187 research outputs found
Whatâs in a surname? Physique, aptitude, and sports type comparisons between Tailors and Smiths
Combined heredity of surnames and physique, coupled with past marriage patterns and trade-specific physical aptitude and selection factors, may have led to differential assortment of bodily characteristics among present-day men with specific trade-reflecting surnames (Tailor vs. Smith). Two studies reported here were partially consistent with this genetic-social hypothesis, first proposed by Bäumler (1980). Study 1 (N = 224) indicated significantly higher self-rated physical aptitude for prototypically strength-related activities (professions, sports, hobbies) in a random sample of Smiths. The counterpart effect (higher aptitude for dexterity-related activities among Tailors) was directionally correct, but not significant, and Tailor-Smith differences in basic physique variables were not significant. Study 2 examined two large datasets (Austria/Germany combined, and UK: N = 7001 and 20532) of menâs national high-score lists for track-and-field events requiring different physiques. In both datasets, proportions of Smiths significantly increased from light-stature over medium-stature to heavy-stature sports categories. The predicted counterpart effect (decreasing prevalences of Tailors along these categories) was not supported. Related prior findings, implicit egotism as an alternative interpretation of the evidence, and directions for further inquiry are discussed in conclusion
Twin Town in South Brazil: A Nazi's Experiment or a Genetic Founder Effect?
Cândido GodĂłi (CG) is a small municipality in South Brazil with approximately 6,000 inhabitants. It is known as the âTwins' Townâ due to its high rate of twin births. Recently it was claimed that such high frequency of twinning would be connected to experiments performed by the German Nazi doctor Joseph Mengele. It is known, however, that this town was founded by a small number of families and therefore a genetic founder effect may represent an alternatively explanation for the high twinning prevalence in CG. In this study, we tested specific predictions of the âNazi's experimentâ and of the âfounder effectâ hypotheses. We surveyed a total of 6,262 baptism records from 1959â2008 in CG catholic churches, and identified 91 twin pairs and one triplet. Contrary to the âNazi's experiment hypothesisâ, there is no spurt in twinning between the years (1964â1968) when Mengele allegedly was in CG (Pâ=â0.482). Moreover, there is no temporal trend for a declining rate of twinning since the 1960s (Pâ=â0.351), and no difference in twinning among CG districts considering two different periods: 1927â1958 and 1959â2008 (Pâ=â0.638). On the other hand, the âfounder effect hypothesisâ is supported by an isonymy analysis that shows that women who gave birth to twins have a higher inbreeding coefficient when compared to women who never had twins (0.0148, 0.0081, respectively, Pâ=â0.019). In summary, our results show no evidence for the âNazi's experiment hypothesisâ and strongly suggest that the âfounder effect hypothesisâ is a much more likely alternative for explaining the high prevalence of twinning in CG. If this hypothesis is correct, then this community represents a valuable population where genetic factors linked to twinning may be identified
The significance of nitrogen cost minimization in proteomes of marine microorganisms
Marine microorganisms thrive under low levels of nitrogen (N). N cost minimization is a major selective pressure imprinted on open-ocean microorganism genomes. Here we show that amino-acid sequences from the open ocean are reduced in N, but increased in average mass compared with coastal-ocean microorganisms. Nutrient limitation exerts significant pressure on organisms supporting the trade-off between N cost minimization and increased average mass of amino acids that is a function of increased A+T codon usage. N cost minimization, especially of highly expressed proteins, reduces the total cellular N budget by 2.7â10% this minimization in combination with reduction in genome size and cell size is an evolutionary adaptation to nutrient limitation. The biogeochemical and evolutionary precedent for these findings suggests that N limitation is a stronger selective force in the ocean than biosynthetic costs and is an important evolutionary strategy in resource-limited ecosystems
POSSIBLE IDENTITY OF TRANSCRIPTION AND TRANSLATION SIGNALS IN EARLY VITAL SYSTEMS
The distribution of codons was analysed in three classes of eukaryote proteins having widely different evolutionary rates: 78 histones, 40 tubulins, and seven fibrinogens. In this set of genes, (i) it was confirmed that codons which are components of known transcription signals, like ATA, are used infrequently when a synonym is available, particularly in the more constrained proteins, and (ii) it was observed that the three codons which have an iso-accepting transfer with anticodon UAA, UAG or UGA are also suppressed. Then, the distribution of UAA, UAG and UGA trimers was studied in 498 tDNAs and 198 rDNAs. It was found that these trimers are weakly but significantly suppressed in tDNAs and to a lesser extent in rDNAs. It was advanced that the present suppression of ATA, which codes for Methionine in several mitochondria, and of the TAA, TAG and TGA trimers in tDNAs, might be an indication that at the very early stages of the evolution of translation and transcription the signals for initiation and termination were shared by the two processes
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