Posts about commentary

Promoting Open Science

As I have written many times in the past we need to take back science from the closed-science journals. Historically journals were useful (before the internet). With the advent of the internet (and its spread) instead of maintaining the mission they started with the journals sought to maximize their profit and their own pay and jobs at the expense of sharing scientific knowledge with the world.

Elsevier — my part in its downfall by Timothy Gowers provides another good look at what can be done to promote science, math and engineering by addressing the damage to that goal being done by closed science publishers.

Recently he announced the launch of Discrete Analysis, a new journal that publishes to arXiv.

Disrupting the subscription journals’ business model for the necessary large-scale transformation to open access from the Max Planck Digital Library provides some good ideas for how to promote science in spite of the closed science journals fighting that goal.

There needs to be a shared understanding that the money currently locked in the journal subscription system must be withdrawn and re-purposed for open access publishing services. The current library acquisition budgets are the ultimate reservoir for enabling the transformation without financial or other risks.

Related: The Architecture of Access to Scientific KnowledgeWhy Copyright Extension is a Very Bad IdeaPublishers Continue to Fight Open Access to Science (2007)Harvard Steps Up Defense Against Abusive Journal Publishers (2012)

The Downside of Adopting the Metric System

The only downside of adopting the metric system is less control over room temperature (based on my experience). Every ºC = ºF * 1.8 so have less control (when using only integers to control temperature as is the case in my experience).

Granted this could be solved easily by using .5 (option in air conditioning and heating controllers but in my experience they don’t) for Celsius. For Fahrenheit this works out to enough control for me. For Celsius in a fair number (lets say 15%) of systems it is a bit uncomfortable.

The specific circumstances add greatly to creating a problem. My guess is those that annoy me swing even further than 1 ºC, they move further in one direction in order to not turn on and off all the time. So maybe that moves to swings of 2 or 3 ºC at the measurement point. But that is another issue, the measurement on home (or hotel) systems is often 1 reader so the variation is often greater in other locations.

Add to that the imprecision of their measures, I don’t have good data, but I am confident that the measurement error is fairly high. I am pretty comfortable at about 25ºC for air conditioning. But in some places I am cold at 27º and others I am warm at 23º. It could be me, but I don’t think so (most of the time – sometimes it is me).

A long time ago I had some imprecise portable temperature gauge and while I wouldn’t stake my life on results based on it, it confirmed my feelings (when I felt it was warmer than the local reading said my device agreed and when I felt it was colder my device agreed). Hardly scientifically valid proof, but it made me more comfortable trusting my opinion on this matter anyway.

My guess is in a unit using ºF you often can be 4 or 5 degrees off (or more) in different locations. For some people that might be ok. But for me that often starts to be uncomfortable. If you convert the issue to that time 1.8 it is noticably worse.

Now in reality I don’t think it expands quite that much. While the manufactures balance the confusion of adding .5 to a Celsius controller and decide not to, I would think they don’t swing 1.8 times as far (in heating or cooling in order to not turn on and off all the time), but it is still let precise than using Fahrenheit integers. I believe (hope) they set their internal dynamics not based only on integers but could say for example turn off .5º past the setting and turn on when the conditions are .5º worse than the setting (so .5º too warm in the case of air conditioning, for example).

It is still lame the USA fails to adopt the metric system, but reducing this problem in the USA is one small benefit of holding off 🙂 I wonder if 1 in a million, 1 in 10 million… up to 1 in 7.2 billion people (just me, all alone in the world) have my concern for the lack of precision of heating and air conditioners when using the metric system.

Related: Google Lets Servers Stay Hot, Saving Air Conditioning CostsDo It Yourself Solar Furnace for Home HeatingUsing Algae Filled Window Panes to Provide Passive and Active Solar

George Box 1919 to 2013 – A Great Friend, Scientist and Statistician

Reposted from my management blog.

I would most likely not exist if it were not for George Box. My father took a course from George while my father was a student at Princeton. George agreed to start the Statistics Department at the University of Wisconsin – Madison, and my father followed him to Madison, to be the first PhD student. Dad graduated, and the next year was a professor there, where he and George remained for the rest of their careers.

George died today, he was born in 1919. He recently completed An Accidental Statistician: The Life and Memories of George E. P. Box which is an excellent book that captures his great ability to tell stories. It is a wonderful read for anyone interested in statistics and management improvement or just great stories of an interesting life.

photo of George EP Box

George Box by Brent Nicastro.

George Box was a fantastic statistician. I am not the person to judge, but from what I have read one of the handful of most important applied statisticians of the last 100 years. His contributions are enormous. Several well know statistical methods are known by his name, including:

George was elected a member of the American Academy of Arts and Sciences in 1974 and a Fellow of the Royal Society in 1979. He also served as president of the American Statistics Association in 1978. George is also an honorary member of ASQ.

George was a very kind, caring and fun person. He was a gifted storyteller and writer. He had the ability to present ideas so they were easy to comprehend and appreciate. While his writing was great, seeing him in person added so much more. Growing up I was able to enjoy his stories often, at our house or his. The last time I was in Madison, my brother and I visited with him and again listened to his marvelous stories about Carl Pearson, Ronald Fisher and so much more. He was one those special people that made you very happy whenever you were near him.

George Box, Stuart Hunter and Bill Hunter (my father) wrote what has become a classic text for experimenters in scientific and business circles, Statistics for Experimenters. I am biased but I think this is acknowledged as one of (if not the) most important books on design of experiments.

George also wrote other classic books: Time series analysis: Forecasting and control (1979, with Gwilym Jenkins) and Bayesian inference in statistical analysis. (1973, with George C. Tiao).

George Box and Bill Hunter co-founded the Center for Quality and Productivity Improvement at the University of Wisconsin-Madison in 1984. The Center develops, advances and communicates quality improvement methods and ideas.

The Box Medal for Outstanding Contributions to Industrial Statistics recognizes development and the application of statistical methods in European business and industry in his honor.

All models are wrong but some are useful” is likely his most famous quote. More quotes By George Box

A few selected articles and reports by George Box

Related: It is not about proving a theorem it is about being curious about thingsBox on QualitySoren BisgaardLearning Design of Experiments with Paper HelicoptersPeter Scholtes

Our Dangerous Antibiotic Practices Carry Great Risks

Our continued poor antibiotics practices increase the risk of many deaths. We are very poor at reacting to bad practices that will kill many people in the future. If those increased deaths happened today it is much more likely we would act. But as it is we are condemning many to have greatly increased odds of dying from bacterial causes that could be prevented if we were more sensible.

Resistance to antibiotics is becoming a crisis

Increasingly, microbes are becoming untreatable. Margaret Chan, director general of the World Health Organization, warned in March of a dystopian future without these drugs. “A post-antibiotic era means, in effect, an end to modern medicine as we know it,” she said. “Things as common as strep throat or a child’s scratched knee could once again kill.”

evidence is mounting that antibiotics are losing efficacy. Through the relentless process of evolution, pathogens are evading the drugs, a problem known broadly as antimicrobial resistance.

Europe has launched a $741 million, seven-year, public-private collaborative research effort to accelerate drug development.

Seeking new antibiotics is wise but the commentary completely ignores our bad practices that are causing the problem to be much worse than it would be if we acted as though bad practices that will lead to many deaths should be avoided.

Previous posts about practices we taking that create great risk for increased deaths: Antibiotics Too Often Prescribed for Sinus Woes (2007)Meat Raised Without Antibiotics is Sadly Rare Today (2007)Overuse of Antibiotics (2005)CDC Urges Increased Effort to Reduce Drug-Resistant Infections (2006)FDA May Make Decision That Will Speed Antibiotic Drug Resistance (2007)Antibacterial Soaps are Bad (2007)Waste Treatment Plants Result in Super Bacteria (2009)Antibiotics Breed Superbugs Faster Than Expected (2010)Antibiotics Use in Farming Can Create Superbugs (2010)What Happens If the Overuse of Antibiotics Leads to Them No Longer Working? (2011)Dangerous Drug-Resistant Strains of TB are a Growing Threat (2012)

Obviously bacteria evolve to survive the counter measures we currently have. The foolish practices of promoting ignorance of evolution leads to a society where the consequences of actions, and the presence of evolution, lead to bad consequences. We find ourselves in that society.

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Nice Interaction with a Group of Wild Mountain Gorillas Strolling Through Camp

An amazing encounter with a troop of wild mountain gorillas near Bwindi Impenetrable National Park, Uganda. The reality is that these many natural environments will be maintained only with economic incentives. A certain amount of wilderness can be maintained with economic support from outside (government, charity…). But reasonable accommodations to find ways to make retaining natural wonders economically viable are likely a key to saving much of these environments for the future. Unfortunately there are big incentives to destroy nature from those rich tourists who don’t follow the rules and push their guides to break the rules (guides often do this as they have seen great monetary rewards [in tips] for breaking the rules (bothering animals, going too close, going to off limits areas…). It is sad how often tourists at national parks show utter disregard for nature and preserving things for later generations.

It seems like this video wasn’t about that type of behavior though. Instead it is just an example of how cool nature can be at times. Animals are not quite as predictable as some believe. Like this group that wandered into the camp (as they do a couple times a year) animals often stray from their normal behavior.

Providing good jobs and sharing revenue from tourists with local residents (paying for schools…) is a very good way to encourage residents to support natural heritage sites. This is true in Africa and also near park in the United States, or anywhere else. Here is an example of an organization doing that: Conservation Through Public Health.

I am a huge fan of tying in economic benefits to natural parks and resources. I think this is part of making them not environmentally sustainable but economically sustainable. If the areas do not make a contribution to the economic well being of those living there, there is a danger the land will be tapped for uses that will damage their natural heritage value. We do have to be careful as often these economic interests can turn into greedy people just wanting whatever they can get now (I am saddened by how often tourists behave in this way at natural wonders).

People are going to determine how land is used. We can hope that purely altruistic motives will result in long preserved natural habitats. But I don’t think that hope is as sustainable as creating a situation where it is also in people’s economic interests to maintain the environments. A combination of altruistic, long term thinking and economic interest is more likely to preserve natural environment (in my opinion).

Related: Massive Western Lowland Gorilla Population in Northern Republic of CongoGrauer’s Gorilla (Eastern Lowlands Gorilla)African Parks (a business approach to conservation)Travel photos from National Parks

Encouraging Curiosity in Kids

How do you help make your children scientifically literate? I think the biggest thing you can do is encourage curiosity.

One way to encourage curiosity it is by answering their questions (and not saying: I am too busy, don’t bother me, don’t ask me?, stop asking why…). I know adults are busy and have all sorts of stuff we are trying to get done; and the question about why I need to wash my hands doesn’t seem worth answering. But I think anytime a kid is asking why is an opportunity to teach and encourage them to keep being curious.

It is very easy to shut off this curiosity, in our society anyway (we do it to the vast majority of people). The biggest difference I see between adults and kids is not maturity or responsibility but curiosity (or lack thereof in adults) and joy (versus adults who seem to be on valium all the time – maybe they are).

As they grow up kids will have lots of science and technology questions that you don’t know the answers to. If you want them to be curious and knowledgeable, put in the effort to find answers with them. You have to help them find the answers in a way that doesn’t turn them off. If you just say – go look it up yourself (which really they can do), maybe the 2% that are going to become scientists will. But most kids will just give up and turn off their curiosity a little bit more (until eventually it is almost gone and they are ready to fit into the adult world). Which is very sad.

Once you get them used to thinking and looking things up they will start to do this on their own. A lot of this just requires thinking (no need to look things up – once a certain base knowledge is achieved). But you need to set that pattern. And it would help if you were curious, thought and learned yourself.

Photo of kids intently studying on a Malaysian beach

My mom with a group of Malaysia kids apparently intent on learning something. I am there, but not visible in this photo. Photo by my father.

While walking in the park, see one of those things you are curious about and ask why does…? It is good to ask kids why and let them think about it and try and answer. Get them in the habit of asking why themselves. And in those cases when no-one knows, take some time and figure it out. Ask some questions (both for yourself – to guide your thinking – and to illustrate how to think about the question and figure things out). If you all can’t find an explanation yourselves, take some time to look it up. Then at dinner, tell everyone what you learned. This will be much more interesting to the kids than forcing them to elaborate on what they did today and help set the idea that curiosity is good and finding explanations is interesting.

It is fun as a kid if your parent is a scientist or engineer (my father was an engineering professor).

You often don’t notice traits about yourself. In the same what I know what red looks like to me, I figure we both see this red shirt you see the red that I do. But maybe you don’t. I tend to constantly be asking myself why. If I see something new (which is many, many times a day – unless I am trapped in some sad treadmill of sameness) I ask why is it that way and then try and answer. I think most of this goes on subconsciously or some barely conscious way. I actually had an example a few months ago when I was visiting home with my brother (who is pretty similar to me).

As we were driving, I had noticed some fairly tall poles that seemed to have really small solar panels on top. I then noticed they were space maybe 20 meters apart. Then saw that there seemed to be a asphalt path along the same line. I then decided, ok, they are probably solar panels to power a light for the path at night. Then my brother asked why are there those small solar panel on top of that pole?

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The Politics of Anti-Science

In the 1960’s the USA had an unrealistic view of how much studying and learning about science and engineering could do. Investing is science and engineering is an extremely wise economic (and cultural) endeavor but it isn’t going to solve all the problems that exist. Somehow today we find ourselves with a large number of politically powerful people we take strong anti-science positions. These tactics reduce funding and support for beneficial research and are short sited approaches to public administration. This is an unfortunate turn of events that is damaging the American economy and will have huge damages going forward.

Thankfully other countries have seen how wise investing in science and engineering is and have more than taken up the slack created by the anti-science community. Two favorite tactics of the anti-science leaders is to try and create confusion where there is none and to turn the focus away from serious matters and instead playing silly political games. The silly games will draw donors and voters so if they care about those things more than the country and the future of the country it is a sound tactic. The damage it causes the country however I would hope would limit the use of such tactics however that has not been the case recently.

‘Shrimp On A Treadmill’: The Politics Of ‘Silly’ Studies

Take the case of the “shrimp on a treadmill.” Burnett says the senator’s report linked that work to a half-million-dollar research grant. But that money actually went to a lot of different research that he and his colleagues did on this economically important seafood species.

The treadmills were just a small part of it, a way to measure how shrimp respond to changes in water quality. Burnett says the first treadmill was built by a colleague from scraps and was basically free, and the second was fancier and cost about $1,000. The senator’s report was misleading, says Burnett, “and it suggests that much money was spent on seeing how long a shrimp can run on a treadmill, which was totally out of context.”

John Hart, a Coburn spokesperson, said in an email that “our report never claimed all the money was spent on shrimp on a treadmill. The scientists doth protest too much. Receiving federal funds is a privilege, not a right. If they don’t want their funding scrutinized, don’t ask.”

What the politicians are doing is exactly what this spokesperson suggests – they are withdrawing from the anti-science culture created by some in Washington: they are moving their research to countries that support rather than attack science. That is a very bad thing for the USA. There are a number of very bad economic policies a government can take. Driving scientists and engineers into the arms of other countries is one of the worst.
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Career Prospect for Engineers Continues to Look Positive

As I have written previously the career prospects for engineers are bright around the globe. Many countries realize the importance of engineering and have taken steps to compete as a center of excellence for engineering. It is a smart economic policy. Ironically, the USA, that did such a great job at this in the 1960’s and 1970’s, has been falling down in this regard. A significant reason for this is the USA can only fund so many things and a broken health care system, military complex, bailouts to bankers (trust fund babies and others) cost a lot of money. You chose what to fund, and those are taking much of the available USA funds. There are also non-economic reasons, such as the turn in the last decade in the USA to make the barriers for foreigner engineers (and others) to go through to go to school, visit and stay in the USA have all increased dramatically.

Back to the prospects for engineers: their are shortages of good engineers all over (and the future projections don’t show any reason to believe this will change). Germany Faces a Shortage of Engineers:

In June, the Association of German Engineers (VDI) reported that there were 76 400 vacant engineering jobs—an all-time high.

Policymakers in Berlin have responded to the shortage of skilled workers with a number of measures, including changes in immigration rules that allow German companies to hire engineers from other countries, including those outside of the European Union. Among them: The annual salary that companies must pay foreigners has been lowered from 60,000 Euro (US $95,000) to 40,000 Euro, which is roughly the starting salary of an engineering graduate in Germany…

To make it easy for engineers to move around Europe, engineering associations and other groups across Europe are working with the European Commission (the executive arm of the European Union) to launch the new Engineering Card. The card, which German engineers can apply for now and other countries are planning to launch, provides standardized information about the engineer’s qualifications and skills for greater transparency.

“We don’t expect many engineers will come, because among other reasons, there is a shortage of engineers across Europe,”

Related: Engineering Again Dominates The Highest Paying College Degree ProgramsS&P 500 CEO’s: Engineers Stay at the TopChina’s Technology Savvy LeadershipEngineers: Future ProspectsEconomic Strength Through Technology Leadership

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What Happens If the Overuse of Antibiotics Leads to Them No Longer Working?

Antibiotics have been a miraculous tool to keep up healthy. Like vaccines this full value of this tool is wasted if it is used improperly. Vaccines value is wasted when they are not used enough. Antibiotics lose potency when they are overused. The overuse of anti-biotics on humans is bad (especially the huge amount of just lazy, not scientific use). But the massive overuse in livestock is much worse, it seems to me.

The health system in the USA is broken in a huge way in which it is broken is the failure to address creating systemic behavior that promotes human health and instead just treating illness. It is much better to avoid a situation where we breed super bugs and then try to treat those super bugs that have evolved to be immune to the antibiotics we have to use.

When antibiotics no longer work

While the source of the current salmonella outbreak remains murky, we can reasonably speculate about the genesis of the bug’s drug-resistance: the reportedly endemic overuse of antibiotics by the agricultural industry.

Drugs are given to livestock for multiple reasons. An obvious one is for the treatment of diseases. When livestock are sick, veterinarians administer a significant dosage in hopes of eliminating the animal’s affliction. Another reason is preventative. Animals in close quarters are more susceptible to infection, so farmers will often administer medicine to healthy animals in order to nip anything nasty in the bud. Most controversially, though, members of the agricultural industry use antibiotics for the express purpose of promoting livestock growth.

It’s a well-known, if not entirely intuitive, fact that healthy animals who are fed small, or “sub-therapeutic,” doses of antibiotics will wind up larger than their unmedicated counterparts. In many such cases, these drugs are given to livestock through their feed or water, and without the prescription or oversight of a veterinarian, according to Dr. Gail Hansen, a senior officer at the Pew Campaign on Human Health and Industrial Farming.

An estimated 80 percent of all antibiotics in the U.S. are given to food-producing livestock, according to the FDA. And approximately 83 percent of that medicine is “administered flock- or herd-wide at low levels for non-therapeutic purposes, such as growth promotion and routine disease prevention,” according to a lawsuit filed against the FDA in May. These figures could have very real consequences for public health, because the Catch-22 of this antibiotic abandon is the widespread development of drug-resistant bacteria, colloquially referred to as “super-bugs.”

In 2006, the European Union banned all use of antibiotics on livestock for growth promotion. And the U.S. Senate will consider similar legislation this year. Sen. Dianne Feinstein, D-Calif., reintroduced the “Preservation of Antibiotics for Medical Treatment Act” last month, which would significantly rein in agricultural drug use, and strictly prohibit the application of sub-therapeutic doses of drugs that have benefits for humans.

Still, the agricultural industry disputes data about its use of antibiotics and the rise of super-bugs, and it has aggressively fought efforts to legislate the matter. As a result, it’s hard to tell how far the legislation might proceed.

Related: Antibiotics Too Often Prescribed for Sinus WoesOveruse of Antibiotics (2005)FDA May Make Decision That Will Speed Antibiotic Drug Resistance (2007)

The end of the era of antibiotics

How did this happen? The driving forces are Darwin and human carelessness. Bacteria are constantly evolving, adapting to the changing conditions they face. Antibiotics usually kill bacteria. But sometimes a bacteria will develop a biological defense – particularly if too small a dose is used.

Antibiotics require a prescription in America, but our nation is still very much a part of the problem. Patients routinely demand these drugs, and doctors acquiesce, for respiratory infections and other ailments that will not respond to antibiotics because they are caused by a virus. We use soap with antimicrobial agents when regular soap does equally well. And we allow farmers to feed antibiotics to livestock in horrifying amounts, not to treat illnesses but to make farming more efficient.

The Potential Role of Concentrated Animal Feeding Operations in Infectious Disease Epidemics and Antibiotic Resistance

This working group, which was part of the Conference on Environmental Health Impacts of Concentrated Animal Feeding Operations: Anticipating Hazards—Searching for Solutions, considered the state of the science around these issues and concurred with the World Health Organization call for a phasing-out of the use of antimicrobial growth promotants for livestock and fish production. We also agree that all therapeutic antimicrobial agents should be available only by prescription for human and veterinary use.

Antibiotic Resistance in Livestock: More at Risk Than Steak
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Gravity and the Scientific Method

One of the topics I return to repeatedly is the scientific method – theories must to tested. As evidence mounts that new ideas do a good job of explaining theories they become more accepted. But they continue to be tested in new ways as the ideas are extended and ramification are explored. And science progress means that old conventions can be overturned as new evidence is gathered.

Science is not about current beliefs. Science is about seeking knowledge. If the search for knowledge leads to evidence that old ideas were wrong those ideas are overturned. Since people are involved that process isn’t as clean as it sounds above. People get comfortable with beliefs. They build careers on expanding those beliefs. Most are uncomfortable when they are challenged and don’t accept new ideas even when the evidence mounts. But some do accept the new ideas. Some challenge the new ideas by running experiments. And some of those prove the new ideas faulty. Some become convinced of the new ideas as the results of their experiments make the new ideas seem more sensible (instead of getting the results they expected).

Building the body of scientific knowledge is not nearly as clean and simple as most people think. It isn’t a simple process, what is the underlying truth can be debatable. But the beauty of the scientific process is how it helps us overcome our biases and provide evidence to support the theories we support. The scientific method (combined with our human involvement) doesn’t mean new ideas are accepted easily but it does mean new ideas compete on the basis of evidence not just the power of those that hold the beliefs.

Is gravity not actually a force? Forcing theory to meet experiments
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Ten Things Everyone Should Know About Science

As the writer of this blog (which is located at engineering.curiouscatblog.net) I am a strong believer in the importance of scientific literacy. Neil Degrasse Tyson stated the importance very well, as I mentioned in a previous post, the scientifically literate see a different world

If you are scientifically literate the world looks very different to you. Its not just a lot of mysterious things happening. There is a lot we understand out there. And that understanding empowers you to, first, not be taken advantage of by others who do understand it. And second there are issues that confront society that have science as their foundation. If you are scientifically illiterate, in a way, you are disenfranchising yourself from the democratic process, and you don’t even know it.

The Financial Times has complied a list of the 10 things everyone should know about science

  1. Evolution – previous posts: Evolution is Fundamental to Scienceposts tagged: evolution
  2. Genes and DNA – tags: genesgeneticsDNARNA
  3. Big bang – tags: physics, posts mentioning big bang
  4. Relativity – General Relativity Einstein/Essen Anniversary Test – posts mentioning relativity
  5. Quantum mechanics – Quantum Mechanics Made Relatively Simple Podcasts, Quantum mechanics
  6. Radiation
  7. Atoms and nuclear reactions
  8. Molecules and chemical reactions – posts on chemistry
  9. Digital data – I must admit, even reading their comments, I don’t understand what they are thinking here. There certainly is a great deal of digital data and the future certainly going to involve a great deal more, but this just doesn’t fit, in my opinion.
  10. Statistical significance – Seeing Patterns Where None Exists, Statistics Insights for Scientists and Engineers, Correlation is Not Causation post on statisticsexperimentation

It is a challenge to create such a list. I agree with most of what they have. I would like to look at changing the last 2 and radiation, though. I would probably include something about the scientific method rather than statistical significance. Another area I would consider is something about bacteria and/or viruses. You can maybe include them under genes, but viruses and bacteria are amazing in the very strange things they do with genes and I think that is worthy of its own item. Another possibility is thinking of separating out a second spot for things related to the scientific method – causation, randomized testing, multivariate experiments… I would also consider one, or more of the following or something related to them biology – chlorophyll, the the life of bacteria in our bodies, something related to human health (how drugs work, medical studies…), etc..

The Ten Things Everyone Should Know About Science

Evolution through natural selection remains as valid today as it was 150 years ago when expressed with great elegance by Charles Darwin in The Origin of Species. The mechanism of evolution depends on the fact that tiny hereditable changes take place the whole time in all organisms, from microbes to people.

An important feature of Darwinian evolution is that it operates at the level of the individual. There is no mechanism for natural selection to change the species as a whole, other than through the accumulation of changes that lead to the survival of the fittest individuals.

The rate of evolution varies enormously between different types of organism and different environmental circumstances. It can proceed very quickly when the pressure is great, as, for example, with bacteria exposed to antibiotics, when drug-resistant mutations may arise and spread through the bacterial population within months.

Why does it matter? Evolution is coming under renewed assault, particularly in the US, from fundamentalist Christians who want creationism to be taught in schools. Although evolution has had virtually unanimous support from professional scientists for at least a century, polls show that American public opinion still favours creationism.

Related: Poor Results on Evolution and Big Bang Questions Omitted From NSF ReportNearly Half of Adults in the USA Don’t Know How Long it Takes the Earth to Circle the SunScience Knowledge Quiz