A hypothesis to explain the role of meat-eating in human evolution

Milton, Katharine

doi:10.1002/(sici)1520-6505(1999)8:1<11::aid-evan6>3.0.co;2-m

Cited by 259 publications

(106 citation statements)

References 58 publications

Supporting

Mentioning

105

Contrasting

Order By: Relevance

“…Our study also relates to hypotheses that historic diets and/or changes in lipid metabolism influenced the evolution of numerous human traits [2,12,18,55,64,65,80-85]. To further explore such hypotheses, it will be necessary to determine if the RBC phytanic acid profiles in our cohort extend to other cell types.…”

Section: Discussionmentioning

confidence: 92%

Identification of differences in human and great ape phytanic acid metabolism that could influence gene expression profiles and physiological functions

et al. 2010

View full text Add to dashboard Cite

BackgroundIt has been proposed that anatomical differences in human and great ape guts arose in response to species-specific diets and energy demands. To investigate functional genomic consequences of these differences, we compared their physiological levels of phytanic acid, a branched chain fatty acid that can be derived from the microbial degradation of chlorophyll in ruminant guts. Humans who accumulate large stores of phytanic acid commonly develop cerebellar ataxia, peripheral polyneuropathy, and retinitis pigmentosa in addition to other medical conditions. Furthermore, phytanic acid is an activator of the PPAR-alpha transcription factor that influences the expression of genes relevant to lipid metabolism.ResultsDespite their trace dietary phytanic acid intake, all great ape species had elevated red blood cell (RBC) phytanic acid levels relative to humans on diverse diets. Unlike humans, chimpanzees showed sexual dimorphism in RBC phytanic acid levels, which were higher in males relative to females. Cultured skin fibroblasts from all species had a robust capacity to degrade phytanic acid. We provide indirect evidence that great apes, in contrast to humans, derive significant amounts of phytanic acid from the hindgut fermentation of plant materials. This would represent a novel reduction of metabolic activity in humans relative to the great apes.ConclusionWe identified differences in the physiological levels of phytanic acid in humans and great apes and propose this is causally related to their gut anatomies and microbiomes. Phytanic acid levels could contribute to cross-species and sex-specific differences in human and great ape transcriptomes, especially those related to lipid metabolism. Based on the medical conditions caused by phytanic acid accumulation, we suggest that differences in phytanic acid metabolism could influence the functions of human and great ape nervous, cardiovascular, and skeletal systems.

show abstract

Section: Discussionmentioning

confidence: 92%

Identification of differences in human and great ape phytanic acid metabolism that could influence gene expression profiles and physiological functions

et al. 2010

View full text Add to dashboard Cite

show abstract

“…ergaster . On one hand, early Homo specimens show low scratch densities suggestive of chewing soft foods, consistent with meat consumption as a major dietary source and increased brain volume [28,142]. On the other hand, H .…”

Section: Discussionmentioning

confidence: 99%

Testing Dietary Hypotheses of East African Hominines Using Buccal Dental Microwear Data

et al. 2016

View full text Add to dashboard Cite

There is much debate on the dietary adaptations of the robust hominin lineages during the Pliocene-Pleistocene transition. It has been argued that the shift from C3 to C4 ecosystems in Africa was the main factor responsible for the robust dental and facial anatomical adaptations of Paranthropus taxa, which might be indicative of the consumption of fibrous, abrasive plant foods in open environments. However, occlusal dental microwear data fail to provide evidence of such dietary adaptations and are not consistent with isotopic evidence that supports greater C4 food intake for the robust clades than for the gracile australopithecines. We provide evidence from buccal dental microwear data that supports softer dietary habits than expected for P. aethiopicus and P. boisei based both on masticatory apomorphies and isotopic analyses. On one hand, striation densities on the buccal enamel surfaces of paranthropines teeth are low, resembling those of H. habilis and clearly differing from those observed on H. ergaster, which display higher scratch densities indicative of the consumption of a wide assortment of highly abrasive foodstuffs. Buccal dental microwear patterns are consistent with those previously described for occlusal enamel surfaces, suggesting that Paranthropus consumed much softer diets than previously presumed and thus calling into question a strict interpretation of isotopic evidence. On the other hand, the significantly high buccal scratch densities observed in the H. ergaster specimens are not consistent with a highly specialized, mostly carnivorous diet; instead, they support the consumption of a wide range of highly abrasive food items.

show abstract

“…of human evolution (Schoenemann, 2006) imposed a substantially larger metabolic demand (Aiello and Wheeler, 1995; Leonard et al, 2007). A shift toward increased meat consumption may have contributed towards meeting that increased demand (Milton, 1999; Stanford, 1999; Stanford and Bunn, 2001; Ungar et al, 2006). Knowing that creatine is an abundant nutrient in red meat (Williams, 2007) and that phosphocreatine is critical to metabolically active cells (Wyss and Kaddurah-Daouk, 2000; Brosnan and Brosnan, 2007; Tachikawa et al, 2007), we hypothesized that a brain-specific increase in of phosphocreatine circuit gene expression arose in the lineage leading to humans.…”

Section: Discussionmentioning

confidence: 99%

“…Comparisons of both DNA sequence (Haygood et al, 2007) and mRNA abundance (Uddin et al, 2004; Khaitovich et al, 2006a; Blekhman et al, 2008; Babbitt et al, 2010) indicate that extensive changes in the regulation of metabolic associated genes help distinguish humans from chimpanzees. A dietary shift toward increased meat consumption by early hominids (Stanford, 1999; Stanford and Bunn, 2001; Ungar et al, 2006) may have contributed to some of the bioenergetic modifications necessary to support the human brain (Milton, 1987; Leonard and Robertson, 1992, 1994; Milton, 1999, 2003; Leonard et al, 2007). Comparative studies of primate genetics and molecular function provide powerful tools for identifying specific molecular changes associated with a human diet (Luca et al, 2010), an important step in understanding how changes in physiology allowed for the dramatic expansion of our brains.…”

Section: Introductionmentioning

confidence: 99%

Comparative expression analysis of the phosphocreatine circuit in extant primates: Implications for human brain evolution

Pfefferle

Warner

Wang

et al. 2011

Journal of Human Evolution

View full text Add to dashboard Cite

While the hominid fossil record clearly shows that brain size has rapidly expanded over the last ~2.5 M.yr., the forces driving this change remain unclear. One popular hypothesis proposes that metabolic adaptations in response to dietary shifts supported greater encephalization in humans. An increase in meat consumption distinguishes the human diet from that of other great apes. Creatine, an essential metabolite for energy homeostasis in muscle and brain tissue, is abundant in meat and was likely ingested in higher quantities during human origins. Five phosphocreatine circuit proteins help regulate creatine utilization within energy demanding cells. We compared the expression of all five phosphocreatine circuit genes in cerebral cortex, cerebellum, and skeletal muscle tissue for humans, chimpanzees, and rhesus macaques. Strikingly, SLC6A8 and CKB transcript levels are higher in the human brain, which should increase energy availability and turnover compared to non-human primates. Combined with other well-documented differences between humans and non-human primates, this allocation of energy to the cerebral cortex and cerebellum may be important in supporting the increased metabolic demands of the human brain.

show abstract

A hypothesis to explain the role of meat-eating in human evolution

Cited by 259 publications

References 58 publications

Identification of differences in human and great ape phytanic acid metabolism that could influence gene expression profiles and physiological functions

Identification of differences in human and great ape phytanic acid metabolism that could influence gene expression profiles and physiological functions

Testing Dietary Hypotheses of East African Hominines Using Buccal Dental Microwear Data

Comparative expression analysis of the phosphocreatine circuit in extant primates: Implications for human brain evolution

Contact Info

Product

Resources

About