Two colonies of different species of pediastrum green algae Photo: Sally Warring / Pondlife

The majority of life on Earth can't be seen with the naked eye. Bacteria, amoeba, archaea found on hydrothermal vents, single-celled algae, and other unicellular organisms outnumber us multicellular types and have existed on the planet at least 2 billion years longer. Some, like the green algae pediastrum shown above, form colonies from identical cells, each self-sufficient despite their communing.

History lesson: Some of these early occupiers of Earth eventually joined together to share the work of life and cooperate to survive — a key step in life's evolution on Earth (and one that could also inform the search for alien life beyond the planet).

Go deeper: Biologist Sally Warring collects samples of unicellular organisms from New York City's ponds and documents the extraordinary lives of single cells at Pondlife.

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Updated 23 mins ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 9:30 p.m. ET: 33,867,247 — Total deaths: 1,012,341 — Total recoveries: 23,537,059Map.
  2. U.S.: Total confirmed cases as of 8 p.m. ET: 7,229,319 — Total deaths: 206,887 — Total recoveries: 2,840,688 — Total tests: 103,939,667Map.
  3. Education: School-aged children now make up 10% of all U.S COVID-19 cases.
  4. Health: The coronavirus' alarming impact on the body.
  5. Business: Real-time data show economy's rebound slowing but still going.
  6. Sports: Steelers-Titans NFL game delayed after coronavirus outbreak.
Ina Fried, author of Login
54 mins ago - Technology

Facebook removes Trump ads tying refugees to COVID-19

Photo Illustration: Aïda Amer/Axios. Photo: Saul Loeb/AFP via Getty Images

Facebook said Wednesday that it was removing a series of ads from President Trump's campaign that linked American acceptance of refugees with increased coronavirus risk, a connection Facebook says is without merit.

Why it matters: The ads were pulled after they received thousands of impressions and are a sign that the Trump campaign continues to test the limits of social media rules on false information.

Over 73 million people watched the first debate on TV

Data: Nielsen; Chart: Andrew Witherspoon/Axios

More than 73.1 million people watched the first presidential debate on television on Tuesday night, according to Nielsen ratings.

Why it matters: While that's a sizable audience for any American TV program, it's down more than 13% from the record number of TV viewers who tuned in for the first debate of the 2016 election. The chaotic nature of the debate and the overall uncertainty around this year's election may have pushed some viewers away.