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Antillean Crescent (Antillea pelops) butterfly at El Yunque National Forest

Antillean Crescent (Antillea pelops) butterfly at El Yunque National Forest. (Getty)

Insects are disappearing globally

Arthropod populations are crashing in Puerto Rico’s lush, protected Luquillo rainforest, along with the lizards, frogs and birds that eat them. Researchers found that the biomass of insects and other arthropods trapped in sticky ground traps in 2013 was 60 times less than that in 1976. The study echoes recent alarming results in Germany and globally. “This study in PNAS is a real wake-up call — a clarion call — that the phenomenon could be much, much bigger, and across many more ecosystems,” says entomologist David Wagner. “This is one of the most disturbing articles I have ever read.”

The Washington Post | 6 min read

Reference: PNAS paper

All systems go for second mission to Mercury

This Friday, if all goes according to plan, BepiColombo will begin its journey to becoming only the second spacecraft to orbit Mercury. The US$1.85-billion expedition, carrying two robotic orbiters, ranks among the most expensive missions undertaken by the European Space Agency, and it includes Japan’s largest contribution yet to an international collaboration in space. To reach Mercury, deep in the Sun’s gravitational well, BepiColombo will use advanced, solar-powered ionic thrusters combined with gravitational assists from a total of nine fly-bys of Earth, Venus and Mercury itself.

Nature | 6 min read

BepiColombo will probe Mercury’s chemistry, geology and magnetosphere.

Climate change could double your bar tab

More-frequent droughts and heat waves caused by climate change will reduce global barley production by up to 17%. The effect of that will be a drop in beer supply that could roughly double, on average, the cost of your ale. Beer production might seem like a trivial consideration when it comes to climate change, but the researchers want people to think about the broad implications of global warming. "What I’m trying to emphasize here is that climate change will impact people’s lifestyle,” says climate-change economist Dabo Guan.

Nature | 4 min read

Reference: Nature Plants paper

Astronomy is losing women faster than men

An analysis of faculty hiring data shows that female astronomers in the United States are leaving academia at a rate three to four times higher than their male counterparts. The results confirms anecdotal reports of this phenomenon. The study also showed that women are hired, on average, a year earlier than men. Models show that this gap is most likely explained by the higher rate of women leaving: those who remain are overrepresented in the data and the average time for the women who do get hired gets shorter.

Nature | 4 min read

Reference: arXiv preprint

FEATURES & OPINION

“I needed to be on the right side of history”

Cancer researcher Ashani Weeraratna moved to the United States in 1988 because she saw it as a beacon of diversity compared with her options in apartheid-era South Africa — but she has faced harassment in her new country. She explores how she came to speak at a rally about the effects of current US immigration policies on biomedical science. “I tried not to let it bother me back then,” she says. “It’s different now, though, because I have a biracial daughter to protect.”

Nature | 4 min read

The spacecraft sniffer

George Aldrich has spent 45 years on NASA’s volunteer panel of 25 people whose job is to smell items before they are sent into space. After getting a job at the White Sands Test Facility in New Mexico straight out of high school, Aldrich joined the sniffers because “it was a great thing to do for the astronauts”, who could be affected by foul or overwhelming smells in the closed environment of a spacecraft.

Chemistry World | 6 min read

DNA and Native American identity

US Senator Elizabeth Warren announced this week that a genetic test revealed she has some Native American ancestry. The news has raised questions about what such DNA results actually mean, writes geneticist Jennifer Raff, who specializes in Native American population history. “A DNA test is useless to determine tribal citizenship. Current DNA tests do not even distinguish whether a person’s ancestors were indigenous to North or South America,” says Cherokee Nation Secretary of State Chuck Hoskin, Jr.

Warren has stressed that she is not laying claim to membership of a tribal nation and does not identify as Native American, but she has shared a family story that her ancestor was Cherokee, leading to criticisms from the Cherokee Nation and Indigenous scholars. “They know darn well that the broader US public will take a DNA test to be a true indication of her right to claim Native American identity in some way,” says Native Studies researcher Kim TallBear.

Forbes & Indian Country Today | Both 5 min reads

QUOTE OF THE DAY

QUOTE OF THE DAY

“We wanted to build it for the big one. We just never knew we’d find the big one so fast.”

The storm-resistant beach house that radiologist Lebron Lackey and his uncle built now stands alone among the rubble of its neighbours after Hurricane Michael struck Florida. (The New York Times)