Data: 'Global plate boundary evolution and kinematics since the late Paleozoic'; Map: Lazaro Gamio / Axios

The breakup of supercontinents over the last 443 million years is responsible for the richness of global marine life, researchers show in a new study. In fact, a "significant component" of marine animal diversity is due to the creation and then separation of just one supercontinent – Pangaea - more than 175 million years ago.

What it tells us: Biologists have wondered for decades why the animal world is so diverse across the planet. They began to hypothesize in the 1970s that plate tectonics causing shifts in the continental crust were probably responsible for the global dispersal of species. But, at the time, they had no way to prove that biodiversity grew when supercontinents split apart.

How they cracked the case: Researchers used global marine fossil data and matched it up against continental configurations and reconstructed paleographic records. As supercontinents split apart, the fossil record shows a much greater richness among various forms of marine life.

  • Marine life = bivalves like clams, trilobites — some of the earliest animals with an exoskeleton, extinct marine mollusks known as ammonoids, primitive nautilus and other invertebrate animals

How it works: Animals evolve under pressure, especially from their environment. When a supercontinent breaks up, marine animals connected to each land mass are carried to other parts of the world like passengers on a ship. Species adapt in a multitude of ways to their new environment, contributing to diversity.

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Updated 10 mins ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 11:30 p.m. ET: 31,478,387 — Total deaths: 968,726 Total recoveries: 21,622,862Map.
  2. U.S.: Total confirmed cases as of 11:30 p.m. ET: 6,895,685 — Total deaths: 200,768 — Total recoveries: 2,646,959 — Total tests: 96,612,436Map.
  3. Health: The U.S. reaches 200,000 coronavirus deaths — The CDC's crumbling reputation — America turns against coronavirus vaccine.
  4. Politics: Elected officials are failing us on much-needed stimulus.
  5. Business: Two-thirds of business leaders think pandemic will lead to permanent changes — Fed chair warns economy will feel the weight of expired stimulus.
  6. Sports: NFL fines maskless coaches.

Trump pushes to expand ban against anti-racism training to federal contractors

Trump speaking at Moon Township, Penns., on Sept. 22. Photo: Mandel Ngan/AFP via Getty Images

President Trump announced late Tuesday that the White House attempt to halt federal agencies' anti-racism training would be expanded to block federal contractors from "promoting radical ideologies that divide Americans by race or sex."

Why it matters: The executive order appears to give the government the ability to cancel contracts if anti-racist or diversity trainings focused on sexual identity or gender are organized. The memo applies to executive departments and agencies, the U.S. military, federal contractors and federal grant recipients.

Dan Primack, author of Pro Rata
4 hours ago - Economy & Business

GoodRx prices IPO at $33 per share, valued at $12.7 billion

Illustration: Sarah Grillo/Axios

GoodRx, a price comparison app for prescription drugs at local pharmacies, on Tuesday night raised $1.14 billion in its IPO, Axios has learned.

By the numbers: GoodRx priced its shares at $33 a piece, above its $24-$28 per share offering range, which will give it an initial market cap of around $12.7 billion.

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