Skip to main content Skip to navigation
CAS in the Media Arts and Sciences Media Headlines

Ask Dr. Universe: Why do we have nose hairs?

Despite being a curious science cat, I must confess I haven’t spent much time looking up human noses. But I have noticed that human nostrils can be a bit…furry.

I talked about what’s inside your nose with my friend Edward Johnson. He teaches classes about the human body in the School of Biological Sciences at Washington State University.

He told me that nose hairs only grow in your nose’s vestibule. That’s the inside of the part of your nostrils that you can flare out. The nose hair’s job is to filter the air you breathe in through your nose.

When you breathe in, air enters your nose of course. But so do other things like little bits of dust, pollen and pollution like from wildfire smoke. Sometimes bacteria and viruses are hanging out in the air you breathe, too.

Your nose hairs are like guards for the entrance to your nose.

Read the full story:
Ask Dr. Universe

Social status changes hyenas’ epigenetics

An animal’s position in hierarchical hyena packs influences her gene expression.

For a spotted hyena on the Serengeti, social status is everything. Clans adhere to a strict hierarchy of dominance among adult females. Now, a group of researchers has found social status is more than superficial; it stretches into the animals’ DNA (Commun. Biol. 2024, DOI: 10.1038/s42003-024-05926-y).

Many traditional methods for collecting DNA are too invasive for wild hyena populations, says lead researcher Alexandra Weyrich from the German Centre for Integrative Biodiversity Research, Halle-Jena-Leipzig. “So, we sample the feces.”

In collaboration with Weyrich, researchers from the Serengeti Hyena Project—who know each individual animal by sight—scooped the poop for later analysis.

“What we found is quite stunning,” says Weyrich: there is a distinct correlation between social status and DNA methylation. Adding methyl groups to certain regions of DNA changes how those regions are transcribed and can act like a genetic on/off switch.

Forty-four genes are associated with the 147 differently methylated regions they found, says Weyrich. Some of these genes regulate energy conversion and appear more methylated in low-status females. This indicates that the animals are processing energy differently than their social superiors, says Weyrich, perhaps because low-ranking hyenas are forced to travel farther for resources.

“I think the data they found was quite solid and interesting,” says Michael Skinner, an epigeneticist at Washington State University. To him, this is another study demonstrating that epigenetic processes control most biological phenomena.

Read the full story:
C&EN

 

Genes identified that allow bacteria to thrive despite toxic heavy metal in soil

Some soil bacteria can acquire sets of genes that enable them to pump the heavy metal nickel out of their systems, a study has found. This enables the bacteria to not only thrive in otherwise toxic soils but help plants grow there as well.

A Washington State University-led research team pinpointed a set of genes in wild soil bacteria that allows them to do this in serpentine soils which have naturally high concentrations of toxic nickel. The genetic discovery, detailed in the journal Proceedings of the National Academies of Sciences, could help inform future bioremediation efforts that seek to return plants to polluted soils.

“We can say with certainty that these are the genes that are letting the bacteria survive the heavy metal exposure because if we take them away, they die. If we add them to a new bacterium that was sensitive to the heavy metal, all of the sudden it’s resistant,” said Stephanie Porter, the study’s senior author and a WSU evolutionary ecologist.

Read the full story:
Phys.org
ScienceDaily
TechnologyNetworks

Meet the ice worm, one of the most mysterious creatures in the world

When Peter Wimberger of the University of Puget Sound was first told about ice worms, he thought that his colleagues were pranking him. Imagine his surprise when he learned that not only are these creatures real, they are full of mysteries that if solved, could help answer one of the biggest questions in science.

There are millions of these animals across the world and yet despite their abundance, they have barely been studied, with scientists treating them as a mere curiosity. Scott Hotaling, a glacier biologist [at Utah State University and a former postdoctoral researcher at] Washington State University, and his colleague Peter Wimberger have been studying ice worms for several years.

“There are more mysteries than there are solved things with ice worms”, says Hotaling.

Unlike humans, who lose energy when they are in a cold environment, ice worms thrive in the cold and their energy levels go up when they are subjected to low temperatures. They live comfortably at 32 degrees Fahrenheit (0 degrees Celsius), but if temperatures dip slightly below that, they die.

Read the full story:
AfricaPress

Toxicant Exposures Show Health Effects Across Generations

While exposure to a single substance like DDT has been shown to create inherited disease susceptibility, a recent study in animals found exposure to multiple different toxicants across generations can amplify those health problems.

In the study, published in the journal Environmental Epigenetics, the researchers exposed an initial generation of pregnant rats to a common fungicide, then their progeny to jet fuel, and the following generation to DDT. When those rats were then bred out to a fifth unexposed generation, the incidence of obesity as well as kidney and prostate diseases in those animals were compounded, rising by as much as 70%.

The researchers also found that their epigenetics, molecular processes independent of DNA that influence gene expression, were also greatly altered.

“We looked at multiple-generation exposures because these types of things are going on routinely, and previous research has only looked at single exposures,” says Michael Skinner, a Washington State University biology professor and the study’s corresponding author. “We found that if multiple generations get different exposures, then eventually there’s an amplification or compounded effect on some diseases.”

The study did show that for other diseases, those associated with the ovaries and the testes, the incidence rose in the first generation of progeny but appeared to plateau with the additional generational exposures.

Read the full story:
Good Men Project