Similar features show up in evolutionary-unrelated groups. What does this mean?Stephen Jay Gould famously asked what what happen in evolution if one could “replay the tape of life” and start over. Would humans result, or would the products of natural selection be unrecognizable? Gould strongly defended the latter position. He even doubted that intelligence or consciousness would emerge. This view is called contingency: so many unpredictable factors influence the direction of evolution, it is impossible to predict what would happen. Supporters of contingency can find plenty of examples of highly divergent organisms evolving in the same environment.Other evolutionists disagree that natural selection is governed completely by chance. They think that the environment channels mutation and selection toward particular outcomes. While the details might differ, the forms of organisms would be constrained by environmental factors. This view is called determinism; it lends a certain degree of predictability to evolution. One of its defenders is paleontologist Simon Conway Morris, who can draw on a multitude of examples of convergent evolution, some of them quite remarkable. A recent paper in PNAS, for instance, argues that similar structures have arisen independently three times in fungus-farming ants. It seems to these evolutionists that the environment somehow channels natural selection toward similar designs or solutions to problems (but see 3 Oct 2015).In its extreme form, the anti-contingency view is called structuralism. Proposed by D’Arcy Thompson, author of the influential book On Growth and Form, this view suggests that properties of the universe drive biology toward particular kinds of organisms. Michael Denton, who defends this view in Evolution: Still a Theory in Crisis (2016), points out numerous examples of patterns in nature that persist despite being non-adaptive. Even though he believes in universal common descent, Denton argues that the patterns defy natural selection. Extreme structuralism borders on Platonism: the idea that particular organisms are reflections of ideal forms beyond our experience. Theistic evolutionists might be attracted to this view.These differing views boil down to the role of chance in biological evolution. A new article from Washington University in St. Louis (WUSTL), “Replaying the tape of life: Is it possible?” weighs in on this debate.How predictable is evolution? The answer long has been debated by biologists grappling with the extent to which history affects the repeatability of evolution.A review published in the Nov. 9 issue of Science explores the complexity of evolution’s predictability in extraordinary detail. In it, researchers from Kenyon College, Michigan State University and Washington University in St. Louis closely examine evidence from a number of empirical studies of evolutionary repeatability and contingency in an effort to fully interrogate ideas about contingency’s role in evolution.The paper in Science was co-authored by Zachary Blount, Richard Lenski and Jonathan Losos. Lenski has run the longest biological experiment on evolution, called the Long-Term Evolution Experiment (LTEE). For 30 years, he has transferred test tubes of E. coli to new cultures over 65,000 generations to see what evolution comes up with. Ever since Gould wrote his thought experiment on “replaying the tape of life” in his 1989 book about the Burgess Shale, Wonderful Life, other attempts have been made to determine the role of contingency in evolution. What is the thinking of current Darwinians, almost 30 years since Gould?In WUSTL’s press release, Blount wrongly ascribes directionality to natural selection:“How history plays out isn’t really predictable. Historical outcomes are contingent on long chains of events loaded with tiny little details,” said Zachary Blount, senior research associate at Michigan State and a visiting assistant professor of biology at Kenyon, and lead author of the review. “Unlike history, though, evolution has the deterministic force of natural selection, but that determinism is always in tension with the chanciness. How does that tension affect what evolves? Which is more important: contingency on details of history, or determinism?”The statement errs on two points: natural selection is not a force, and it is not deterministic: otherwise, all organisms in the same environment would end up the same. A third problem, even more severe, is that natural selection has never been observed to create a new, functional, complex organ or system. It cannot operate on anything until it’s already there. It has no creative power; it is passive; and it is utterly blind and aimless, caring nothing what what heppens.At the end of the paper, though, the authors cannot decide which view, determinism or contingency, is more important:Where to now? Clearly, evolution can be both contingent and deterministic, and often in complicated and fascinating ways. Recognizing this mixed nature will allow future research to investigate how contingency and determinism interact. Many questions remain to be addressed; for example, what circumstances promote contingent and deterministic outcomes, how does the extent of prior genetic divergence affect the propensity for future parallelism versus contingency, what types of divergence—say, a few mutations of large effect versus the accumulation of minor variants over long periods—lead to which outcomes, and what circumstances allow convergence even in distantly related taxa? Theory and experiments show that the structure of the adaptive landscape plays a critical role in determining the potential for contingent outcomes. Therefore, a deeper understanding of adaptive landscapes will be important for understanding evolutionary contingency. In short, there’s no shortage of work to do, and interesting outcomes to be discovered and quantified. Gould would be pleased that the field he inspired has such bright prospects, as the tape of life plays on.They’re basically thinking that they can have their cake and eat it, too.Are these evolutionists really seeing patterns in nature emerging by Darwin’s theory? A press release from Uppsala University warns, “Well established theories on patterns in evolution might be wrong.” The top illustration is the “march of man” icon. In the article, Graham Budd and Richard Mann argue that many of the famous patterns and trends evolutionists claim to see in the fossil record, including instances of diversification and extinction, are artifacts of their own biases.This makes no sense except to those drunk on Darwine. Think about it: we’ve shown that natural selection is merely a restatement of the Stuff Happens Law (SHL, see 13 Oct 2018). It’s the absence of a law of nature. It’s the absence of scientific explanation. It’s the abdication of science, merely concluding, “stuff happens.” How can a blind, aimless, purposeless process be anything else? This doesn’t mean that the SHL is incapable of keeping scientists busy. For analogy, imagine these same scientists studying Brownian motion. They ask themselves, “If we replay the tape of Brownian motion, can we predict what will happen?” For years, they make measurements and charts of paths that particles take under Brownian “forces” (although it is not a force, either, but an effect of blind, aimless, purposeless chance events). For decades, they debate whether the tape of Brownian motion is deterministic or contingent. Sometimes the particle seems to make progress in one direction. Other times, it goes nowhere. Sometimes, two paths appear to ‘converge’ on the same direction. Now, picture the government throwing money to these scientists to keep them busy. Finally, after a lot of wasted effort, they conclude, ‘Clearly, Brownian motion can be both contingent and deterministic, and often in complicated and fascinating ways.’ Is humanity better off for knowing this? Is it a good example of scientific progress?Someone will complain that the analogy is flawed, because natural selection has a goal – fitness! If an organism does not survive, it drops out of the gene pool, unlike particles under Brownian motion. Such a criticism errs, because fitness is just as vacuous as the SHL. It can mean anything, as we showed in “The Story of Evolution” (13 Oct 2018). Evolution can move up, down, backward, forward or sideways. Natural selection doesn’t care. If the organism goes extinct, so what? It’s like the particle under Brownian motion dropping off the slide. Brownian motion doesn’t care, and neither does natural selection. The analogy holds. No matter what happens – good, bad or indifferent – evolutionists are all too content to say, “It evolved,” and claim their work has produced “understanding.”Do you see why we call Darwinian evolution “job security for storytellers”? (25 June 2014). These Darwine-oholics need to sober up and unlock the door. (Visited 320 times, 1 visits today)FacebookTwitterPinterestSave分享0
A 2016 matric learner from Durban’s Westville Boys’ High School who earned seven distinctions in his final exams last year has been accepted to study at Harvard University, one of the US’s premier Ivy League institutions.Sasasa Dlamini, a Class of 2016 matriculant from Westville Boys’ High School in Durban, has earned a spot to study at the esteemed Harvard University in the US. He will study economics and philosophy. (Photo: Wikipedia)CD AndersonThe 17-year-old Sasasa Dlamini is determined to use his Harvard opportunity to learn from the world’s best and invest the knowledge he gains back into South Africa. Ivy League universities are some of the most renowned in the world, with particularly stringent entry requirements and high educational standards, even for American students.“I want to engage with people from different backgrounds from me, and truly broaden my horizons and my understanding as a global citizen,” Dlamini says. “I’ve worked hard and played to my strengths… I want to stretch myself and my ability to help change the circumstances of people.”Congratulations to SA student, Sasasa Dlamini, he has been accepted to Harvard University where he’ll be studying Philosophy and Economics. pic.twitter.com/0eYQy0eCzb— TransAfricaRadio (@TransAfrica872) January 10, 2017In addition to his excellent exam results, Dlamini took part in a number of the school’s extracurricular activities, including debating, where he represented the province at national level, athletics and basketball.Applying to Harvard, Dlamini says, was a lengthy, intricate process. “It took me six months to prepare my application, which included four motivation essays, as well as a Skype interview. I had to take the SATs test.”The SATs are the admissions test for American universities.With a 6% admission rate, he kept his hopes realistic and got down to achieving his final matric marks, which would boost his chances of acceptance. “I didn’t tell my parents because I didn’t want them to have to share in my possible rejection.”But the news was good, and he got word in early January that he was welcome to attend Harvard in September, the start of the American academic year.Dlamini plans on studying economics and philosophy, ultimately hoping that the education will help him find new, innovative ways to develop more practical job creation ideas in South Africa.“We need job creation that is sustainable. Wealth accumulation is a problem here and it is a structural issue. We need to be looking at a far wider wealth distribution. Philosophy teaches you how to think and expand your ideas.”Proud parents Nicholas and Thelma Dlamini have faith their son will succeed, thanks in part to their instilling the true value of education in their three children from an early age. They also pay special tribute to the teachers and headmaster of Westville Boys’ High School, whose work with learners, they call “(an) epitome of what a school should be in our South African context in terms of transformation”.While standards for acceptance to American educational institutions are high, most of the Ivy League universities and other state colleges are open to hard working, qualifying students from around the world. Thanks to a number of specialist education advisers in South Africa, exceptional high school learners and tertiary students interested in studying overseas can find guidance to the processes, receiving comprehensive information about all accredited foreign institutions.Applicants are also taken through orientation sessions and individual consultations that help them not only prepare academically, but also adjust socially to the experience.For more information, please visit the official EducationUSA website.Source: Good Things Guy website
South Africa is implementing a sugar tax in April this year. Government and health authorities hope it will curb non-communicable diseases and obesity. Researchers from the University of Pretoria investigate how effective the tax will be.The sugar tax, effective 1 April 2017, can contribute to curbing diseases such as diabetes and reduce obesity. Researchers say non-communicable diseases have a significant impact on economic development. (The Conversation)Hettie Carina Schönfeldt, Beulah Pretorius and Nicolette HallSouth Africa’s planned sugar tax has come under severe scrutiny from its parliamentarians. The questions they’re grappling with are whether the country needs a tax and how effective it will be.The tax is planned to take effect on 1 April 2017. It’s designed to reduce sugar intake from sugar-sweetened beverages by upping the price with a 20% fiscal tax.The South African health authorities’ plan to issue a sugar tax must not be seen in isolation. It is part of the South African National Department of Health’s strategic plans to prevent and control non-communicable disease, and obesity.These strategies have set the ambitious target of reducing obesity by 10% by 2020. And they include salt reduction legislation, trans-fat regulations, and stricter label and advertising regulations.The reality is that the move to introduce the sugar tax is necessary because of the scourge of non-communicable diseases and obesity in the country.The rise of non-communicable diseases It is not unusual for populations that modernise as a result of socioeconomic development to have changes in their dietary patterns.But the move from traditional foods to more processed and convenience foods is linked to weight gain and an increased risk of developing diet-related non-communicable diseases such as high blood pressure, heart disease and diabetes.Non-communicable diseases have become the leading causes of death in low- and middle-income countries. South Africa is no exception. It has the highest rates of overweight and obese adults in Africa. Nearly one in every seven South African women is affected. And 40% of deaths from non-communicable conditions among men occur before they turn 60.In its second National Burden of Disease Study South Africa’s Medical Research Council tracked mortality levels and trends for non-communicable diseases between 1997 and 2012. It found that by 2010 non-communicable diseases had become one of the top causes of death in the country. They accounted for 39% of all fatalities putting them on par with the number of people dying from HIV/AIDS and tuberculosis combined.The World Health Organisation predicts that by 2020 these diseases will account for 80% of the global burden of disease. They will be responsible for seven of every 10 deaths in developing countries.Currently, a third of these premature deaths in lower income countries occur in people under the age of 60. In high income countries the proportion is only 13%.The impact of non-communicable diseases has a significant impact on economic development. The accumulated loss to South Africa’s gross domestic product between 2006 and 2015 from diabetes, stroke and heart disease was estimated at US$1.88 billion. The World Economic Forum has estimated that other industrialised countries such as Brazil, China, India and the Russia lose more than 20 million productive life years annually to non-communicable diseases.An obese nationIn addition to sharp increase in non-communicable diseases, obesity has also risen at an exponential rate. The number of overweight and obese children in South Africa has increased from 1.4% in 1994 to more than 15% in 2004.And the obesity phenomenon has come about before South Africa has been able to win the battle against under-nutrition. While there has been a rise in the number of overweight and obese people, many are still undernourished because their food choices deprive their bodies of essential nutrients (energy, vitamins and minerals).The changes in South Africans’ dietary patterns over time have included: more foods rich in total and saturated fats, less legumes and vegetables, and more energy-dense, micronutrient-poor snack foods, convenience foods, vegetable oils, and more sweetened products and beverages.Adding salt, sugar, fats and oils during food preparation has also increased. Although studies show that people are eating more fruit and meat than 10 years ago, people are still not consuming enough variety of foods to meet all the recommended macro- and micro-nutrients for optimal health and wellbeing.Global commitmentsAs the world continues to win battles against HIV/AIDS and other communicable diseases, the national burden of disease attributed to non-communicable diseases is expected to intensify.In the next 10 years it is estimated that the global non-communicable disease burden will increase by 17%. In Africa, this figure will be closer to 27%.Globally governments are being forced to pay more attention and intensify their actions against these diet-related diseases. As a member state to the United Nations, South Africa has signed various global resolutions and commitments on food and nutrition. By implementing the sugar tax, South Africa is simply heeding to its international commitments.Associate professor Hettie Carina Schönfeldt, Beulah Pretorius and Nicolette Hall are researchers in human nutrition and food composition at the University of Pretoria. The article was originally published in The Conversation. Read the original article.Would you like to use this article in your publication or on your website? See Using Brand South Africa material.