Objectives

Traditional interpretation of Fisher's Fundamental Theorem of Natural Selection is that life history traits (LHT), which are closely related with fitness, show lower heritabilities, whereas morphological traits (MT) are less related with fitness and they are expected to show higher heritabilities. In humans, although few studies have examined the heritability of LHT and MT, none of them have analyzed the same sample for comparative purposes. Here we assessed, for the first time, the heritability, additive genetic variance (V_A), residual variance (V_R) and coefficient of genetic additive variation (CV_A) values of LHT and MT in a singular collection of identified skulls with associated demographic records from Hallstatt (Austria).

Materials and Methods

LHT, such as lifespan, number of offspring, age at birth of first and last child, reproductive span, and lifetime reproductive success, were estimated from 18,134 individuals from the Hallstatt Catholic parish records, which represent seven generations and correspond to a time span of 400 years. MT were assessed through 17 craniofacial indices and 7 angles obtained from 355 adult crania from the same population. Heritability, V_A, V_R, and CV_A values of LHT and MT were calculated using restricted maximum likelihood methods.

Results

LHT heritabilities ranged from 2.3 to 34% for the whole sample, with men showing higher heritabilities (4–45%) than women (0-23.7%). Overall, MT presented higher heritability values than most of LHT, ranging from 0 to 40.5% in craniofacial indices, and from 13.8 to 32.4% in craniofacial angles. LHT showed considerable additive genetic variance values, similar to MT, but also high environmental variance values, and most of them presenting a higher evolutionary potential than MT.

Discussion

Our results demonstrate that, with the exception of lifespan, LHT show lower heritability values, than MT. The lower heritability of LHT is explained by a higher influence of environmental and cultural factors.

Catholicism and Protestantism have different ways of promoting the family unit that could influence survival and fertility at a population level. Parish records in the Austrian village of Hallstatt allowed the reconstruction of Catholic and Protestant genealogies over a period of 175 years (1733-1908) to evaluate how religion and social changes affected reproduction and survival. Life history traits such as lifespan beyond 15 years, number of offspring, reproductive span, children born out of wedlock and child mortality were estimated in 5678 Catholic and 3282 Protestant individuals. The interaction of sex, time and religion was checked through non-parametric factorial ANOVAs. Religion and time showed statistically significant interactions with lifespan >15 years, number of offspring and age at birth of first child. Protestants lived longer, had a larger reproductive span and an earlier age at birth of first child. Before the famine crisis of 1845-1850, Protestants showed lower values of childhood mortality than Catholics. Comparison of the number of children born out of wedlock revealed small differences between the two religions. Religion influenced reproduction and survival, as significant differences were found between Catholics and Protestants. This influence could be explained in part by differential socioeconomic characteristics, since Protestants may have enjoyed better living and sanitary conditions in Hallstatt.

Shifts in social structure and cultural practices can potentially promote unusual combinations of allele frequencies that drive the evolution of genetic and phenotypic novelties during human evolution. These cultural practices act in combination with geographical and linguistic barriers and can promote faster evolutionary changes shaped by gene-culture interactions. However, specific cases indicative of this interaction are scarce. Here we show that quantitative genetic parameters obtained from cephalometric data taken on 1,203 individuals analyzed in combination with genetic, climatic, social, and life-history data belonging to six South Amerindian populations are compatible with a scenario of rapid genetic and phenotypic evolution, probably mediated by cultural shifts. We found that the Xavante experienced a remarkable pace of evolution: the rate of morphological change is far greater than expected for its time of split from their sister group, the Kayapo, which occurred around 1,500 y ago. We also suggest that this rapid differentiation was possible because of strong social-organization differences. Our results demonstrate how human groups deriving from a recent common ancestor can experience variable paces of phenotypic divergence, probably as a response to different cultural or social determinants. We suggest that assembling composite databases involving cultural and biological data will be of key importance to unravel cases of evolution modulated by the cultural environment.

Quantitative craniometrical traits have been successfully incorporated into population genetic methods to provide insight into human population structure. However, little is known about the degree of genetic and non-genetic influences on the phenotypic expression of functionally based traits. Many studies have assessed the heritability of craniofacial traits, but complex patterns of correlation among traits have been disregarded. This is a pitfall as the human skull is strongly integrated. Here we reconsider the evolutionary potential of craniometric traits by assessing their heritability values as well as their patterns of genetic and phenotypic correlation using a large pedigree-structured skull series from Hallstatt (Austria). The sample includes 355 complete adult skulls that have been analysed using 3D geometric morphometric techniques. Heritability estimates for 58 cranial linear distances were computed using maximum likelihood methods. These distances were assigned to the main functional and developmental regions of the skull. Results showed that the human skull has substantial amounts of genetic variation, and a t-test showed that there are no statistically significant differences among the heritabilities of facial, neurocranial and basal dimensions. However, skull evolvability is limited by complex patterns of genetic correlation. Phenotypic and genetic patterns of correlation are consistent but do not support traditional hypotheses of integration of the human shape, showing that the classification between brachy- and dolicephalic skulls is not grounded on the genetic level. Here we support previous findings in the mouse cranium and provide empirical evidence that covariation between the maximum widths of the main developmental regions of the skull is the dominant factor of integration in the human skull.

It has long been unclear whether the different derived cranial traits of modern humans evolved independently in response to separate selection pressures or whether they resulted from the inherent morphological integration throughout the skull. In a novel approach to this issue, we combine evolutionary quantitative genetics and geometric morphometrics to analyze genetic and phenotypic integration in human skull shape. We measured human skulls in the ossuary of Hallstatt (Austria), which offer a unique opportunity because they are associated with genealogical data. Our results indicate pronounced covariation of traits throughout the skull. Separate simulations of selection for localized shape changes corresponding to some of the principal derived characters of modern human skulls produced outcomes that were similar to each other and involved a joint response in all of these traits. The data for both genetic and phenotypic shape variation were not consistent with the hypothesis that the face, cranial base, and cranial vault are completely independent modules but relatively strongly integrated structures. These results indicate pervasive integration in the human skull and suggest a reinterpretation of the selective scenario for human evolution where the origin of any one of the derived characters may have facilitated the evolution of the others.

The human skull is a complex and highly integrated structure that has long held the fascination of anthropologists and evolutionary biologists. Recent studies of the genetics of craniofacial variation reveal a very complex and multifactorial picture. These findings contrast with older ideas that posit much simpler developmental bases for variation in cranial morphology such as the growth of the brain or the growth of the chondrocranium relative to the dermatocranium. Such processes have been shown to have major effects on cranial morphology in mice. It is not known, however, whether they are relevant to explaining normal phenotypic variation in humans. To answer this question, we obtained vectors of shape change from mutant mouse models in which the developmental basis for the craniofacial phenotype is known to varying degrees, and compared these to a homologous dataset constructed from human crania obtained from a single population with a known genealogy. Our results show that the shape vectors associated with perturbations to chondrocranial growth, brain growth, and body size in mice do largely correspond to axes of covariation in humans. This finding supports the view that the developmental basis for craniofacial variation funnels down to a relatively small number of key developmental processes that are similar across mice and humans. Understanding these processes and how they influence craniofacial shape provides fundamental insights into the developmental basis for evolutionary change in the human skull as well as the developmental-genetic basis for normal phenotypic variation in craniofacial form.

Nya undersökningar visar att Ötzi blev förföljd och skjuten med ett pilskott. Kopior av hans utrustning visas på Öland i sommar.

Det är nu mer än femton år sedan Ötzi, eller Ismannen, som han också kallas, upptäcktes i Alperna. Aldrig tidigare hade en mumie av en cirka 5300 år gammal, välbevarad stenåldersmänniska, påträffats med full utrustning. Kläder och organiska delar av utrustningen hade bevarats; trä, näver, skinn och botaniska rester, gräs från en gräskappa och från en knivslida och olika tvinnade rep, snören och nät, hö från isolering av skorna, och även enstaka lönnblad som använts för bevaring av glöd i en transportbehållare av näver. Till och med befjädringen av två pilar hade bevarats, lindade till pilskaften med nässeltråd. Med ens hade arkeologerna fått facit till många frågor vars svar man tidigare enbart kunnat spekulera i.

Idag vilar Ötzi i ett tidigare bankpalats i italienska Bolzano, provinshuvudstad i Sydtyrolen, byggt under den österrikisk-ungerska monarkins tid. I dess nya arkeologiska museum kan Ötzi beskådas genom ett glasfönster, och hans unika utrustning är utställd.

Det började tidigt gå rykten om att fyndet skulle vara en förfalskning. Det gick så långt att det till och med publicerades en bok om ”förfalskningen”, skriven...

In artiodactyles and perissodactyles the interior of the costal cartilages ossify, forming a spongy, osseous tissue. Recently, it has been discovered that such ossifications frequently display visible lines perpendicular to the cur-vature of the ossification. Such lines are not rare, and often several lines along the same costal cartilage are observed. Macerated ossified costal cartilages frequently, but not always, split into short, bony stabs with straight, cutoff ends, sometimes retaining organic matter encircled within a bony periphery. In archaeological materials such bony stabs areoccasionally observed, and are just denoted “costal cartilages” if recognized. The cause of these structures is not clear. Some may be regarded as transverse splits of the ossifications along a weakness zone, but in other cases the cause isobviously a fracture with more or less extensive callus formation. The smooth surfaces are typical and cannot be con-fused with a secondary fracture, which occur after deposition or maceration. The smooth ends of a healed fracture al-ways display a thin layer of compact tissue, while a secondary fracture is irregular and displays the spongy tissue. Thus, they may be considered as healed micro or macro fractures, where fusion of the fractured ends had occurred along theperiphery of the ossification. In other cases, however, healing may involve dislocation prior to the healing process, ex-tensive callus formation, lipping or formation of pseudoarthroses. How such an injury affected the animal is not gener-ally known. However, in the cases of dislocation and extensive bony reaction to the fracture, it is highly probable that the wellbeing of the animal was influenced by the injury.

Domestication of animals and plants marked a turning point in human prehistory. To date archaeology, archaeozoology and genetics have shed light on when and where all of our major livestock species were domesticated. Phenotypic changes associated with domestication have occurred in all farm animals. Coat colour is one of the traits that have been subjected to the strongest human selection throughout history. Here we use genotyping of coat colour SNPs in horses to investigate whether there were any regional differences or preferences for specific colours associated with specific cultural traditions in Iron Age Sweden. We do this by identifying the sex and coat colour of horses sacrificed at Skedemosse, Oland (Sweden) during the Iron Age, as well as in horses from two sites in Uppland, Ultuna and Valsgarde (dated to late Iron Age). We show that bay, black and chestnut colours were all common and two horses with tobiano spotting were found. We also show how the combination of sex identification with genotyping of just a few SNPs underlying the basic coat colours can be used to identify the minimum number of individuals at a site on a higher level than morphological methods alone. Although separated by 500 km and from significantly different archaeological contexts the horses at Skedemosse and Ultuna are quite homogenous when it comes to coat colour phenotypes, indicating that there were no clear geographical variation in coat colouration in Sweden during the late Iron Age and early Viking Age.

Knowledge of subpopulation identity including substructure is a prerequisite for sound management of polar bears (Ursus maritimus). It is not known whether the present catch of polar bears in the East Greenland subpopulation (EG) is sustainable. We used the Mean Measure of Divergence (MMD) to examine geographical variation in non-metrical traits from 1414 polar bear (Ursus maritimus) skulls collected in East Greenland (EG), Svalbard (SVA), Franz Josef Land (FJL), Davis Strait (DS), Baffin Bay (BB), and Kane Basin (KB), between 1830 and 2013. We focused on East Greenland with the goal of examining substructuring in the subpopulation. We did not find significant differences among samples across four areas of the EG subpopulation (i.e., offshore Fram Strait, NE, SE, and SW Greenland) using data from 1830 to 1983. Our analyses did not lend support to substructuring. However, we draw our conclusions with caution because skulls were sampled over a long time period and had low power due to small sample sizes. Also, comparisons were limited to pre-1980s skulls. The decrease in sea ice in EG since the 1990s due to climate change may have led to substructuring not detected with MMD. This study contributes to the current efforts by Greenland authorities to quantify connectivity of polar bears between southeast and northeast Greenland which is important information for the evaluation of the sustainability of the catch of bears from the EG subpopulation.