Hunter-gatherer human nature and health system safety: an evolutionary cleft stick?
(17/209)
The stunning archaeological find of a new species of human dubbed the hobbit, formally named Homo floresiensis, is a reminder that humans and hobbits are evolved for transient lives, subsisting in an environment radically different from that of contemporary societies. Although the problems facing health systems are well documented, few scholars have taken an evolutionary-level approach to understanding them. By considering the nature of humans as adapted not for modern societies but for hunter-gatherer existence, and examining what humans were evolved for, new light can be shed on contemporary behaviours exposed by the medical inquiries into what is going wrong in acute health systems. Investigation of two of these inquiries shows how health professionals under pressure typically default to tribal behaviours, have recourse to hierarchies and engage in turf protection routines. Those who have conducted studies into iatrogenic harm or presided over the medical inquiries have argued that culture change is the solution to health care's ills. This is likely to be much harder to institute than some people realize, especially given our underlying hunter-gatherer nature. This is an evolutionary cleft stick that has not been factored in by those optimistic about health sector reform. The implications are that we need a deep understanding of human nature in addressing health system problems and to recognize that profound culture change is more challenging than many believe. Paradoxically, it is when humans are faced with seemingly intractable problems that a collective way forward might emerge. (+info)
Neighbour-nets portray the Chinese dialect continuum and the linguistic legacy of China's demic history.
(18/209)
As with species studied by evolutionary biologists, languages are evolving entities. They can evolve in tree-like patterns, possibly blurred by borrowing, but they can also develop in non-tree-like schemes. For instance, diglossia, as in the case of Chinese, can counterbalance the hierarchical pattern expected from differentiation by internal change associated with isolation by distance of speech communities. Using two lexical datasets, either the basic lexicon supposedly more immune to borrowing or a representative sample of the whole lexicon, we investigate the development pattern of Chinese dialects using a neighbour-net approach, which is an unprejudiced technique for representing object relationships. The resulting graphs are consistent with a dialect continuum shaped by counterbalanced effects of homogenizing diglossia and borrowing versus differentiating spread of speech communities. Historical events and linguistic claims can be mapped on these graphs. (+info)
Structural phylogenetics and the reconstruction of ancient language history.
(19/209)
The contribution of language history to the study of the early dispersals of modern humans throughout the Old World has been limited by the shallow time depth (about 8000 +/- 2000 years) of current linguistic methods. Here it is shown that the application of biological cladistic methods, not to vocabulary (as has been previously tried) but to language structure (sound systems and grammar), may extend the time depths at which language data can be used. The method was tested against well-understood families of Oceanic Austronesian languages, then applied to the Papuan languages of Island Melanesia, a group of hitherto unrelatable isolates. Papuan languages show an archipelago-based phylogenetic signal that is consistent with the current geographical distribution of languages. The most plausible hypothesis to explain this result is the divergence of the Papuan languages from a common ancestral stock, as part of late Pleistocene dispersals. (+info)
Ancient DNA from the first European farmers in 7500-year-old Neolithic sites.
(20/209)
The ancestry of modern Europeans is a subject of debate among geneticists, archaeologists, and anthropologists. A crucial question is the extent to which Europeans are descended from the first European farmers in the Neolithic Age 7500 years ago or from Paleolithic hunter-gatherers who were present in Europe since 40,000 years ago. Here we present an analysis of ancient DNA from early European farmers. We successfully extracted and sequenced intact stretches of maternally inherited mitochondrial DNA (mtDNA) from 24 out of 57 Neolithic skeletons from various locations in Germany, Austria, and Hungary. We found that 25% of the Neolithic farmers had one characteristic mtDNA type and that this type formerly was widespread among Neolithic farmers in Central Europe. Europeans today have a 150-times lower frequency (0.2%) of this mtDNA type, revealing that these first Neolithic farmers did not have a strong genetic influence on modern European female lineages. Our finding lends weight to a proposed Paleolithic ancestry for modern Europeans. (+info)
The competitive advantage of sanctioning institutions.
(21/209)
Understanding the fundamental patterns and determinants of human cooperation and the maintenance of social order in human societies is a challenge across disciplines. The existing empirical evidence for the higher levels of cooperation when altruistic punishment is present versus when it is absent systematically ignores the institutional competition inherent in human societies. Whether punishment would be deliberately adopted and would similarly enhance cooperation when directly competing with nonpunishment institutions is highly controversial in light of recent findings on the detrimental effects of punishment. We show experimentally that a sanctioning institution is the undisputed winner in a competition with a sanction-free institution. Despite initial aversion, the entire population migrates successively to the sanctioning institution and strongly cooperates, whereas the sanction-free society becomes fully depopulated. The findings demonstrate the competitive advantage of sanctioning institutions and exemplify the emergence and manifestation of social order driven by institutional selection. (+info)
Why is stress so deadly? An evolutionary perspective.
(22/209)
The reaction of the body to prolonged stress has many harmful effects. Classical theory assumes that stress responses have evolved due to their short-term selective advantages ('flight or fight'), and despite their adverse long-term effects. In contrast, we demonstrate that the adverse effects of stress responses may have a selective advantage. Using an analytical model we show that a gene that causes the early death of a relatively unfit individual can increase in frequency in a structured population even if it has no positive effect on that individual. This result offers a new perspective on the relations between stress factors, stress responses and stress-related diseases. (+info)
Costly punishment across human societies.
(23/209)
Recent behavioral experiments aimed at understanding the evolutionary foundations of human cooperation have suggested that a willingness to engage in costly punishment, even in one-shot situations, may be part of human psychology and a key element in understanding our sociality. However, because most experiments have been confined to students in industrialized societies, generalizations of these insights to the species have necessarily been tentative. Here, experimental results from 15 diverse populations show that (i) all populations demonstrate some willingness to administer costly punishment as unequal behavior increases, (ii) the magnitude of this punishment varies substantially across populations, and (iii) costly punishment positively covaries with altruistic behavior across populations. These findings are consistent with models of the gene-culture coevolution of human altruism and further sharpen what any theory of human cooperation needs to explain. (+info)
Climate-controlled Holocene occupation in the Sahara: motor of Africa's evolution.
(24/209)
Radiocarbon data from 150 archaeological excavations in the now hyper-arid Eastern Sahara of Egypt, Sudan, Libya, and Chad reveal close links between climatic variations and prehistoric occupation during the past 12,000 years. Synoptic multiple-indicator views for major time slices demonstrate the transition from initial settlement after the sudden onset of humid conditions at 8500 B.C.E. to the exodus resulting from gradual desiccation since 5300 B.C.E. Southward shifting of the desert margin helped trigger the emergence of pharaonic civilization along the Nile, influenced the spread of pastoralism throughout the continent, and affects sub-Saharan Africa to the present day. (+info)