CLOSE
iStock
iStock

Cockroach DNA Shows Why They're Basically Indestructible

iStock
iStock

Most people are all too aware that cockroaches are horrifyingly resilient beings. Yes, they can and have survived nuclear blasts, and surely stand to inherit the Earth after we all succumb to the apocalypse. Why is this creature able to thrive in the face of pesticides, the loss of limbs, disgusting conditions, a range of climates, and even nuclear fallout, in urban kitchens across the world? As Inside Science reports, a new study on the genome of the American cockroach shows that certain genes are key to its wild evolutionary success.

In an article published in Nature Communications, researchers from South China Normal University in Guangzhou, China report that they sequenced and analyzed the genome of Periplaneta americana, and in the process they discovered just how indestructible this scourge is. They found that the cockroach (native to Africa, despite its American moniker) has more DNA than any other insect whose DNA has been sequenced except the migratory locust. The size of its genome—3.3 billion base pairs—is comparable to that of humans.

They have a huge number of gene families (several times the number other insects have) related to sensory reception, with 154 smell receptors and 522 taste receptors, including 329 taste receptors specifically related to bitter tastes. These extra smell and taste receptors may help cockroaches avoid toxic food (say, your household pesticide) and give them the ability to adapt to a multitude of different diets in different environments.

They also have killer immune systems able to withstand pathogens they might pick up from the rotting food they eat and the filth they like to live in. They have many more genes related to immunity compared to other insects.

The genome analysis might give us more than just a newfound respect for this revolting pest. The researchers hope to find a way to harness this new knowledge of cockroach immunity to control vermin populations—and create an eradication method slightly more effective than just stomping on them.

[h/t Inside Science]

nextArticle.image_alt|e
iStock
arrow
language
The Surprising Link Between Language and Depression
iStock
iStock

Skim through the poems of Sylvia Plath, the lyrics of Kurt Cobain, or posts on an internet forum dedicated to depression, and you'll probably start to see some commonalities. That's because there's a particular way that people with clinical depression communicate, whether they're speaking or writing, and psychologists believe they now understand the link between the two.

According to a recent study published in Clinical Psychological Science, there are certain "markers" in a person's parlance that may point to symptoms of clinical depression. Researchers used automated text analysis methods to comb through large quantities of posts in 63 internet forums with more than 6400 members, searching for certain words and phrases. They also noted average sentence length, grammatical patterns, and other factors.

What researchers found was that a person's use (or overuse) of first-person pronouns can provide some insight into the state of their mental health. People with clinical depression tend to use more first-person singular pronouns, such as "I" and "me," and fewer third-person pronouns, like "they," "he," or "she." As Mohammed Al-Mosaiwi, a Ph.D. candidate in psychology at the University of Reading and the head of the study, writes in a post for IFL Science:

"This pattern of pronoun use suggests people with depression are more focused on themselves, and less connected with others. Researchers have reported that pronouns are actually more reliable in identifying depression than negative emotion words."

What remains unclear, though, is whether people who are more focused on themselves tend to depression, or if depression turns a person's focus on themselves. Perhaps unsurprisingly, people with depression also use more negative descriptors, like "lonely" and "miserable."

But, Al-Mosaiwi notes, it's hardly the most important clue when using language to assess clinical depression. Far better indicators, he says, are the presence of "absolutist words" in a person's speech or writing, such as "always," "constantly," and "completely." When overused, they tend to indicate that someone has a "black-and-white view of the world," Al-Mosaiwi says. An analysis of posts on different internet forums found that absolutist words were 50 percent more prevalent on anxiety and depression forums, and 80 percent more prevalent on suicidal ideation forums.

Researchers hope these types of classifications, supported by computerized methods, will prove more and more beneficial in a clinical setting.

[h/t IFL Science]

nextArticle.image_alt|e
Fox
arrow
Pop Culture
The ‘Scully Effect’ Is Real: Female X-Files Fans More Likely to Go Into STEM
Fox
Fox

FBI agent Dana Scully is more than just a role model for remaining professional when a colleague won't stop talking about his vast governmental conspiracy theories. The skeptical doctor played by Gillian Anderson on The X-Files helped inspire women to go into STEM (science, technology, engineering, and math) careers, according to a new report [PDF] from the Geena Davis Institute on Gender in Media, which we spotted at Fast Company.

“In the world of entertainment media, where scientists are often portrayed as white men wearing white coats and working alone in labs, Scully stood out in the 1990s as the only female STEM character in a prominent, prime-time television role,” the report explains. Previously, anecdotal evidence has pointed to the existence of a “Scully effect,” in which the measured TV scientist—with her detailed note-taking, evidence-based approach, and desire to autopsy everything—inspired women to seek out their own science careers. This report provides the hard data.

The Geena Davis Institute surveyed more than 2000 women in the U.S. above the age of 25, a significant portion of whom were viewers of The X-Files (68 percent) and women who had studied for or were in STEM careers (49 percent). While the survey didn’t ask women whether watching Dana Scully on The X-Files directly influenced their decision to be a scientist, the results hint that seeing a character like her on TV regularly did affect them. Women who watched more of the show were more likely to say they were interested in STEM, more likely to have studied a STEM field in college, and more likely to have worked in a STEM field after college.

While it’s hard to draw a direct line of causation there—women who are interested in science might just be more inclined to watch a sci-fi show like The X-Files than women who grow up to be historians—viewers also tended to say Scully gave them positive impressions of women in science. More than half of respondents who were familiar with Scully’s character said she increased their confidence in succeeding in a male-dominated profession. More than 60 percent of the respondents said she increased their belief in the importance of STEM. And when asked to describe her, they were most likely to say she was “smart” and “intelligent” before any other adjective.

STEM fields are still overwhelmingly male, and governments, nonprofits, schools, activists, and some tech companies have been pushing to make the field more diverse by recruiting and retaining more female talent. While the desire to become a doctor or an engineer isn’t the only thing keeping STEM a boy’s club, women also need more role models in the fields whose success and accomplishments they can look up to. Even if some of those role models are fictional.

Now that The X-Files has returned to Fox, perhaps Dana Scully will have an opportunity to shepherd a whole new generation of women into the sciences.

[h/t Fast Company]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios