Dec 9, 2020 - Science

Human-made materials could now outweigh all life on Earth

Plastic bags wrap around trees along the Sindh River in India.
Plastic bags wrap around trees along the Sindh River in India. Photo: Idrees Abbas/SOPA Images/LightRocket via Getty Images

For the first time in history, human-made materials now likely outweigh all life on Earth.

Why it matters: If true, it would mean the world had reached a crossover point where humankind's total footprint is heavier than the combined mass of natural life — and there's little indication that trend will change anytime soon.

Driving the news: In a paper published on Wednesday in Nature, researchers calculated the weight of roads, buildings and just about everything else humans manufacture currently to be about 1.1 trillion tons.

  • Living biomass like plants and animals comes in at approximately 1 trillion tons.
  • And while the weight of human-made materials is doubling every 20 years, the weight of living biomass has halved since the dawn of the agricultural revolution 10,000 years ago.
  • The researchers calculated human-made materials were just 3% of the weight of living biomass at the start of the 20th century.

What they're saying: "Some people think that humanity is just one species out of many, and that we’re tiny and the world is huge," Ron Milo, a researcher at the Weizmann Institute of Science and a lead author on the paper, told TIME.

  • "But our impact is not tiny."

Be smart: The paper's results provide one more piece of evidence that the planet has entered what scientists call the Anthropocene.

  • That means human beings, more than any other species or natural process, are by far the dominant power on the planet.

The bottom line: As Spiderman's Uncle Ben could tell you, with great power comes great responsibility. It's up to humanity to use that power more wisely than we have in the past — if we want a future at all.

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