Commentary

Did your science textbook teach that peppered moths prove evolution?

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Here’s a post by Jonathan Wells at Evolution News, which re-caps the history of the peppered moths experiment.

Excerpt: (links removed)

The peppered moth story is familiar — even overly familiar — to most readers of ENV, so I will summarize it only briefly here. Before the industrial revolution, most peppered moths in England were light-colored; but after tree trunks around cities were darkened by pollution, a dark-colored (“melanic”) variety became much more common (a phenomenon known as “industrial melanism”). In the 1950s, British physician Bernard Kettlewell performed some experiments that seemed to show that the proportion of melanic moths had increased because they were better camouflaged on darkened tree trunks and thus less likely to be eaten by predatory birds.

Kettlewell’s evidence soon became the classic textbook demonstration of natural selection in action — commonly illustrated with photos of peppered moths resting on light- and dark-colored tree trunks.

By the 1990s, however, biologists had discovered several discrepancies in the classic story– not the least of which was that peppered moths in the wild do not usually rest on tree trunks. Most of the textbook photos had been staged.

In the 2000s the story began disappearing from the textbooks. British biologist Michael Majerus then did some studies that he felt supported the camouflage-predation explanation. But before he died of cancer in 2009, he only managed to publish a report of his study in the Darwin lobby’s in-house magazine Evolution: Education and Outreach. Now four other British biologists have presented his results posthumously in the Royal Society’s peer-reviewed Biology Letters. In an accompanying supplement, the authors presented their version of what they call “the peppered moth debacle.” And a debacle it certainly is, but not in the way they think.

According to Charles Darwin, natural selection has been “the most important” factor in the descent with modification of all living things from one or a few common ancestors, yet he had no actual evidence for it. All he could offer in The Origin of Species were “one or two imaginary illustrations.” It wasn’t until almost a century later that Kettlewell seemed to provide “Darwin’s missing evidence” by marking and releasing light- and dark-colored moths in polluted and unpolluted woodlands and recovering some of them the next day. Consistent with the camouflage-predation explanation, the proportion of better-camouflaged moths increased between their release and recapture.

Throughout the 1970s and 1980s, however, researchers reported various problems with the camouflage-predation explanation, and in 1998 University of Massachusetts biologist Theodore Sargent and two colleagues published an article in volume 30 of Evolutionary Biology concluding “there is little persuasive evidence, in the form of rigorous and replicated observations and experiments, to support this explanation at the present time.” (p. 318)

The same year, Michael Majerus published a book in which he concluded that evidence gathered in the forty years since Kettlewell’s work showed that “the basic peppered moth story is wrong, inaccurate, or incomplete, with respect to most of the story’s component parts.” (p. 116) In a review of Majerus’s book published in Nature, University of Chicago evolutionary biologist Jerry Coyne wrote: “From time to time, evolutionists re-examine a classic experimental study and find, to their horror, that it is flawed or downright wrong.” According to Coyne, the fact that peppered moths in the wild rarely rest on tree trunks “alone invalidates Kettlewell’s release-and-recapture experiments, as moths were released by placing them directly onto tree trunks.”

In 1999, I published an article in The Scientist summarizing these and other criticisms of the peppered moth story, and in 2000 I included a chapter on peppered moths in my book Icons of Evolution. Then, in 2002, journalist Judith Hooper published a book about the controversy titled Of Moths and Men. Hooper accused Kettlewell of fraud, though I never did; my criticism was directed primarily at textbook writers who ignored problems with the story and continued to use staged photos even after they were known to misrepresent natural conditions.

Jonathan has actually written about a number of  misleading things that you may mind in Biology textbooks.

Here are the sections in his book “Icons of Evolution“:

  • The Miller-Urey Experiment
  • Darwin’s Tree of Life
  • Homology in Vertebrate Limbs
  • Haeckel’s Embroys
  • Archaeopteryx–The Missing Link
  • Peppered Moths
  • Darwin’s Finches
  • Four-Winged Fruit Flies
  • Fossil Horses and Directed Evolution
  • From Ape to Human: The Ultimate Icon

Dr. Wells holds a Ph.D in Molecular and Cell Biology from the University of California at Berkeley.

News

New study: relationships where babies are born before the marriage happens are more unstable

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From Family Studies.

Excerpt:

New research on the marital prospects of single mothers published in the August issue of the journal Demography has good and bad news… The good news is that biological father marriages are more enduring than stepfather marriages. In other words, saying yes to her daughter’s father means that she is more likely to stay married than if she had said yes to someone else. The bad news is that even though she opted for the better bet, the odds are still stacked against her marriage lasting.

[…]“Among marriages that involved a black mother and a biological father,” she found, “20% had dissolved within five years, and 47% had dissolved within 10 years.”

Age and education of the mother did not do much to improve those odds.

More:

[…][V]ery few personal characteristics affected the divorce risk of women of any race in the study. Their husbands’ characteristics didn’t matter, either. Even though factors like age and education have been shown to matter quite a bit for ten-year divorce rates overall, they didn’t make a difference among the women that Gibson-Davis studied: those who gave birth outside of marriage.

[…]By showing that a single mother is most likely to marry her child’s biological father shortly after giving birth, and that such a marriage is less likely to end in divorce than marriage to another man, Gibson-Davis has provided some limited, encouraging evidence to those championing marriage promotion programs. Nevertheless, she correctly stresses that much work remains for those seeking to encourage single mothers to marry because enduring unions are relatively rare, even among biological parents. I have one window showing me why that is true. There are many others. The bottom line is that post-birth marriages are likely to be more difficult and less stable than others, and strengthening them is indeed an uphill battle.

If you’re like me, and you’re not having sex until you get married, now you know why. The old ways are best. Besides, when you take sex off the table, how the heck do you get a woman to like you? How does a woman get a man to like her? Oh, I have an idea. Men and women could think about how to show love for each other and how to help each other. Imagine that. That’s the way people used to have relationships. You actually had to put the work in then, and talk about things, instead of just jumping into bed after getting drunk with someone “hawt” that you just met at a party.

News

Dartmouth College won’t allow female student who is being stalked to arm herself

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Fox News reports on a story that shows you where the real war on women is. (H/T Lindsay)

Excerpt:

A 20-year-old Dartmouth student says she may have to give up her Ivy League dream and drop out of school because the prestigious college won’t allow her to carry a gun — to protect herself against a predator.

Taylor Woolrich, a junior, says Dartmouth administrators told her they won’t let her carry a gun on campus, even though she lives in fear of a man who has been stalking her since she was a high school student in San Diego.

“It’s absolutely unfair,” Woolrich said about her attempts to have the school make an exception to its weapons ban. “It’s one of the hardest things I’ve had to deal with.”

Woolrich was 16 years old and working in a San Diego café when she says a man came in to buy coffee and then kept returning throughout the day, staring at her for long periods of time and trying to flirt with her. The man, 67-year-old Richard Bennett, kept this up for days, she says, even sitting outside the store for an entire day and then following her home, demanding that she talk to him and saying he was “trying to protect her.”

She filed a restraining order, but it did little to keep Bennett away. Woolrich says he constantly harassed her during her first two years at Dartmouth, stalking her on social media and sending messages in which he “promised” to fly across the country to see her at college.

“I thought they were empty threats, but when I came home from school last summer, he was at my front door within eight hours of my plane landing,” she said. “That’s when I realized how serious it was.”

Woolrich and her family called the police, and Bennett was arrested. A search of his car uncovered a slip noose, a knife, gloves and other items.

And:

But Dartmouth administrators told her she was “absolutely not” allowed to carry a weapon on campus. She says she tried to plead her case and was told to speak with several campus officials, all of whom provided little to no help.

“There’s no option. There’s no one to go to. They don’t want to hear my case,” she said.

Many colleges across the country have banned guns on campus to prevent mass shootings and accidental shootings by irresponsible or inebriated students. But the pro-gun rights Crime Prevention Research Center, in a study published on Monday, said there have been no reported problems or issues with college-age permit holders on campuses in the nine states –  Colorado, Florida,Wisconsin, Utah, Pennsylvania,Oregon, Mississippi, Kansas and Idaho – whose laws mandate that students and others be permitted to carry concealed handguns on public college grounds.

“There’s this fear about the possibility of students causing problems, but people talk about these things without actual examples,” the center’s president, John Lott, told FoxNews.com. “By far, the safest course of action is to carry a gun for protection, especially for female victims.”

“[Woolrich] has legitimate concern,” he added. “There’s only so much a restraining order can do.”

Nothing to be concerned about, say the Darmouth College administrators. After all, we wouldn’t want anyone to be shot. Guns are so bad! But I’ve noticed that some people agree with the Dartmouth administrators, and think that it’s better for this woman to be raped and murdered, than for her to wave a handgun around to ward off her attacker. Now I disagree with these people, and I think that women should be encouraged to own guns, because they typically have less upper body strength than men, and guns equalize that. If anyone should be carrying a gun for self-defense, it’s a woman.

Let me explain again how gun ownership deters criminals from committing crimes, by appealing to academic studies.

A quick refresher on why people own guns

People own guns so that they deter criminals and reduce the crime rate in their communities. The more guns there are in the hands of law-abiding citizens, the lower the crime rate goes, because criminals don’t like being shot at by their crime victims.

Whenever I get into discussions about gun control, I always mention two academic books by John R. Lott and Joyce Lee Malcolm.

Here is a paper by Dr. Malcolm that summarizes one of the key points of her book.

Excerpt:

Tracing the history of gun control in the United Kingdom since the late 19th century, this article details how the government has arrogated to itself a monopoly on the right to use force. The consequence has been a tremendous increase in violent crime, and harsh punishment for crime victims who dare to fight back. The article is based on the author’s most recent book, Guns and Violence: The English Experience (Harvard University Press, 2002). Joyce Malcom is professor of history at Bentley College, in Waltham, Massachusetts. She is also author of To Keep and Bear Arms: The Origins of an AngloAmerican Right (Harvard University Press, 1994).

Upon the passage of The Firearms Act (No. 2) in 1997, British Deputy Home Secretary Alun Michael boasted: “Britain now has some of the toughest gun laws in the world.” The Act was second handgun control measure passed that year, imposed a near-complete ban on private ownership of handguns, capping nearly eighty years of increasing firearms restrictions. Driven by an intense public campaign in the wake of the shooting of schoolchildren in Dunblane, Scotland, Parliament had been so zealous to outlaw all privately owned handguns that it rejected proposals to exempt Britain’s Olympic target-shooting team and handicapped target-shooters from the ban.

And the result of the 1997 gun ban:

The result of the ban has been costly. Thousands of weapons were confiscated at great financial cost to the public. Hundreds of thousands of police hours were devoted to the task. But in the six years since the 1997 handgun ban, crimes with the very weapons banned have more than doubled, and firearm crime has increased markedly. In 2002, for the fourth consecutive year, gun crime in England and Wales rose—by 35 percent for all firearms, and by a whopping 46 percent for the banned handguns. Nearly 10,000 firearms offences were committed.

[…]According to Scotland Yard, in the four years from 1991 to 1995 crimes against the person in England‟s inner cities increased by 91 percent. In the four years from 1997 to 2001 the rate of violent crime more than doubled. The UK murder rate for 2002 was the highest for a century.

I think that peer-reviewed studies – from Harvard University, no less – should be useful to those of us who believe in the right of self-defense for law-abiding people.

A more recent study – from 2014

A new study that was in the news confirms these findings. Newsmax reported on it.

Excerpt:

A recent study showing a reverse correlation between concealed weapons and murder rates has renewed the contentious national debate about the effect of gun controls on violent crime.

Reason magazine reported last week on economist Mark Gius’ study of gun controls, published in the journal Applied Economics Letters showing states with restrictions on concealed weapons had higher gun-related murder rates than other states.

The study looked at the effects on murder rates of both state-level assault weapons bans and concealed weapons restrictions from 1980 to 2009.

[…]The findings come as A 2007 study has been also getting a new look from those who dispute gun control efforts aimed at stemming gun violence, Boston magazine reported last summer.

In research first published in Harvard’s Journal of Public Law and Policy, criminologists Don Kates and Gary Mauser looked at the correlation between gun laws and death rates.

“International evidence and comparisons have long been offered as proof of the mantra that more guns mean more deaths and that fewer guns, therefore, mean fewer deaths,” the pair wrote in their introduction. “Unfortunately, such discussions [have] all too often been afflicted by misconceptions and factual error and focus on comparisons that are unrepresentative.”

The pair found “correlations that nations with stringent gun controls tend to have much higher murder rates than nations that allow guns.”

It’s not a reasonable position to think that disarming law-abiding citizens will reduce crime rates. The evidence is against it.