Tag Archives: Scientific Method

December 18, 1912 (a Wednesday)

Working at Piltdown.

On this date, the discovery of the skull known as Piltdown man, the first important fossil human skull ever to be unearthed in England, was announced at a meeting of the Geological Society of Great Britain. Charles Dawson, steward of Barkham Manor, an attorney, and secretary to the Sussex Archaeological Society, and Arthur Smith Woodward, keeper of geology at the British Museum, announced their remarkable find had been made at Piltdown Common. The specimen, known as Piltdown man, occupied an honored place in the catalogues of fossil hominids for the next 40 years. But in 1953, thanks to some rigorous scholarly detective work, Piltdown man was revealed to be nothing more than a forgery, manufactured from modern human and animal remains.

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Assaulting Science

I have just discovered another incarnation of pseudo-science on the internet, this one promoted by a Libb Thims:

In short, Thims’ research efforts, beginning in 1995 as a curious hobby, and in 2001 as a more intense research project, have been to understand how the inequality ΔG < 0, where ΔG = ΔH – TΔS, applies to the governance and regulation of human existence, impersonally (in relationships) and socially (within a society), viewed purely in terms of a super-observer perspective, time-accelerated human reactions (surface-attached chemical reactions) point of view—in other words, in variational speak, how differentials (time variations) of Gibbs free energy change dG (available energy release or absorption) apply to the prediction and spontaneities of interactions and reactions between people, particularly in regards to the formation and dissolution of bonds, the intimate relationship marriage bond and reproduction in particular, over the course of decades of time (changes in states of experience). In categorization terms, this defines Thims as a human free energy theorist, a rare group of about forty thinkers. [emphasis added]

The amount of disinformation on the internet is truly horrendous.

A Case of Correlation not Causation

ResearchBlogging.orgA scientific study entitled, “Multiple aspects of sexual orientation: Prevalence and sociodemographic correlates in a New Zealand national survey” recently appeared in the Archives of Sexual Behavior. The abstract was published online on 22 June 2010:

Sexual orientation consists of multiple components. This study investigated both sexual identity and same-sex sexual behavior. Data came from the New Zealand Mental Health Survey, a nationally representative community sample of New Zealanders aged 16 years or older, interviewed face-to-face (N = 12,992, 48% male). The response rate was 73.3%. Self-reported sexual identity was 98.0% heterosexual, 0.6% bisexual, 0.8% homosexual, 0.3% “Something else,” and 0.1% “Not sure.” Same-sex sexual behavior with a partner was more common: 3.2% reported same-sex sexual experience only and 1.9% reported both experience and a relationship. For analysis of childhood and lifecourse, five sexuality groups were investigated: homosexual, bisexual, and heterosexual divided into those with no same-sex sexual experience, experience only, and experience and relationship. The non-exclusively heterosexual groups were more likely to have experienced adverse events in childhood. Educational achievement and current equivalized household income did not differ systematically across the sexuality groups. Only 9.4% of the exclusively heterosexual lived alone, compared with 16.7% of bisexuals and 19.0% of homosexuals. Heterosexuals were more likely than bisexuals or homosexuals to have ever married or had biological children, with differences more marked for males than for females. Heterosexuals with no same-sex sexual experience were more likely to be currently married than the other two heterosexual groups. Restricting comparisons to heterosexual, bisexual, and homosexual identification ignores the diversity within heterosexuals. Differences between the bisexual and homosexual groups were small compared with the differences between these groups and the exclusively heterosexual group, except for sex (80.8% of bisexuals were female).

Of people who reported certain traumatic childhood events, including sexual assault, rape, violence to the child, and witnessing violence in the home, 15 percent were not heterosexual; of those without such experiences, only 5 percent were not heterosexual, suggesting that such experiences tripled the chance of later homosexual or bisexual identification. Although sexual or physical abuse in childhood was associated with adult homosexuality, other traumatic experiences, such as the sudden death of a loved one or serious childhood illness or accident, were only slightly associated with non-heterosexual identity or behavior.

The authors are J. Elisabeth Wells and Magnus A. McGee, who are both in the Department of Public Health and General Practice, University of Otago, New Zealand and Annette L. Beautrais, who is affiliated with both the Department of Psychological Medicine, University of Otago and the Department of Emergency Medicine, Yale University School of Medicine. The journal is peer-reviewed, so these authors are not hacks.

However, I find some aspects of the report disturbing because of their potential to mislead non-scientists (and even some scientists).

  • Wells, in commenting publicly about the study, revealed her assumption that homosexuals are made, not born. This is a major glaring flaw, since existing research has not produced conclusive findings indicating grounds for such an assumption. “People who either identify themselves as homosexual or bisexual, or have had a same-sex encounter or relationship, tend to come from more disturbed backgrounds,” she remarked. “You could say that if someone was sexually abused as a child, chooses to live as a homosexual and lives life well, then that is not a bad thing. But if they are living a homosexual life and regretting it, that is another matter.”
  • More importantly, I seriously doubt the credibility of this study because all of the ratios are way off. Of the sample who provided responses, ninety-eight percent identified as heterosexual, only 0.8 percent homosexual, and only 0.6 percent bisexual. Of those who identified as bisexual, 80 percent were women. This study is seriously skewed. The responses were all obtained in face-to-face interviews, which in sex studies are known to lead to under-reporting by sexual minorities. Self-reporting, even when obtained by questionnaire, is unreliable in sex studies. For example, homosexuals are probably less likely to identify as such because of homophobia in society. And are self-avowed homosexuals more — or less — likely to reveal that they were victims of child sex abuse than heterosexuals? They may be more comfortable talking about their sex lives and therefore more inclined to report childhood abuse. On the other hand, heterosexual males, less comfortable with discussing sex or seeing themselves as victims, may be far less likely to admit that they were sexually abused as children.
  • It is always important in scientific studies to distinguish between correlation and causation. This study reveals only a correlation between childhood abuse and later homosexual identification. It does not and, in fact, cannot demonstrate a causal connection — that child abuse causes homosexuality. To conclude so would be as illogical as saying that lynchings cause brown skin, or wearing skirts causes breast cancer. Perhaps homosexual identification causes child abuse — in other words, maybe homosexual children are more likely to be victims because of bigotry against them? Independent evidence — namely, the most comprehensive report ever on the experiences of lesbian, gay, bisexual and transgender (LGBT) students in the United States, The 2007 National School Climate Survey — indicates that this is likely. The survey of 6,209 middle and high school students conducted by the Gay, Lesbian, and Straight Education Network (GLSEN) found that nearly 9 out of 10 LGBT students (86.2 percent) experienced harassment at school in the past year, three-fifths (60.8 percent) felt unsafe at school because of their sexual orientation, and about a third (32.7 percent) skipped a day of school in the past month because of feeling unsafe. This survey, of course, did not address abuse in the home arising out of homosexual identification.

Homophobic bullying.

Tony Simpson, chairman of the national LGBT group Rainbow Wellington in New Zealand, said that the research should not be taken to mean that homosexuals are not born that way. “I have no doubt that the religious right will leap to the conclusion that this goes to show conclusively that homosexuals are made rather than born,” he said. As he predicted, the study was reported on LifeSiteNews.com, an antigay religious-right Web site.

However, the scientific and medical consensus is clear: homosexual orientation is not the result of choice. There is probably a combination of genetic and biological factors that cause people to become gay. Choice and willfulness have nothing to do with who is and is not homosexual (or heterosexual). Someone who falls in love with a member of their own sex has no more choice over their sexual orientation than someone who falls in love with a member of the opposite-sex. The only choice is whether to embrace and celebrate one’s orientation, or to be ashamed and hide.

Suggested Reading:

A Tale of Two Hypotheses

ResearchBlogging.orgThe cause of the rapid evolutionary growth in hominid brain size remains a mystery and a major point of contention among anthropologists. (Hominids are humans and human-like primates). Our brains weigh roughly twice as much as those of our similarly-sized earliest human relative, Homo habilis, which lived two million years ago. Also, humans have extraordinarily large and complex brains compared with non-human modern primates. The human brain is several times larger than that of the macaque monkey – even after correcting for body size – and it is far more complicated in terms of structure. Although humans weigh about 20 percent more than chimpanzees, our closest living relative, the human brain weighs 250 percent more. And keep in mind that a huge brain is a serious investment – neural tissue guzzles a lot of energy.

Two main hypotheses have been proposed to explain why humans have evolved larger brains than their primate relatives:

  • The general intelligence hypothesis suggests that bigger brains make humans better and faster at all kinds of cognitive skills, such as memorizing, learning, and planning ahead. In other words, humans differ from apes uniformly across physical and social cognitive tasks because they have greater general intelligence. Physical skills involve understanding concepts of space, quantities, and causality. Social skills involve understanding nonverbal communications, imitating another’s solution to a problem, and understanding that other individuals have their own beliefs and intentions. For example, biting and trying to break a plastic tube to retrieve the food inside demonstrates a physical skill, while following another’s example to pop open the tube to retrieve the food demonstrates a social skill.
  • The cultural (or social) intelligence hypothesis says that bigger brains have enabled humans to develop, in particular, more complex social cognitive skills to interact in cultural groups.

One way to distinguish between these two hypotheses is to compare the cognitive abilities and skills of humans with other non-human primates. If the general intelligence hypothesis is true, then we expect to see a difference between humans and apes in both physical and social skills. If the cultural intelligence hypothesis is true, then we expect to see a difference primarily in social skills.

This experiment is exactly what was performed by Esther Herrmann and her colleagues of the Max Planck Institute for Evolutionary Anthropology in Leipzig, chimptalk.jpgGermany, and recently reported in the September 7 issue of the journal Science. They put 105 young German children (Homo sapiens), 106 chimpanzees (Pan troglodytes), and 32 of the more evolutionarily distant orangutans (Pongo pygmaeus) through a series of complex tests. The children were all about 2.5 years old, an age when they have about the same physical skill level of chimpanzees, and had been speaking for at least a year. The apes ranged in age from 3 to 21 and had all been made accustomed to humans. The researchers designed 16 different puzzles to tease out the differences in ability between humans and apes. The tests took between three and five hours and were spread between five and eight days over two weeks. The apes were tested in the sanctuaries where they live in Africa and Indonesia.

The results found that chimpanzees, human children, and orangutans were all equally successful in the physical skills tests. But the human children were significantly better at the social skills tests – scoring around 74 percent correct on the tests compared to scores of 33 percent from both groups of apes.

The findings support the cultural intelligence hypothesis but contradict the general intelligence hypothesis. Joan Silk, an anthropologist at the University of California, Los Angeles, who was not involved in the study, observed that “compared [with] baboons we waste an awful lot of time gossiping about one another.” Aside from gossiping, these increased social skills appear to carry strong evolutionary advantages, enabling humans to sustain relationships with others and help each other out in times of need. A growing body of evidence suggests that the quality of social relationships has measurable fitness consequences for individuals. However, this may have come with some hidden costs. Silk commented that “the human brain is a really complicated machine that goes wrong with some frequency. Mental illness may be the evolutionary cost of this complexity.”

References:

  • Herrmann, E., Call, J., Hernandez-Lloreda, M.V., Hare, B., Tomasello, M. (2007). Humans Have Evolved Specialized Skills of Social Cognition: The Cultural Intelligence Hypothesis. Science, 317(5843), 1360-1366. DOI: 10.1126/science.1146282
  • Silk, J.B. (2007). Social Components of Fitness in Primate Groups. Science, 317(5843), 1347-1351. DOI: 10.1126/science.1140734

Common Nonsense

I was doing some Internet surfing recently when I came upon a post entitled “Evolutionist Fundamentalism.” Normally, I ignore these rants, as they are usually written by people who are so sure they are correct that it is pointless to try to reason with them. (Of course, I am also convinced I am correct, but I have logic and, more importantly, empirical evidence on my side. But more on this later.) However, this time the misconceptions were ones I am sure are on the minds of many non-scientists and are therefore worth addressing.

The post was written by a woman named Nonni. She begins:

I went back to college as an “older woman”. I started taking biology courses, thinking I would like to be a health educator or writer. I immediately ran up against what I saw as absolute dogma regarding the theory of evolution. As a much younger person I had learned evolution was one theory to explain the origin of biological complexity. However when I learned a single cell has over 300 different chemical reactions needed for its metabolism, not to mention its reproduction, I thought to myself–”what a marvelous design”. Design made sense.

This is like waving a red flag in front of a bull. First of all, nothing in science is “received doctrine” or “absolute dogma.” Anyone the least bit familiar with the history of science will realize that scientists can make conclusions only by using the best empirical (meaning observable and/or measurable) evidence available to them – and as new observations are made and new experiments done, it often becomes necessary to revisit previous conclusions and change them. It may take awhile, but nevertheless, it happens. (Furthermore, scientific knowledge is determined by consensus and informally within the scientific community. There is no referendum, plebiscite, or authority that rules on the veracity of a scientific claim.)

As a result, we say that scientific knowledge is “provisional.” Of course, then opponents go to the opposite extreme and say that since nothing in science is certain, scientific knowledge must be “worthless.” Let me point out that, philosophically speaking, nothing in life is certain. (And if you think otherwise, you are fooling yourself.) For example, the verdict of a jury in a criminal trial about a defendant’s guilt is provisional in the same way that a conclusion in science about the truth of a claim is provisional. In both cases, the standard of justification is “empirical evidence that convinces beyond a reasonable doubt.” Just as with conclusions in science, verdicts of juries sometimes have to be revisited when new evidence comes to light, sometimes years later. An 36974131-20120414.jpgexample of this occurred recently when the murder conviction of a 56-year-old man was overturned and he was freed after spending 25 years in prison. Willie Earl Green was convicted in the 1983 execution-style murder of a 25-year-old single mother in South Los Angeles. A judge ordered him released last Thursday, March 20, because the witness whose trial testimony had sent Green away for 33 years to life had recanted, and prosecutors decided not to retry Green. The witness, Willie Finley, explained that he was high on cocaine during the killing and had been “helped” by police to identify Green as a suspect. Likewise, the development of “DNA fingerprinting” has made possible the release of many innocent men who were falsely convicted of rape years ago, before this technology was available. Conclusions have to be made, and can only be made, by using the best evidence available at the time.

Back to Nonni. She continues:

There has been quite a lot of writing lately about evolution, and the possibility of intelligent design co-existing with it. Intelligent design answers questions regarding the unlikelihood that random selection could ever result in the vast complexity we see in biology. For the average person, it meets the standard of common sense. This is not creation science, biblical faith, or anything similar. However Intelligent Design theory is too uncomfortable for the belief system of the majority of evolutionists. Evolutionists resemble fundamentalists, in several ways.

So she says. First of all, the “random selection” she slips in introduces a “straw-man” argument. Natural selection is not “random selection,” but by saying it is, creationists can appeal to the “common sense” of the “average person” to make natural selection seem illogical. Instead, this line of reasoning illustrates the fact that Nonni really didn’t learn anything about evolution in her biology classes. Natural selection is the result of two things: individual variation and competition among members of a population. Individual variation is the result, ultimately, of mutation – and mutation is a random process. However, excess reproduction and limited environmental resources make competition among members of a population inevitable, and only those individuals with advantageous heritable traits (called adaptations) are likely to survive and produce healthy offspring. This is natural selection. Since more and more offspring inherit these advantageous heritable traits in each generation, these traits become more common – but there is nothing random about selection. Only certain, specific traits are preserved because, in the given environment, individuals with them have greater reproductive success.

Secondly, things happen in nature the way they do – whether or not they agree with our notion of “common sense.” For example, does Nonni know about quantum mechanics? It is a set of rules, the most successful of any in the history of science, that describes things that happen at the level of atoms and particles such as electrons, protons, and neutrons. Do a certain experiment with electrons and they behave like particles, but do a different experiment and they behave like waves. In the macroscopic world we live in, we know of nothing that behaves this way – in fact, we can’t even imagine something that behaves this way. The most unnerving idea in quantum mechanics may be the notion that certain particles can affect one another almost instantly across vast reaches of space. In 1935, sil14-e1-07a.jpgAlbert Einstein pointed out that synchronized atoms – “spooky action at a distance,” as he called it – are not only permitted by quantum mechanics but are an example of its absurdity. “No reasonable definition of reality could be expected to permit this,” he, Boris Podolsky and Nathan Rosen confidently wrote in a paper in 1935. However, far from demolishing quantum theory, that paper wound up as the cornerstone for the new field of quantum information – in fact, it is the most cited of Einstein’s papers. Long after Einstein’s death, experiments were finally performed in 1982 by Alain Aspect and his colleagues at the University of Orsay in France, the results of which confirmed quantum mechanics and not reality as Einstein had always presumed it should be. Paradoxically, Einstein had once written to a friend, “The more success the quantum theory has, the sillier it seems.”

Next, Nonni writes:

1. Scientific authority is deemed absolute in that the scientific community has determined what is and what is not to be included in the realm of scientific inquiry. If something is deemed to be outside the realm of scientific inquiry, it is to be denied existence entirely. Evolutionists will never say that the theory of Evolution also falls outside the realm of scientific inquiry. As an explanation for the origin of all biological forms, it technically does. The origin of all biological life simply cannot be observed, measured or reproduced. Intelligent Design, however, has been deemed to be outside the realm of scientific inquiry, although as a theory, it fits the facts of complexity better than random selection, which has mathematically impossible odds.

So many misconceptions, so little space. First, Nonni repeats her argument of natural selection as “random,” which, as I have pointed out, is a non-starter.

Secondly, Darwin’s theory of evolution, and the modern synthetic theory of evolution, have nothing to do with the origin of life on Earth. The theory does not deal with how life came to be on this planet – it only deals with how living things have changed over time since their first appearance. The evolution of living things has been observed, measured, and reproduced. Even if human beings were not present to see some of these events happen before their very eyes, I would point out that many things are accepted as true even when there are no eyewitnesses. Defendants have been convicted of murder (and executed) even when there were no eyewitnesses, as long as there was circumstantial evidence that convinced a jury of their guilt beyond a reasonable doubt. On the other hand, if I really didn’t want to believe that, say, George Washington ever existed, I would only have to argue that all the evidence – documents and artifacts alike – could have been forged and concocted by conspirators to make it look like he was a real person. But then, that would be “unreasonable doubt.”

Thirdly, the origin of “all biological life” can be investigated by science because hypotheses can be proposed that can be tested. Scientists can do experiments in the lab that simulate conditions as they may have existed on Earth some four billion years ago. These experiments confirm that life could have chemically evolved from inanimate matter under those conditions without the aid of any “intelligence.” There is no hypothesis that Intelligent Design can propose that can be tested because advocates have no idea (at least, when they are not at Church) who or what this Intelligence might be. This Intelligence, unless it can be empirically verified, is as good an explanation for the origin of “all biological life” as is Santa Claus. [However, this is not the same thing as claiming that an Intelligence (or Santa Claus) does not exist.] In short, an explanation must be testable to be scientific.

Now, Nonni gets nasty:

2. Scientists are the new prophets. They hold the keys of knowledge to which the rest of the world has limited access. One simply can’t argue with a scientist since everyone who is not a scientist is discounted as inferior and ignorant.

Somehow, here I think the pot is calling the kettle black. First, science is not a body of knowledge that has been revealed only to the “chosen” or the “elect” few. It is a basic assumption of science that anyone, in principle, can repeat observations and experiments to confirm the facts of science. Secondly, for someone who claims not to be able to “argue with a scientist,” she seems to be doing quite well. And I don’t think it is fair to say that all scientists consider anyone who argues with them to be “inferior and ignorant” – anymore than it is fair to say that all creationists who argue with scientists consider them to be “inferior and ignorant.” Although, on the issue of science and evolution, I think Nonni is misinformed and has much to learn.

But Nonni has more to say:

3. Evolutionary theory is now taught everywhere as fact, when it is in reality unproven theory. Since it is the only theory allowed under the criteria of scientific inquiry, it is the only theory available, and therefore is a fact.

Boy. I wish evolutionary theory was now taught everywhere as fact. It often is not taught at all in the public schools.

First, evolution is one of the most well-supported theories in science today. Her statement, again, illustrates her lack of knowledge about evolutionary biology. Maybe she is thinking of the “evolution is only a theory” canard promoted by creationists. In everyday usage, “theory” is often used in the sense of a guess or speculation. A hypothesis is an educated guess, but a theory is the goal of science – a set of related hypotheses about some natural phenomenon that has been tested repeatedly and extensively without being disproved. A theory is as close to the truth as science can get.

Secondly, the theory of evolution is not the only possible scientific explanation for the change we see in living things. However, the theory of evolution is the best explanation because the evidence overwhelmingly supports it better than any other. Creationists like to think that there are only two possible explanations for the diversity of the biological world, Intelligent Design or the theory of evolution, because then they mistakenly think it is an either/or situation. If they can show that evolution is false, they illogically think that that proves Intelligent Design is true. [In any case, Intelligent Design isn’t a scientific explanation since it can’t be tested.]

But there’s more from Nonni:

4. Where the theory of Evolution has gaps, inconsistencies or defies the knowledge of another discipline (i.e., mathematics), the truth of the theory must be taken on faith.

5. Universities are the new churches of Evolution. No one is admitted to the priesthood (faculty) unless they subscribe to the statement of faith. Evolution by random selection is an article of faith.

Now Nonni is really getting off the wall. I have heard this criticism from students. Evolution has “gaps.” Well, scientific knowledge has “gaps.” If this were not so, then there would be nothing left for scientists to investigate. We do research because there ARE things left to learn. But none of the so-called gaps in our knowledge of evolutionary biology in any way threatens or undermines the theory of evolution. Once again, Nonni refers to natural selection as “random selection,” preferring to defy the knowledge of biology. Finally, scientists do not rely on “faith” in evaluating the truth of a hypothesis or theory, because they don’t have to – they look at the empirical evidence. Her statement that “universities are the new churches of Evolution” is strident hyperbole, not worth responding to.

6. Whomever questions the doctrine of Evolution is an ignorant outsider, certainly unworthy of a teaching position, and probably also unworthy of a biological science degree.

This is how I see it. I went back to college as an “older woman”. Its very difficult for older people to go back to college. We have to overcome the common sense we’ve acquired through years of experience in living. But thats the subject of a whole new post–or maybe more.

Here, I detect a bit of sour grapes.

In conclusion, if you want to study science, or just become an educated person, you have to learn to critically evaluate what you think as rigorously as you critically evaluate what others think. This is how I see it.

References:

  • A. Einstein, B. Podolsky, and N. Rosen, “Can quantum-mechanical description of physical reality be considered complete?” Physical Review 41: 777 (15 May 1935).
  • A. Aspect, Dalibard, and G. Roger, “Experimental test of Bell’s inequalities using time-varying analyzers,” Physical Review Letters 49(25): 1804 (20 Dec 1982).