Month: March 2020

Enlarge / A new study shows that mantis shrimp don't punch quite as powerfully when they are out of the water. (credit: Dash Shemtoob/Getty Images)

The mantis shrimp is famous in the animal kingdom for its fast, powerful hammer strike, on par with the force generated by a .22 caliber bullet. One might conclude that those strikes would be even faster and more formidable in air, given the lower density and less drag of the medium. But that's not the case, according to a recent paper in the Journal of Experimental Biology. Rather, scientists found that the animal punches at half the speed in air, suggesting that the mantis shrimp can precisely control its striking behavior, depending on the surrounding medium.

Mantis shrimp come in many different varieties: there are some 450 known species. But they can generally be grouped into two types: those that stab their prey with spear-like appendages ("spearers") and those that smash their prey ("smashers") with large, rounded, and hammer-like claws ("raptorial appendages"). Those strikes are so fast—as much as 23 meters per second, or 51mph—and powerful, they often produce cavitation bubbles in the water, creating a shock wave that can serve as a follow-up strike, stunning and sometimes killing the prey. Sometimes a strike can even produce sonoluminescence, whereby the cavitation bubbles produce a brief flash of light as they collapse.

Per a 2018 study, the secret to that powerful punch seems to arise not from bulky muscles but from the spring-loaded anatomical structure of the shrimp's arms, akin to a bow and arrow. The shrimp's muscles pull on a saddle-shaped structure in the arm, causing it to bend and store potential energy, which is released with the swinging of the club-like claw.

Enlarge (credit: Getty Images / Aurich Lawson)

Facebook is poised to shelve its own Libra cryptocurrency proposal, two media reports indicate. But Facebook says it remains committed to the project.

A new report from The Information, citing "three people familiar with the matter," says that Facebook has decided not to support the new virtual currency in its own products. Instead, Facebook will offer users the ability to make payments using conventional currencies like the dollar and the euro. The rollout of Facebook's expected digital wallet software will also be delayed by "several months," The Information reports.

Bloomberg also talked to "three people familiar with the matter" but described the situation differently. According to Bloomberg, Facebook and its partners are "weighing a recast of Libra as mostly a payments network that could operate with multiple coins."

Enlarge / Google (and now also Alphabet) CEO Sundar Pichai speaking at the last year's Google I/O conference, May 7, 2019. (credit: JOSH EDELSON | AFP | Getty Images)

Silicon Valley's spring series of tech shows continues to dwindle in the face of communicable disease: Google's I/O developer conference for 2020 has now been canceled as the company cites coronavirus concerns.

"Due to concerns around the coronavirus (COVID-19), and in accordance with health guidance from the CDC, WHO, and other health authorities, we have decided to cancel the physical Google I/O event," the company said. In lieu of bringing a whole bunch of breathing, potentially coughing people together in one place, "we will explore other ways to evolve Google I/O to best connect with our developer community," likely with a heavy focus on online delivery.

Anyone who purchased a pass to the 2020 I/O will receive a full refund by March 13, Google's website says, and all registered attendees for the 2020 show will automatically be "extended an invitation" for the 2021 edition.

Enlarge / SEATTLE, WA - FEBRUARY 29: Healthcare workers transport a patient on a stretcher into an ambulance at Life Care Center of Kirkland on February 29, 2020, in Kirkland, Washington. Dozens of staff and residents at Life Care Center of Kirkland are reportedly exhibiting coronavirus-like symptoms. (credit: Getty | David Ryder)

As ramped-up testing for COVID-19 by individual US states exposes hidden cases, disease transmission, and deaths, officials at the Centers for Disease Control and Prevention are urging citizens to do their part to stop the spread of the new virus—including taking an extended hiatus from their daily lives.

“You may need to take a break from your normal daily routine for two weeks,” Dr. Nancy Messonnier, director of the CDC’s National Center for Immunization and Respiratory Diseases, said in a briefing Tuesday.

At the time of publishing this story, there were at least 118 COVID-19 cases and nine deaths reported across at least 12 states in the US. Of those cases, 48 are in repatriated citizens, and the rest are a mix of travel-related cases, cases linked to travel cases, and community-spread cases. All of the deaths have occurred in Washington state, where the first US case was detected. Many of the cases in the state have since been linked to an outbreak in a King County skilled nursing home called Life Care.