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W Schiefenhövel

Publications and source records attributed to W Schiefenhövel.

10 recordsLinked to original sources

Independent histories of human Y chromosomes from Melanesia and Australia.

To investigate the origins and relationships of Australian and Melanesian populations, 611 males from 18 populations from Australia, Melanesia, and eastern/southeastern Asia were typed for eight single-nucleotide polymorphism (SNP) loci and seven short tandem-repeat loci on the Y chromosome. A unique haplotype, DYS390.1del/RPS4Y711T, was found at a frequency of 53%-69% in Australian populations, whereas the major haplotypes found in Melanesian populations (M4G/M5T/M9G and DYS390.3del/RPS4Y711T) are absent from the Australian populations. The Y-chromosome data thus indicate independent histories for Australians and Melanesians, a finding that is in agreement with evidence from mtDNA but that contradicts some analyses of autosomal loci, which show a close relationship between Australian and Melanesian (specifically, highland Papua New Guinean) populations. Since the Australian and New Guinean landmasses were connected when first colonized by humans > or =50,000 years ago but separated some 8,000 years ago, a possible way to reconcile all the genetic data is to infer that the Y-chromosome and mtDNA results reflect the past 8,000 years of independent history for Australia and New Guinea, whereas the autosomal loci reflect the long preceding period of common origin and shared history. Two Y-chromosome haplotypes (M119C/M9G and M122C/M9G) that originated in eastern/southeastern Asia are present in coastal and island Melanesia but are rare or absent in both Australia and highland Papua New Guinea. This distribution, along with demographic analyses indicating that population expansions for both haplotypes began approximately 4,000-6,000 years ago, suggests that these haplotypes were brought to Melanesia by the Austronesian expansion. Most of the populations in this study were previously typed for mtDNA SNPs; population differentiation is greater for the Y chromosome than for mtDNA and is significantly correlated with geographic distance, a finding in agreement with results of similar analyses of European populations.

Asia, Southeastern↗

Melanesian origin of Polynesian Y chromosomes.

BACKGROUND: Two competing hypotheses for the origins of Polynesians are the 'express-train' model, which supposes a recent and rapid expansion of Polynesian ancestors from Asia/Taiwan via coastal and island Melanesia, and the 'entangled-bank' model, which supposes a long history of cultural and genetic interactions among Southeast Asians, Melanesians and Polynesians. Most genetic data, especially analyses of mitochondrial DNA (mtDNA) variation, support the express-train model, as does linguistic and archaeological evidence. Here, we used Y-chromosome polymorphisms to investigate the origins of Polynesians. RESULTS: We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. CONCLUSIONS: All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the 'slow-boat' model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.

Asia↗

[Suffering without meaning? Illness, pain and death. Development of evolutionary medicine].

The human species is an optimized product of evolution. This realization and knowledge of the highly sensitive and sensible biocybernetical processes in our bodies is now largely out of sight in modern medicine. To develop an evolutionary and cross-cultural perspective of human life and its biological, psychic and social conditions is therefore particularly important for the health sciences. Birth behaviour, intensive care for premature babies, post-partum dysphoria, sudden infant death, hip dysplasia, cry babies, eating disorders, stress-induced diseases, depression, ageing and dying serve as examples to sketch this new approach. It may probably facilitate diagnostic and therapeutic schemes which will be better adapted to human needs and capacities and can, therefore, be more successful than the ones in the past.

Adult↗

Evidence for mitochondrial DNA recombination in a human population of island Melanesia.

Mitochondrial DNA (mtDNA) analysis has proved useful in studies of recent human evolution and the genetic affinities of human groups of different geographical regions. As part of an extensive survey of mtDNA diversity in present-day Pacific populations, we obtained sequence information of the hypervariable mtDNA control region of 452 individuals from various localities in the western Pacific. The mtDNA types fell into three major groups which reflect the settlement history of the area. Interestingly, we detected an extremely rare point mutation at high frequency in the small island of Nguna in the Melanesian archipelago of Vanuatu. Phylogenetic analysis of the mtDNA data indicated that the mutation was present in individuals of separate mtDNA lineages. We propose that the multiple occurrence of a rare mutation event in one isolated locality is highly improbable, and that recombination between different mtDNA types is a more likely explanation for our observation. If correct, this conclusion has important implications for the use of mtDNA in phylogenetic and evolutionary studies.

Biological Evolution↗

Molecular genetic evidence for the human settlement of the Pacific: analysis of mitochondrial DNA, Y chromosome and HLA markers.

Present-day Pacific islanders are thought to be the descendants of Neolithic agriculturalists who expanded from island South-east Asia several thousand years ago. They speak languages belonging to the Austronesian language family, spoken today in an area spanning half of the circumference of the world, from Madagascar to Easter Island, and from Taiwan to New Zealand. To investigate the genetic affinities of the Austronesian-speaking peoples, we analysed mitochondrial DNA, HLA and Y-chromosome polymorphisms in individuals from eight geographical locations in Asia and the Pacific (China, Taiwan, Java, New Guinea highlands, New Guinea coast, Trobriand Islands, New Britain and Western Samoa). Our results show that the demographic expansion of the Austronesians has left a genetic footprint. However, there is no simple correlation between languages and genes in the Pacific.

Base Sequence↗

Towards understanding the origin and dispersal of Austronesians in the Solomon Sea: HLA class II polymorphism in eight distinct populations of Asia-Oceania.

HLA class II nucleotide sequence polymorphisms were examined in eight ethnic groups of Asia-Oceania using DNA typing methods. Allele frequencies and characteristic DR/DQ haplotypes were determined and compared with those of other populations of Asia-Oceania. Genetic distances were measured to show the genetic relationship within the studied populations as well as between the studied populations and previously published populations. Phylogenetic trees were constructed based on HLA allele frequencies using the neighbour-joining method. The populations, mainly Trobriand Islanders, Roro, Tolai, Western Samoans and Taiwanese Aborigines, are characterized by a reduced diversity at the HLA loci examined, especially for DPB1. The high frequency of the 'Asian'-specific DPB1*0501 allele in Trobrianders and Roro, but also in Western Samoans and Taiwanese Aborigines, was the most striking result. The prevalence of DPB1*0501 and the short genetic distance from Trobriander and Roro to Taiwanese Aborigines provide evidence that the origin of the Austronesian odyssey is south-east Asia, and Taiwan could be an important part of it. The relatedness of Trobrianders to the Polynesian population from Western Samoa indicates a probable recent common ancestor. The observed lack of diversity may reflect bottleneck(s) and/or limited diversity of the founding population. Analysis of HLA class I antigens, together with mt-DNA and Y-chromosomal studies, will give us further information about the settlement of the Trobriand and other islands during the colonization of the Pacific.

Alleles↗

Genetic relationships of Asians and Northern Europeans, revealed by Y-chromosomal DNA analysis.

We have identified a new T-->C transition on the human Y chromosome. C-allele chromosomes have been found only in a subset of the populations from Asia and northern Europe and reach their highest frequencies in Yakut, Buryats, and Finns. Examination of the microsatellite haplotypes of the C-allele chromosomes suggests that the mutation occurred recently in Asia. The Y chromosome thus provides both information about population relationships in Asia and evidence for a substantial paternal genetic contribution of Asians to northern European populations such as the Finns.

Animals↗

Perception, expression, and social function of pain: a human ethological view.

Pain has important biomedical, socioanthropological, semiotic, and other facets. In this contribution pain and the expression of pain are looked at from the perspective of evolutionary biology, utilizing, among others, cross-cultural data from field work in Melanesia. No other being cares for sick and suffering conspecifics in the way humans do. Notwithstanding aggression and neglect, common in all cultures, human societies can be characterized as empathic, comforting, and promoting the health and sell-being of their members. One important stimulus triggering this caring response in others is the expression of pain. The nonverbal channel of communication, particularly certain universal--i.e., culture-independent facial expressions, gestures, and body postures, convey much of the message from the pain-stricken person to the group. These behaviors signal the person's physical and psychical pain, sadness, grief, and despair in ways very similar to the signs given by infants and small children: the body loses tonus and sinks or drops to the ground, the gestures are those of helplessness. Pain and grief may be so strong that control is lost not only over the body's posture but also over the mind's awareness. In such cases the afflicted person may carry out actions endangering himself or others. In general, these behavior patterns resemble those of infants in situations of distress and danger, and it is not surprising that the response of the members of the group is basically parental: taking care, assisting and consoling. Perceptive and behavioral patterns which developed in the course of avian and mammalian phylogeny to serve the well-being of the young have proven, as was shown by Eibl-Eibesfeldt (1989), to be powerful building blocks for actions in other spheres of human interaction. Love is one such field, the reactions to a conspecific suffering pain is another.

Animals↗

[Parent-child interaction during activity and rest behavior of inhabitants of Trobriand Islands (Papua New Guinea)].

Sleep/activity patterns were continuously registered using microelectronic actometers on inhabitants of Tauwema (Papua New Guinea) who represent a traditionally living society. Results of analysis of parent-infant interactions of 4 families with infants of 1, 2, 5, and 11 months of age are presented. Results of power spectral analysis suggest that time patterns of mother-infant interactions are changing with the infants AE age. Consequences of this developmental process are discussed.

Adolescent↗