Roy Niswanger / Flickr

A well-timed cold snap has let Harvard scientists capture rapid evolution in close to real time. They have measured changes in the DNA, gene expression, and cold tolerance of a species of Anole lizard, which ranges from the Texan desert to Oklahoma and North Carolina.

Why it matters: This study, published Thursday in Science, shows that extreme weather events can noticeably change a population in as little as one generation. As the climate continues to change, extreme weather events like this one will become more common. It's important to understand how species will respond — both on the organismal level and population level, and the genetic level.

Charles Brown, a behavioral ecologist who was not involved in the study, told Science the research was "one of the only real examples in which the genetic mechanisms behind these rapid evolutionary events have been shown."

This sort of intimate look at natural selection in action is rare: In this case, it was only possible because the researchers had just finished cataloguing genes, gene-expression, and cold tolerance of five groups of anole lizards over a range of 800 miles. He wanted to know what adaptations allowed them to survive in such diverse temperatures. After the massive cold snap killed off many Anole lizards, the researchers went back to document changes.

What they found: The second time the researchers looked at the anole lizards, the southernmost populations had changed significantly. They were more coordinated in cold weather, and their active genes more closely resembled the genes of the Northern, cold-hardy populations.

This doesn't mean lizards won't be harmed by climate change, cautioned Shane Campbell-Staton, an author of the study, in a statement. "Selection always comes at a cost, which is death, basically," he points out. It's possible that the genes to survive something like a heat wave died off with some of the lizards in the cold snap.

Go deeper

Updated 1 hour ago - Politics & Policy

Coronavirus dashboard

Illustration: Aïda Amer/Axios

  1. Global: Total confirmed cases as of 9 p.m. ET: 20,755,406 — Total deaths: 752,225— Total recoveries: 12,917,934Map.
  2. U.S.: Total confirmed cases as of 9 p.m. ET: 5,246,760 — Total deaths: 167,052 — Total recoveries: 1,774,648 — Total tests: 64,831,306Map.
  3. Politics: House Democrats to investigate scientist leading "Operation Warp Speed" vaccine projectMcConnell announces Senate will not hold votes until Sept. 8 unless stimulus deal is reached.
  4. 2020: Biden calls for 3-month national mask mandateBiden and Harris to receive coronavirus briefings 4 times a week.
  5. States: Georgia Gov. Brian Kemp to drop lawsuit over Atlanta's mask mandate.
  6. Business: Why the CARES Act makes 2020 the best year for companies to lose money.
  7. Public health: Fauci's guidance on pre-vaccine coronavirus treatments Cases are falling, but don't get too comfortable.

Trump says he intends to give RNC speech on White House lawn

President Trump speaking to reporters on South Lawn in July. Photo: Jabin Botsford/The Washington Post via Getty Images

President Trump told the New York Post on Thursday that he plans to deliver his Republican National Convention speech from the White House lawn, despite bipartisan criticism of the optics and legality of the location.

Why it matters: Previous presidents avoided blurring staged campaign-style events — like party conventions — with official business of governing on the White House premises, per Politico.

Fauci's guidance on pre-vaccine coronavirus treatments

Illustration: Aïda Amer/Axios

Antibody drugs and various medicine cocktails against the coronavirus are progressing and may provide some relief before vaccines.

The big picture: Everyone wants to know how and when they can return to "normal" life, as vaccines are not expected to be ready for most Americans for at least a year. Two therapies are known to be helpful, and more could be announced by late September, NIAID Director Anthony Fauci tells Axios.