution of greater complexity and the emergence of new evolutionary levels or processes. Does human evolution meet these conditions? I explore the diversity of evidence on the nature of transitions in human evolution. Four levels of transition are proposed-baseline, novel taxa, novel adaptive zones and major transitions-and the pattern of human evolution considered in the light of these. The primary conclusions are that changes in human evolution occur continuously and cumulatively; that novel taxa and the appearance of new adaptations are not clustered very ...
The Central Sahara is an area of great interest in human evolution partly because it currently ex... more The Central Sahara is an area of great interest in human evolution partly because it currently exhibits some of the most extreme desert conditions in the world, and partly because of its geographical location e in a nexus of relationships with sub-Saharan Africa, Mediterranean Africa, and Western Asia. Fieldwork in the Ubari sand sea and the Messak (Fazzan, Libya) through the Desert Migrations Project has identified numerous Middle Stone Age (MSA) sites both along the shores of interdunal palaeolakes and on the mountainous plateaus of the area, such as the Messak Settafet. In this paper, we describe some of the evidence for the MSA in Fazzan, and discuss it in the context of the African MSA more generally. We show that this MSA record exhibits considerable typological and technological variation, and discuss the implications for hypotheses relating to the colonization of desert environment and the expansion of hominins out of sub-Saharan Africa.
Background: Parent-of-origin effects have been found to influence the mammalian brain and cogniti... more Background: Parent-of-origin effects have been found to influence the mammalian brain and cognition and have been specifically implicated in the development of human social cognition and theory of mind. The experimental design in this study was developed to detect parent-of-origin effects on theory of mind, as measured by the 'Reading the mind in the eyes' (Eyes) task. Eyes scores were also entered into a principal components analysis with measures of empathy, social skills and executive function, in order to determine what aspect of theory of mind Eyes is measuring. Methodology/Principal Findings: Maternal and paternal influences on Eyes scores were compared using correlations between pairs of full (70 pairs), maternal (25 pairs) and paternal siblings (15 pairs). Structural equation modelling supported a maternal influence on Eyes scores over the normal range but not low-scoring outliers, and also a sex-specific influence on males acting to decrease male Eyes scores. It was not possible to differentiate between genetic and environmental influences in this particular sample because maternal siblings tended to be raised together while paternal siblings were raised apart. The principal components analysis found Eyes was associated with measures of executive function, principally behavioural inhibition and attention, rather than empathy or social skills. Conclusions/Significance: In conclusion, the results suggest a maternal influence on Eye scores in the normal range and a sex-specific influence acting to reduce scores in males. This influence may act via aspects of executive function such as behavioural inhibition and attention. There may be different influences acting to produce the lowest Eyes scores which implies that the heratibility and/or maternal influence on poor theory of mind skills may be qualitatively different to the influence on the normal range.
Evolutionary Ecology of Fossil Hominids RA Foley 5 5.1. INTRODUCTION Behavioral ecology has devel... more Evolutionary Ecology of Fossil Hominids RA Foley 5 5.1. INTRODUCTION Behavioral ecology has developed in the context of microevolution. Its focus is the pattern of variation within and between living populations. Behavioral ecologists ...
Human mate choice is influenced by limb proportions. Previous work has focused on leg-to-body rat... more Human mate choice is influenced by limb proportions. Previous work has focused on leg-to-body ratio (LBR) as a determinant of male attractiveness and found a preference for limbs that are close to, or slightly above, the average. We investigated the influence of two other key aspects of limb morphology: arm-to-body ratio (ABR) and intra-limb ratio (IR). In three studies of heterosexual women from the USA, we tested the attractiveness of male physiques that varied in LBR, ABR and IR, using figures that ranged from -3 to +3 standard deviations from the population mean. We replicated previous work by finding that the optimally attractive LBR is approximately 0.5 standard deviations above the baseline. We also found a weak effect of IR, with evidence of a weak preference for the baseline proportions. In contrast, there was no effect of ABR on attractiveness, and no interactions between the effects of LBR, ABR and IR. Our results indicate that ABR is not an important determinant of human...
CAUGHT in the act: a worker ant Sphecomyrma freyi preserved in amber thought to be some 80 millio... more CAUGHT in the act: a worker ant Sphecomyrma freyi preserved in amber thought to be some 80 million years old. Taken from Journey to the Ants: A Story of Scientific Exploration by Bert Hiilldobler and Edward 0. Wilson, who, according to Deborah M. Gordon in a review of the book last year, "have done for ants what Levis did for denim" (Nature 373, 292; 1994).
Bulletins et Mémoires de la Société d'Anthropologie de Paris, 2018
During the second half of the twentieth century, the evidence that Africa was central to hominin ... more During the second half of the twentieth century, the evidence that Africa was central to hominin evolution became overwhelming. The earliest occurrences of most of the fossil hominin taxa and lithic technologies are to be found in Africa, and there is also strong evidence that humans are closely related to African apes, and that the genetic origins of modern humans lie in Africa. The aim of this article is to consider the possible evolutionary and ecological basis for this — why should Africa be so central? After considering biases in the record that might promote an African record, this article uses evolutionary geography – the spatial and distributional properties of the evolutionary process — to consider the factors that lead to higher rates of speciation, novelty and dispersals, as well as the way in which the African ecological context is structured and changes through time. Critical factors identified are the variable role of the Sahara, the different extent of the Afrotropica...
Expert field palaeontologist who made many key discoveries about early human evolution in East Af... more Expert field palaeontologist who made many key discoveries about early human evolution in East Africa.
Philosophical Transactions of the Royal Society B: Biological Sciences, 2016
Evolutionary problems are often considered in terms of ‘origins', and research in human evolu... more Evolutionary problems are often considered in terms of ‘origins', and research in human evolution seen as a search for human origins. However, evolution, including human evolution, is a process of transitions from one state to another, and so questions are best put in terms of understanding the nature of those transitions. This paper discusses how the contributions to the themed issue ‘Major transitions in human evolution’ throw light on the pattern of change in hominin evolution. Four questions are addressed: (1) Is there a major divide between early (australopithecine) and later ( Homo ) evolution? (2) Does the pattern of change fit a model of short transformations, or gradual evolution? (3) Why is the role of Africa so prominent? (4) How are different aspects of adaptation—genes, phenotypes and behaviour—integrated across the transitions? The importance of developing technologies and approaches and the enduring role of fieldwork are emphasized. This article is part of the the...
This paper reports on the work carried out during the 2009 field season of the prehistory sub-the... more This paper reports on the work carried out during the 2009 field season of the prehistory sub-theme of the Desert Migrations Project. The work consisted of detailed survey and small-scale excavations in two wadis that drain the Messak Settafet, near the town of Jarma. Both wadis were found to contain evidence of Palaeolithic and Neolithic occupation, as well as of having been used as migratory routes between the Ubari and Murzuq sand seas. One of the wadis (WJAR-E-O1) was surveyed intensely along a few kilometers of its tributary margins. This revealed archaeological material ranging from Oldowan (Mode 1) to historic. The distribution of the various industries and structures had a distinct spatial patterning; the Palaeolithic scatters were spatially discrete, but Holocene remains were often found superimposed on earlier industries. Among the finds were a spatially discrete Oldowan assemblage, an extensive Acheulean industry which included the exploitation of fossil wood as a raw mat...
The palaeoanthropological and geomorphological sub-projects of the Desert Migrations Project (DMP... more The palaeoanthropological and geomorphological sub-projects of the Desert Migrations Project (DMP) focus on the Pleistocene and early Holocene environment and prehistory of Fazzan so as to assess the timing and extent of hominin and human movement across the Sahara through time. This paper reports on the findings of the 2008 field season, with a focus on the prehistoric evidence along the northern margin of the Ubari sand sea.The geomorphological record of the area preserves evidence of at least five past episodes of lake formation. The exact chronology of these, as well as the spatial extent of these lakes, remains the focus of further study.The archaeological record of hominin and human occupation of Fazzan prior to the establishment of the Garamantian civilisation is extraordinarily rich. Between 2007 and 2008, the DMP palaeoanthropological project surveyed thirty-five localities along the northern margin of the Ubari sand sea, recording a range of assemblages spanning all Palaeo...
Parent-of-origin effects have been found to influence the mammalian brain and cognition and have ... more Parent-of-origin effects have been found to influence the mammalian brain and cognition and have been specifically implicated in the development of human social cognition and theory of mind. The experimental design in this study was developed to detect parent-of-origin effects on theory of mind, as measured by the 'Reading the mind in the eyes' (Eyes) task. Eyes scores were also entered into a principal components analysis with measures of empathy, social skills and executive function, in order to determine what aspect of theory of mind Eyes is measuring. Maternal and paternal influences on Eyes scores were compared using correlations between pairs of full (70 pairs), maternal (25 pairs) and paternal siblings (15 pairs). Structural equation modelling supported a maternal influence on Eyes scores over the normal range but not low-scoring outliers, and also a sex-specific influence on males acting to decrease male Eyes scores. It was not possible to differentiate between genet...
The same continued. F. 10-11.30 The same continued. W. 9-11 The same continued. M. 11 The same co... more The same continued. F. 10-11.30 The same continued. W. 9-11 The same continued. M. 11 The same continued. Th. 10, 12 The same continued. Tu. 11 (weeks 1-4) The same continued. W. 9-11 The same continued. F. 10-12
Many plants and animals are capable of developing in a variety of ways, forming characteristics t... more Many plants and animals are capable of developing in a variety of ways, forming characteristics that are well adapted to the environments in which they are likely to live. In adverse circumstances, for example, small size and slow metabolism can facilitate survival, whereas larger size and more rapid metabolism have advantages for reproductive success when resources are more abundant. Often these characteristics are induced in early life or are even set by cues to which their parents or grandparents were exposed. Individuals developmentally adapted to one environment may, however, be at risk when exposed to another when they are older. The biological evidence may be relevant to the understanding of human development and susceptibility to disease. As the nutritional state of many human mothers has improved around the world, the characteristics of their offspring-such as body size and metabolism-have also changed. Responsiveness to their mothers' condition before birth may generally prepare individuals so that they are best suited to the environment forecast by cues available in early life. Paradoxically, however, rapid improvements in nutrition and other environmental conditions may have damaging effects on the health of those people whose parents and grandparents lived in impoverished conditions. A fuller understanding of patterns of human plasticity in response to early nutrition and other environmental factors will have implications for the administration of public health.
Evolutionary Anthropology: Issues, News, and Reviews, 2005
39 Steudel K, Beattie J (n.d.) Does limb length predict the energetic cost of locomotion in mamma... more 39 Steudel K, Beattie J (n.d.) Does limb length predict the energetic cost of locomotion in mammals? J Zoo1 (London), in press. 40 Cavanagh PR, Williams KR (1982) The effect of stride length variation on oxygen uptake during distance running. Med Sci Sports Exer 14:30-35. 41 Cotes JE, Meade F (1960) The energy expenditure and mechanical energy demand in walking. Ergonomics 3:97-120. 42 Harris M, Steudel K (1993) Hindlimb length correlates in the Carnivora. Am Zoo1 33:74A. 43 Garland T Jr, Janis CM (1993) Does metatarsal/femur ratio predict maximal running speed in cursorial mammals? J Zoo1 (London) 229:133-15 1. 44 Tsuji JS, Huey RB, Van Berkum FH, Garland T Jr, Shaw RG (1989) Locomotor performance of hatchling fence lizards (Sceloporus occidentalis): Quantitative genetics and morphometric correlates. Evol Ecol 3:240-252. 45 Garland T Jr (1985) Ontogenetic and individual variation in size, shape and speed in the Australian agamid lizard arnphibolurus nuchalis. J Zoo1 (London) 207:425-439. 46 Losos JB (1990) The evolution of form and function: Morphology and locomotor performance in West Indian Anolis lizards. Evolution 44:1189-1203. 47 Garland T Jr (1984) Physiological correlates of locomotory performance in a lizard:
The origins of modern humans have been the central debate in palaeoanthropology during the last d... more The origins of modern humans have been the central debate in palaeoanthropology during the last decade. We examine the problem in the context of the history of anthropology, the accumulating evidence for a recent African origin, and evolutionary mechanisms. Using a historical perspective, we show that the current controversy is a continuation of older conflicts and as such relates to questions of both origins and diversity. However, a better fossil sample, improved dates, and genetic data have introduced new perspectives, and we argue that evolutionary geography, which uses spatial distributions of populations as the basis for integrating contingent, adaptive, and demographic aspects of microevolutionary change, provides an appropriate theoretical framework. Evolutionary geography is used to explore two events: the evolution of the Neanderthal lineage and the relationship between an ancestral bottleneck with the evolution of anatomically modern humans and their diversity. We argue that the Neanderthal and modern lineages share a common ancestor in an African population between 350,000 and 250,000 years ago rather than in the earlier Middle Pleistocene; this ancestral population, which developed mode 3 technology (Levallois/Middle Stone Age), dispersed across Africa and western Eurasia in a warmer period prior to independent evolution towards Neanderthals and modern humans in stage 6. Both lineages would thus share a common large-brained ancestry, a technology, and a history of dispersal. They differ in the conditions under which they subsequently evolved and their ultimate evolutionary fate. Both lineages illustrate the repeated interactions of the glacial cycles, the role of cold-arid periods in producing fragmentation of populations, bottlenecks, and isolation, and the role of warmer periods in producing trans-African dispersals.
Philosophical transactions of the Royal Society of London. Series B, Biological sciences, Jul 5, 2016
Humans are uniquely unique, in terms of the extreme differences between them and other living org... more Humans are uniquely unique, in terms of the extreme differences between them and other living organisms, and the impact they are having on the biosphere. The evolution of humans can be seen, as has been proposed, as one of the major transitions in evolution, on a par with the origins of multicellular organisms or the eukaryotic cell (Maynard Smith & Szathmáry 1997 Major transitions in evolution). Major transitions require the evolution of greater complexity and the emergence of new evolutionary levels or processes. Does human evolution meet these conditions? I explore the diversity of evidence on the nature of transitions in human evolution. Four levels of transition are proposed-baseline, novel taxa, novel adaptive zones and major transitions-and the pattern of human evolution considered in the light of these. The primary conclusions are that changes in human evolution occur continuously and cumulatively; that novel taxa and the appearance of new adaptations are not clustered very ...
The Central Sahara is an area of great interest in human evolution partly because it currently ex... more The Central Sahara is an area of great interest in human evolution partly because it currently exhibits some of the most extreme desert conditions in the world, and partly because of its geographical location e in a nexus of relationships with sub-Saharan Africa, Mediterranean Africa, and Western Asia. Fieldwork in the Ubari sand sea and the Messak (Fazzan, Libya) through the Desert Migrations Project has identified numerous Middle Stone Age (MSA) sites both along the shores of interdunal palaeolakes and on the mountainous plateaus of the area, such as the Messak Settafet. In this paper, we describe some of the evidence for the MSA in Fazzan, and discuss it in the context of the African MSA more generally. We show that this MSA record exhibits considerable typological and technological variation, and discuss the implications for hypotheses relating to the colonization of desert environment and the expansion of hominins out of sub-Saharan Africa.
Background: Parent-of-origin effects have been found to influence the mammalian brain and cogniti... more Background: Parent-of-origin effects have been found to influence the mammalian brain and cognition and have been specifically implicated in the development of human social cognition and theory of mind. The experimental design in this study was developed to detect parent-of-origin effects on theory of mind, as measured by the 'Reading the mind in the eyes' (Eyes) task. Eyes scores were also entered into a principal components analysis with measures of empathy, social skills and executive function, in order to determine what aspect of theory of mind Eyes is measuring. Methodology/Principal Findings: Maternal and paternal influences on Eyes scores were compared using correlations between pairs of full (70 pairs), maternal (25 pairs) and paternal siblings (15 pairs). Structural equation modelling supported a maternal influence on Eyes scores over the normal range but not low-scoring outliers, and also a sex-specific influence on males acting to decrease male Eyes scores. It was not possible to differentiate between genetic and environmental influences in this particular sample because maternal siblings tended to be raised together while paternal siblings were raised apart. The principal components analysis found Eyes was associated with measures of executive function, principally behavioural inhibition and attention, rather than empathy or social skills. Conclusions/Significance: In conclusion, the results suggest a maternal influence on Eye scores in the normal range and a sex-specific influence acting to reduce scores in males. This influence may act via aspects of executive function such as behavioural inhibition and attention. There may be different influences acting to produce the lowest Eyes scores which implies that the heratibility and/or maternal influence on poor theory of mind skills may be qualitatively different to the influence on the normal range.
Evolutionary Ecology of Fossil Hominids RA Foley 5 5.1. INTRODUCTION Behavioral ecology has devel... more Evolutionary Ecology of Fossil Hominids RA Foley 5 5.1. INTRODUCTION Behavioral ecology has developed in the context of microevolution. Its focus is the pattern of variation within and between living populations. Behavioral ecologists ...
Human mate choice is influenced by limb proportions. Previous work has focused on leg-to-body rat... more Human mate choice is influenced by limb proportions. Previous work has focused on leg-to-body ratio (LBR) as a determinant of male attractiveness and found a preference for limbs that are close to, or slightly above, the average. We investigated the influence of two other key aspects of limb morphology: arm-to-body ratio (ABR) and intra-limb ratio (IR). In three studies of heterosexual women from the USA, we tested the attractiveness of male physiques that varied in LBR, ABR and IR, using figures that ranged from -3 to +3 standard deviations from the population mean. We replicated previous work by finding that the optimally attractive LBR is approximately 0.5 standard deviations above the baseline. We also found a weak effect of IR, with evidence of a weak preference for the baseline proportions. In contrast, there was no effect of ABR on attractiveness, and no interactions between the effects of LBR, ABR and IR. Our results indicate that ABR is not an important determinant of human...
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Papers by Robert Foley