Sign up for our daily briefing

Make your busy days simpler with Axios AM/PM. Catch up on what's new and why it matters in just 5 minutes.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on the day's biggest business stories

Subscribe to Axios Closer for insights into the day’s business news and trends and why they matter

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sign up for Axios Pro Rata

Dive into the world of dealmakers across VC, PE and M&A with Axios Pro Rata. Delivered daily to your inbox by Dan Primack and Kia Kokalitcheva.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sports news worthy of your time

Binge on the stats and stories that drive the sports world with Axios Sports. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Tech news worthy of your time

Get our smart take on technology from the Valley and D.C. with Axios Login. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Get the inside stories

Get an insider's guide to the new White House with Axios Sneak Peek. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Denver news?

Get a daily digest of the most important stories affecting your hometown with Axios Denver

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Des Moines news?

Get a daily digest of the most important stories affecting your hometown with Axios Des Moines

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Twin Cities news?

Get a daily digest of the most important stories affecting your hometown with Axios Twin Cities

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Tampa Bay news?

Get a daily digest of the most important stories affecting your hometown with Axios Tampa Bay

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Charlotte news?

Get a daily digest of the most important stories affecting your hometown with Axios Charlotte

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Nashville news?

Get a daily digest of the most important stories affecting your hometown with the Axios Nashville newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Columbus news?

Get a daily digest of the most important stories affecting your hometown with the Axios Columbus newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Dallas news?

Get a daily digest of the most important stories affecting your hometown with the Axios Dallas newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Austin news?

Get a daily digest of the most important stories affecting your hometown with the Axios Austin newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Atlanta news?

Get a daily digest of the most important stories affecting your hometown with the Axios Atlanta newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Philadelphia news?

Get a daily digest of the most important stories affecting your hometown with the Axios Philadelphia newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Chicago news?

Get a daily digest of the most important stories affecting your hometown with the Axios Chicago newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sign up for Axios NW Arkansas

Stay up-to-date on the most important and interesting stories affecting NW Arkansas, authored by local reporters

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top DC news?

Get a daily digest of the most important stories affecting your hometown with the Axios DC newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

A bat with a GPS tag on its back. Photo: Teague O'Mara/Southeastern Louisiana University

European free-tailed bats can surf uplifting winds to fly a mile high.

Why it matters: The small mammals can achieve such heights — and high speeds sometimes of up to 84 mph — without expending a large amount of energy. Harnessing those principles could help to improve drones and other high-speed, low-energy modes of flight.

Background: Researchers had detected bats high in the sky before, but it wasn't clear to them how the bats managed to fly there.

  • Unlike herons or eagles whose wings structure allows them to soar, bats' hands — with skin stretched out over their fingers — are their wings, says Teague O'Mara, who studies bats at Southeastern Louisiana University.

What they found: O'Mara and his colleagues put GPS trackers on the backs of eight European free-tailed bats (Tadarida teniotis) to track their location. They then combined that data with topography, wind and weather models to see when and where the bats were flying with and against the wind.

  • If wind is traveling across a landscape and hits a mountain or hill, it pushes the wind straight up.
  • They saw that the bats were able to repeatedly find and ride those winds, sometimes nearly a mile up in just 20 minutes. The bats would then descend and rise again on a rollercoaster-like path, the researchers report today in the journal Current Biology.
  • "That’s super incredible," says O'Mara, in part because they don't have the long-distance visibility that birds flying during the day do and instead navigate mainly on echolocation, which has a range of about 50 meters (164 feet).
  • The findings suggest the bats have some type of mental map of the terrain, says O'Mara.
  • How bats create that map is an open question.

The big picture: "There are so many different ways animals fly that we are still discovering parts about it," says O'Mara. "Things that we thought weren't possible appear in our faces. There is such an enormous amount of variation in life."

Go deeper

5 hours ago - Health

Fauci: Omicron variant will "inevitably" be found in U.S.

Photo: Chip Somodevilla/Getty Images

Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, cautioned on Sunday that the COVID-19 Omicron variant will "inevitably" be found in the United States.

Driving the news: Fauci, Biden's chief medical adviser, told ABC's George Stephanopoulos on "This Week" that U.S. officials will meet with colleagues from South Africa later on Sunday to try to determine the severity of the cases, as countries scramble to learn more about the variant.

Updated 7 hours ago - Politics & Policy

Dems fear supply-chain blame

Illustration: Aïda Amer/Axios

As supply-chain kinks drive up prices and disrupt holiday shopping, Democrats are scrambling to show action and deflect blame.

Why it matters: With their party controlling both the White House and Capitol, vulnerable Democrats worry supply-chain snafus will hurt them in next year's midterms.

7 hours ago - World

Scoop: Germany urges Congress not to sanction Putin’s pipeline

Photo: Mikhail Svetlov/Getty Images

The German government has urged members of Congress not to sanction the Nord Stream 2 pipeline, arguing that doing so will "weaken" U.S. credibility and "ultimately damage transatlantic unity," according to documents obtained by Axios.

Why it matters: At a time when roughly 100,000 Russian troops are massing at its border, Ukraine views Nord Stream 2 as an existential threat to its security. The pipeline would circumvent Ukrainian transit infrastructure and deliver Russian gas directly to Germany, eliminating one of the last deterrents Ukraine has against an invasion.