chance events
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Author(s):  
Maarten J. Wensink ◽  
Alan A. Cohen

The classical evolutionary theories of aging suggest that aging evolves due to insufficient selective pressure against it. In these theories, declining selection pressure with age leads to aging through genes or resource allocations, implying that aging could potentially be stalled were genes, resource allocation, or selection pressure somewhat different. While these classical evolutionary theories are undeniably part of a description of the evolution of aging, they do not explain the diversity of aging patterns, and they do not constitute the only possible evolutionary explanation. Without denying selection pressure a role in the evolution of aging, we argue that the origin and diversity of aging should also be sought in the nature and evolution of organisms that are, from their very physiological make up, unmaintainable. Drawing on advances in developmental biology, genetics, biochemistry, and complex systems theory since the classical theories emerged, we propose a fresh evolutionary-mechanistic theory of aging, the Danaid theory. We argue that, in complex forms of life like humans, various restrictions on maintenance and repair may be inherent, and we show how such restrictions are laid out during development. We further argue that there is systematic variation in these constraints across taxa, and that this is a crucial factor determining variation in aging and lifespan across the tree of life. Accordingly, the core challenge for the field going forward is to map and understand the mosaic of constraints, trade-offs, chance events, and selective pressures that shape aging in diverse ways across diverse taxa.


2021 ◽  
pp. 99-118
Author(s):  
Franklin M. Harold

The story of life tells of relentless expansion from obscure beginnings to smother the earth in organized biochemistry. First came the prokaryotes, Bacteria and Archaea, followed some two billion years later by eukaryotic microbes. The latter pattern of organization underpins the rise of multicellular organisms, and their spectacular proliferation over the past 600 million years. There have been no fundamentally new kinds of organisms since, but the rise of mind culminating in humanity may signal a new phase in life’s history. Life has expanded in both quantity and quality, a gyre of mounting size, complexity, and functional capacity; in some elusive sense evolution is progressive. Multicellularity, the key invention, is not singular but happened multiple times in several eukaryotic lineages. The proliferation of higher organisms was probably enabled by increased energy flow, and dependent on the increase in atmospheric oxygen. It is studded with innovations in structure, physiology, and behavior, whose origin is a recurrent theme in evolutionary biology. Novelty is rooted in mutational events at the gene level, supplemented by the acquisition of genes from the outside by both gene transfer and symbiosis, and possibly by other avenues. Chance events were scrutinized and culled by natural selection. There appears to be no intrinsic progressive drive, but natural selection generally favors the more functional and better organized.


2021 ◽  
Author(s):  
Michael Tobler ◽  
Ryan Greenway ◽  
Joanna L Kelley

Convergent evolution, where independent lineages evolve similar traits when adapting to similar habitats, is a common phenomenon and testament to the repeatability of evolutionary processes. Still, non-convergence is also common, and a major question is whether apparently idiosyncratic, lineage-specific evolutionary changes are reflective of chance events inherent to evolutionary processes, or whether they are also influenced by deterministic genetic or ecological factors. To address this question, we quantified the degree of convergence in genome-wide patterns of gene expression across lineages of livebearing fishes (family Poeciliidae) that span 40 million years of evolution and have colonized extreme environments in the form of toxic, hydrogen-sulfide-rich springs. We specifically asked whether the degree of convergence across lineage pairs was related to their phylogenetic relatedness or the ecological similarity of the habitats they inhabit. Using phylogenetic comparative analyses, we showed that the degree of convergence was highly variable across lineage pairs residing in sulfide springs. While closely related lineages did not exhibit higher degrees of convergence than distantly related ones, we uncovered a strong relationship between degree of convergence and ecological similarity. Our results indicate that variation in the degree of convergence is not merely noise associated with evolutionary contingency. Rather, cryptic environmental variation that is frequently ignored when we employ reductionist approaches can significantly contribute to adaptive evolution. This study highlights the importance of multivariate approaches that capture the complexities of both selective regimes and organismal design when assessing the roles of determinism and contingency in evolution.


2021 ◽  
pp. 113-124
Author(s):  
Andrew C. A. Elliott

Who is the luckiest person in the world? What do we mean by ‘luck’? Luck is usually treated as something persistent, a quality that attaches to people, places or objects. We feel that luck should be balanced, that the wheel of fortune should always rotate to balance things out, but it doesn’t. Fate is a powerful and related idea that destiny pre-ordains the course of our lives. Fortune-telling techniques purport to get a glimpse of fate and to see hidden truths. Somewhat paradoxically, most kinds of divination make use of random methods. The paradox of fairness is explained. It seems, though, that what distinguishes self-described lucky people from those who consider themselves unlucky is a question of attitude, of how one interprets the chance events that have filled our lives.


Author(s):  
Ashish Karn ◽  
Brett Rosiejka ◽  
Pankaj Badoni ◽  
Raman Kumar Singh

The current paper explores the potential interlink between names of individuals in a society and its collective social consciousness, particularly with reference to the pervasive occurrence of the ‘mathematical names’ in the current Hindu society in the Indian subcontinent and beyond. Initially, an attempt is made to put things into mathematical perspective by drawing a quick sketch of some of the stellar achievements of the Indian mathematicians. Under the six broad categories of geometry, trigonometry, numeration, arithmetic, algebra, and mathematics in the Vedic tradition, a concise simple description of these subdivisions is presented, underlining the names of the concepts and terms, sometimes by producing the textual references. Then, upon identification of such mathematical terms, an attempt is made to juxtapose these with the names current in the Indian Hindu society. By employing an extensive dataset of university student names in India and the directories of Facebook and LinkedIn, we produce both qualitative and quantitative evidence of the presence of such names in the Indian subcontinent. Evidently, these names reflect the impressions of the tremendously rich mathematical heritage left by the Hindu stalwart mathematicians. This hypothesis has also been examined by taking surveys of people bearing these mathematical names, as well as by documenting the ‘conscious procedures’ that go behind the naming of a Hindu Indian child. In trying to investigate if such a phenomenon is unique to the Indian tradition, a stark contrast with the ‘names in mathematics’ as prevalent in the European mathematical traditions is presented, as cultural roots of mathematics are explored. Further, we ascribe the presence of these names as the extant remains of the colossal impact of multifarious mathematical traditions existing in India. Interestingly, the present research also brings to the fore, certain unseen facets of the Indian Hindu society as regards the education of mathematics to women – through an indirect exploration of their names. We also show that the pervasive occurrence of these names is not merely the result of semantic chance events, but denotes the richness of the Indian mathematical legacy. Next, we also present cross-cultural comparisons to show the uniqueness of Indian mathematical and scientific traditions that led to the pervasiveness of ‘mathematical names’ in India. Finally, an attempt is made to clarify some subtle points on the associations between mathematics and religion in India and other cultures of the world. It is sincerely hoped that the present study may shed light on the cultural roots of mathematics and may furnish a new dimension in the study of mathematics, culture and civilizations across the world.


Author(s):  
Ashish Karn ◽  
Brett Rosiejka ◽  
Pankaj Badoni ◽  
Raman Kumar Singh

The current paper explores the tenuous interlink between names of individuals in a society and its collective social consciousness, particularly with reference to the pervasive occurrence of the ‘mathematical names’ in the current Hindu society in the Indian subcontinent and beyond. Initially, an attempt is made to put things into mathematical perspective by drawing a quick sketch of the mathematical achievements of the Indian mathematicians. Then, under the six broad categories of geometry, trigonometry, numeration, arithmetic, algebra and mathematics in the Vedic tradition, a concise layman description of these subdivisions are presented, underlining the names of the concepts and terms, sometimes by producing the textual references. Next, upon identification of such mathematical terms, these names are juxtaposed with the names current in the Indian Hindu setting. By employing an extensive dataset of university student names in India and the databases of Facebook and LinkedIn, we produce both qualitative and quantitative evidence of the presence of such names in the Indian subcontinent. Evidently, these names reflect impressions of the rich mathematical heritage left by the Hindu stalwart mathematicians. This hypothesis has also been examined by taking surveys of people bearing these mathematical names, as well as by documenting the ‘conscious procedures’ that go behind the naming of a Hindu Indian child. In trying to investigate if such a phenomenon is unique to the Indian tradition, a stark contrast with the ‘names in mathematics’ as prevalent in the European mathematical traditions is presented, as cultural roots of mathematics are explored. Further, we ascribe the presence of these names as the extant remains of the colossal impact of multifarious mathematical traditions existing in India. In fact, the present research also brings to the fore, certain unseen facets of the Indian Hindu society as regards the education of mathematics to women – through an indirect exploration of their names. We then show that the pervasive occurrence of these names are not merely the result of semantic chance events, but denote the richness of the Indian mathematical legacy. We also present cross-cultural comparisons to show the uniqueness of Indian mathematical and scientific traditions that led to the pervasiveness of ‘mathematical names’ in India. Finally, an attempt is made to clarify some subtle points on the associations between mathematics and religion in India and other cultures of the world. It is a sincere hope that the present study may shed light on the cultural roots of mathematics and may provide a different dimension in the study of mathematics and society, across other civilizations.


2021 ◽  
Author(s):  
Ashish Karn ◽  
Brett Rosiejka ◽  
Pankaj Badoni ◽  
Raman Kumar Singh

The current paper explores the tenuous interlink between names of individuals in a society and its collective social consciousness, particularly with reference to the pervasive occurrence of the ‘mathematical names’ in the current Hindu society in the Indian subcontinent and beyond. Initially, an attempt is made to put things into mathematical perspective by drawing a quick sketch of the mathematical achievements of the Indian mathematicians. Then, under the six broad categories of geometry, trigonometry, numeration, arithmetic, algebra and mathematics in the Vedic tradition, a concise layman description of these subdivisions are presented, underlining the names of the concepts and terms, sometimes by producing the textual references. Next, upon identification of such mathematical terms, these names are juxtaposed with the names current in the Indian Hindu setting. By employing an extensive dataset of university student names in India and the databases of Facebook and LinkedIn, we produce both qualitative and quantitative evidence of the presence of such names in the Indian subcontinent. Evidently, these names reflect impressions of the rich mathematical heritage left by the Hindu stalwart mathematicians. This hypothesis has also been examined by taking surveys of people bearing these mathematical names, as well as by documenting the ‘conscious procedures’ that go behind the naming of a Hindu Indian child. In trying to investigate if such a phenomenon is unique to the Indian tradition, a stark contrast with the ‘names in mathematics’ as prevalent in the European mathematical traditions is presented, as cultural roots of mathematics are explored. Further, we ascribe the presence of these names as the extant remains of the colossal impact of multifarious mathematical traditions existing in India. In fact, the present research also brings to the fore, certain unseen facets of the Indian Hindu society as regards the education of mathematics to women – through an indirect exploration of their names. We then show that the pervasive occurrence of these names are not merely the result of semantic chance events, but denote the richness of the Indian mathematical legacy. We also present cross-cultural comparisons to show the uniqueness of Indian mathematical and scientific traditions that led to the pervasiveness of ‘mathematical names’ in India. Finally, an attempt is made to clarify some subtle points on the associations between mathematics and religion in India and other cultures of the world. It is a sincere hope that the present study may shed light on the cultural roots of mathematics and may provide a different dimension in the study of mathematics and society, across other civilizations.


Author(s):  
Pieter E. Baay ◽  
Christopher M. Napolitano ◽  
Mattijs C. Schipper

Evidence suggests that chance plays an important role in careers. Instead of describing such events through “sheer luck,” the authors propose in this theoretical and empirical chapter that opportunity and preparation helps explain the occurrence, perception, and selection of chance events. Study 1 used longitudinal data on 390 emerging adults who reported the occurrence of chance events in their school-to-work transition. Supporting the hypotheses, participants who had prepared better for the school-to-work transition and had better opportunities (in terms of their social network) experienced more chance events. Study 2 examined the perception and selection of chance events in a lab setting. Sixty-seven emerging adult applicants for an actual position were exposed to the same chance events. Consistent with hypotheses, better prepared job applicants were more likely to select these events. Instead of sheer luck, the authors suggest that job seekers can create serendipity by capitalizing on chance events.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Dariusz Piwczyński ◽  
Beata Sitkowska ◽  
Marcin Brzozowski ◽  
Mariusz Bogucki ◽  
Piotr Wójcik

Abstract The main objective of the study was to determine the effect of transition from a conventional milking system (CMS) to an automatic milking system (AMS) on survival of 6361 Polish Holstein-Friesian cows to second (SL2), third (SL3) and fourth (SL4) lactation as well culling reasons. The cows were born between 2002 and 2015 and calved between 2004 and 2018. All data for the survival analysis and culling reasons of cows in 17 herds during operation of CMS and AMS were extracted from the SYMLEK official milk recording system. Cow survival (SL2, SL3 and SL4) was analysed with multiple logistic regression using the following effects in the model: milking system (MS), first calving season (CS), age at first calving (AFC), ease of first calving (CE), birth of a dead calf at first calving (DC), milk yield (MY) for full first lactation (MY – this effect was ignored in SL2 analysis), herd (H), and MS × H interaction. In the next stage of the study, χ2 test was used to analyse culling reasons of cows (udder diseases, low fertility (infertility and reproductive disorders), locomotor diseases, low milk yield, other diseases (metabolic, digestive and respiratory diseases), accidents and chance events) in the first, second and third lactation and collectively in the first three lactations. Logistic regression analysis indicated a significant effect of MS, AFC, DC on SL2 and SL3, and of MY on SL3 and SL4. Moreover, H and MS × H interaction had a highly significant effect on SL2, SL3, and SL4. Cows used in AMS barns were characterized by significantly worse SL2 and SL3 compared to CMS (odds ratio), by 27.8% and 31.0%, respectively. It was also observed that the effect of switching from CMS to AMS on cow survival was determined by herd membership – in most herds this effect was unfavourable. A distinctly positive effect of milking automation on cow survival (SL2, SL3, SL4) was noted in only one barn (herd) – it was a new barn with a considerably expanded number of milked cows, where the lying area was covered with straw. When analysing the reasons for culling in the first three lactations collectively, it was found that after the AMS system was introduced into the herds, there were increases in the rate of culling for locomotor diseases (by 0.85 percentage points (p.p.)), low milk yield (1.36 p.p.) and other diseases (3.01 p.p.). It was also observed that the automation of milking reduced culling due to udder diseases by 0.37 p.p., low fertility by 3.24 p.p., and accidents and chance events by 1.60 p.p.


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