Why science research still focuses mostly on males
In spite of a government mandate, females are often treated as afterthoughts in scientific research.
- A new study finds that though more females are included in experiments, sex-specific data often goes un-analyzed.
- Only about a third of studies analyzed published participant breakdown by sex.
- Some researchers say considering females more fully as research subjects is logistically too challenging.
In 2016, the National Institutes of Health (NIH) issued a directive that scientists receiving NIH funding must consider sex as a biological variable in pre-clinical research on vertebrate animals and human cells and tissues. According to a new study published in eLife that looked at over 700 journal articles, the number of women included as participants in pre-clinical research has jumped from 28 percent in 2009 to 49 percent in 2019. However, it's also unfortunately still the case that few studies actually consider sex as a biological influence that may potentially affect outcomes, and that data from women participants continues to be simply combined with data from men.
Study co-author Nicole C. Woitowich of Northwestern University's Feinberg School of Medicine tells INSIDE Higher Ed, "In the last 10 years, there has been a major in increase in sex inclusion, but it's still not where it's needs to be."
What's missing in current research
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Woitowich and others see two particularly problematic aspects to the continuing disregard of sex as a meaningful biological research variable.
First, female-specific data is rarely considered in study conclusions, despite the fact that it may have implications for women's health. According to L. Syd M Johnson of SUNY Update Medical University, who was not involved with the study, "This becomes highly problematic both scientifically and ethically, because women, children, and the elderly also need medical care, and they shouldn't be treated as if they have adult, male bodies. When they are excluded from research, and from the reported results, treatment for them becomes, effectively, off-label.
Second, Woitowich tells INSIDE Higher Ed it's, "troublesome to me as a scientist [that] a little under one-third [of studies] did not even report the number of males and females used as subjects." This makes it impossible for scientists to replicate the results. "If I don't have all the information," Woitowich says, "I'm left guessing."
On top of that, Woitowich laments that too much of the female-focused research that is undertaken is what's been called "bikini science," research surrounding issues related to female reproductive organs.
Why is this happening?
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"Many scientists, I don't even know if this is on their radar," says Woitowich. She proposes, therefore, that in the short term it may be the research gatekeepers — the funding entities, journal editors, and peer reviewers — who will have to step up and demand more inclusive science. She expresses surprise that they aren't already doing more to enforce the NIH's mandate. In the longer term, training for medical students should include a fuller awareness of the role that can be played by sex differences in research.
In a 2014 letter to the journal Nature, Janine A. Clayton and Francis S. Collins of the NIH admitted the problem even extends to female researchers. Noting that roughly half of the scientists doing NIH-funded research are women: "There has not been a corresponding revolution in experimental design and analyses in cell and animal research — despite multiple calls to action."
Another possible explanation
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There are some researchers who feel that a greater inclusion of women and their data in studies would unnecessarily complicate the problems inherent in designing research and getting it funded.
In a 2015 letter to the journal Science, a group of researchers wrote that sex considerations added an additional investigational layer to research, one that was often irrelevant to the purpose of a research project. They asserted that, "nonhypothesis-driven documentation of sex differences in basic laboratory research is more likely to introduce conceptual and empirical problems in research on sex and gender than bring new clarity to differences in men's and women's health outcomes."
The writers also suggested that sex may be less of a biological variable than gender and weight. If, for example, women are more likely to be taking multiple pharmaceuticals than men and tend to be lighter in weight, these factors may be more influential on experiment outcomes than sex. Reluctant to commit to considering sex as a variable, they suggested instead two generalized studies to determine if it should be, writing, "we see a stronger empirical basis for directed funding initiatives in two areas: scientific validation of preclinical models for studying human sex differences, and human studies of the interaction of sex- and gender-related variables in producing health outcomes that vary by sex."
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A 2019 analysis by Harvard University's GenderSci Lab found that basic science researchers, "repeated again and again that their experiments were in large part constrained by practicalities of various sorts. These practicalities were often used to explain why they don't or can't account for sex in their research," says the lab's Annika Gompers. Among the practicalities noted were the acquisition of study materials such as cells from deceased patients, test animals, fat from cosmetic surgery patients, and so on. Gompers said researchers often simply work with what they can get.
She adds, "While my participants recognize that considering sex can be important for the generalizability of results, in practice it is often impractical if not impossible to incorporate sex as a variable into biomedical research. Such a finding is consistent with scholars who have long looked at science as practice and observed how practicalities — as mundane as the availability of materials — are often central to the reduction of complexity into 'doable problems.'"
As far as sample composition goes, the choice of subjects may have to do with researchers wanting to avoid the constraints and costs of the safety regulations that accompany studies of pregnant women, women of child-bearing age whom may become pregnant, children, and the elderly.
Finally, though it may be that having enough females in a sample to draw valid conclusions would likely require larger participant cohorts. Woitowich's co-author, Smith College's Anneliese Beery, says that fears of doubled sample sizes are overblown, asserting that such increases in participant numbers would be "not actually necessary."
Avoiding wasted research opportunities
One of the authors of that Science letter was Harvard's Sarah S. Richardson, who suggests a sort of middle path, though it does give researchers license to ignore the NIH requirement as they see fit. Richardson proposes something she calls "sex contextualism," which is the "simple view that the definition of sex and sex-related variables, and whether they are relevant in biological research, depends on the research context."
Science journalist Angela Saini agrees , saying, "While it's valuable to include a broad spectrum of people in studies, it doesn't necessarily follow that the sex differences will be significant or important. So disaggregating for sex, while useful sometimes, doesn't always matter."
The above points, however, don't seem to acknowledge the potential for findings important specifically to female health, and seem more concerned with protecting the efficacy of studies that benefit males.
In any event, Woitowich finds that things are progressing more slowly than the NIH and others may have hoped. While Beery says it's "exciting to see increased inclusion of female subjects across so many different fields of biology," there are potentially meaningful scientific insights being lost. The disinclination toward fully collecting and analyzing female data for research experiments "means we are still missing out on the opportunity to understand when there are sex differences and losing statistical power when sex differences go unnoticed."
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University of Utah research finds that men are especially well suited for fisticuffs.
- With males having more upper-body mass than women, a study looks to find the reason.
- The study is based on the assumption that men have been fighters for so long that evolution has selected those best-equipped for the task.
- If men fought other men, winners would have survived and reproduced, losers not so much.
Built for mayhem<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjY2NDIyMy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxMzk4NTQ2OX0.my6nML12F3fEQu3H4G0BScdqgaMZkRQHxgyj-Cmjmzk/img.jpg?width=980" id="906fc" class="rm-shortcode" data-rm-shortcode-id="dd77af7a881631355ed8972437846394" data-rm-shortcode-name="rebelmouse-image" />
Image source: Ollyy/Shutterstock<p>The researchers are, of course, talking averages here, not stating a rule: There are plenty of accomplished female pugilists, as well as lots of males who have no idea how to throw a punch.</p><p>Even so, says co-author <a href="https://www.wofford.edu/academics/majors-and-programs/biology/faculty-and-staff" target="_blank">Jeremy Morris</a> says, "The general approach to understanding why sexual dimorphism evolves is to measure the actual differences in the muscles or the skeletons of males and females of a given species, and then look at the behaviors that might be driving those differences."</p><p>Carrier has been interested in the idea that millennia of male fighting has shaped certain structures in male bodies. Previous research has reinforced his hunch:</p> <ul> <li><a href="https://jeb.biologists.org/content/216/2/236" target="_blank">When a hand is formed into a fist, its structure is self-protective</a>.</li> <li><a href="https://unews.utah.edu/flat-footed-fighters/" target="_blank">Heels planted firmly on the ground augment upper-body power</a>.</li> <li><a href="https://www.ncbi.nlm.nih.gov/pubmed/24909544" target="_blank">A study examined facial bone structure as being especially well-suited for taking a punch</a>.</li> </ul> <p>(That last one is our favorite. Do you know the German word "<a href="https://www.urbandictionary.com/define.php?term=Backpfeifengesicht" target="_blank">backpfeifengesicht</a>?" It's an adjective describing "a face that badly needs a punching.")</p><p>"One of the predictions that comes out of those," asserts Carrier, "is if we are specialized for punching, you might expect males to be particularly strong in the muscles that are associated with throwing a punch."</p>
Testing the theory<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjY2NDIzMy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYwNzMxMTE2MH0.UXJICMy57UPYUWskhK98alctOrPidJL9yxMkz3HDQrM/img.jpg?width=980" id="98718" class="rm-shortcode" data-rm-shortcode-id="b12287684ac3e740b70392e6433a6b8f" data-rm-shortcode-name="rebelmouse-image" />
Image source: Ollyy/Shutterstock<p>The researchers measured the punching — and spear-throwing — force of 20 men and 19 women. The assumption was that early humans were punchers <em>and</em> spear-throwers.</p><p>Prior to testing, each participant had filled out an activity questionnaire so that "we weren't getting couch potatoes, we were getting people that were very fit and active," says Morris.</p><p>For punching, participants operated a hand crank that required movement similar to throwing a haymaker. The purpose of the hand crank was to spare participants any damage that might be inflicted on their fists by throwing actual punches. Subjects were also measured pulling a line forward over their heads to assess their strength at throwing a spear.</p><p>Even though all of the participants, male and female, were routinely fit, the average power of males was assessed as being 162% greater than females. There were no gender differences in throwing strength recorded. Other untested, though presumably likely, hand-to-hand combat activities come to mind including tackling, clubbing, running, kicking, scratching, and biting.</p><p>Carrier's takeaway: "This is a dramatic example of sexual dimorphism that's consistent with males becoming more specialized for fighting, and males fighting in a particular way, which is throwing punches."</p>
Boys will be boys<p>It, er, strikes us as odd that, even in science fiction — hi-tech weaponry notwithstanding — the hero <em>is</em> going to wind up duking it out with some bad guy, or alien, in the climactic battle. What is it about men punching, anyway? Are they more sexually attractive? The study suggests so:</p><p style="margin-left: 20px;"><em>The results of this study add to a set of recently identified characters indicating that sexual selection on male aggressive performance has played a role in the evolution of the human musculoskeletal system and the evolution of sexual dimorphism in hominins.</em></p><p>It's tough to contribute to the gene pool after being killed in battle.</p><p>Also, while the authors aren't <em>quite</em> saying that males' historical fighting role is mandated by biology and not by social expectations, neither are they quite <em>not</em> saying it.</p><p>As Carrier explain to <a href="https://attheu.utah.edu/facultystaff/carrier-punch/" target="_blank">theU</a>: "Human nature is also characterized by avoiding violence and finding ways to be cooperative and work together, to have empathy, to care for each other, right? There are two sides to who we are as a species. If our goal is to minimize all forms of violence in the future, then understanding our tendencies and what our nature really is, is going to help."</p>
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