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How Much Does Humanity Weigh?

2022-11-18 · explainer · Hank · 3:59 · watch on YouTube

Topic: Science & nature · mode: Explainer · tags: timely hook, self promotion

Hank explains mammal biomass: humans are about a third of it, cows another third, other livestock 30% and wild mammals 4%, after a megafauna extinction and agriculture cut wild mammal biomass 85% while total mammal biomass rose 800%; he calls that bad but complex and urges doing it thoughtfully.

What is said

The parts of the video and what is said in each (★ — how much it matters to the video).

00:00:00 — Hook; living matter, water and counting carbon: biomass

  • ★ Hank says he has about 90,000 grams of living matter, but most of it is water, which life needs but which isn't really part of the living system. — 00:00:00
  • ★★ Hank says scientists count just the carbon in living matter, which he thinks is a good, precise-enough method; this is called biomass. — 00:00:29
  • ★★★ Hank says of all mammal biomass about a third is humans, another third cows, a further 30% other agricultural animals, and only 4% wild mammals. — 00:00:29

00:00:52 — Today's mammal biomass split and its history: the Quaternary megafauna extinction and agriculture

  • ★★★ Hank says wild mammal biomass was stable at its peak 100,000 years ago, when humans were insignificant, then dropped by about 25% by 10,000 years ago: the Quaternary megafauna extinction, mostly of very large mammals. — 00:01:37
  • ★★ Hank says the extinction is much debated, but humans definitely contributed: it coincided closely with humans' arrival in North and South America and, separately, Australia. — 00:02:06 · Australia
  • ★★★ Hank says that between 10,000 and 100 years ago, with agriculture, wild mammal biomass fell by a further third while total mammal biomass rose beyond any earlier level, purely because of humans and livestock. — 00:02:06

00:02:35 — Humans outweigh all pre-human mammals; bad but complex; the 8 billionth person; doing it thoughtfully

  • ★★★ Hank says humans alone now have three times the biomass of all mammals before humans; over 100,000 years wild mammal biomass fell 85% and total mammal biomass rose 800%. — 00:02:35
  • ★★★ Having tried not to judge, Hank concludes it is bad to have an 85% decrease in wild mammal biomass. — 00:02:35
  • ★★ Hank adds that it is also very complex: Earth is at its historical maximum of complicated brains. — 00:03:05
  • ★★ Hank notes that a few days ago a baby was born who was the 8 billionth person on the planet. — 00:03:05
  • ★★★ Hank says he doesn't really know what to say except that we need to do all this thoughtfully, because it is a very big and fast change. — 00:03:05
  • ★★ Hank thinks one can make the case that we are doing it more thoughtfully now than 100 years ago. (hedged) — 00:03:05

00:03:31 — Coffee club farmers and deforestation; the sock club closes Monday; sign-off

  • ★★ Hank says coffee plantations can drive deforestation but can be done in partnership with a forest; the Awesome Coffee Club's small farmers work to reduce deforestation and practise regenerative agriculture. — 00:03:34 · Awesome Coffee Club
  • ★★★ Hank says the Sock Club closes Monday and there will be no other Vlogbrothers video before then, so viewers who want to sign up must do it now. — 00:03:34 · Awesome Socks Club, Vlogbrothers
  • ★ Hank says the Coffee Club will remain open perpetually. — 00:03:34 · Awesome Coffee Club

In the description and comments

  • ★★ The description adds that mammals are just 7% of animals, animals are less than one percent of Earth's biomass, and plants make up more than 80% of it: we live in the age of plants. — video description
  • ★★ In a channel comment John points out that almost all of Earth's biomass is not humans, cattle or any mammals but bacteria and insects. — creator comment
  • ★ In a comment reply Hank says fully half of wild mammal biomass is whales and dolphins. — creator comment

Threads in this video

Where the stories that moved here went next

Mentioned

Central: Biomass (ecology)

Also: Projects: Awesome Coffee Club · Awesome Socks Club

Concepts: agriculture · carbon · Cattle · deforestation · human impact on the environment · Quaternary extinction event

Places: Australia · North America · South America

fact: world population

Only in the description or credits: Bacteria · dolphin

Also centred on Biomass (ecology): The Weight of Life

Later videos replying to this one

  • 2022-11-29 · The Weight of Life (John) — continues — “You recently made a video about the overall biomass of humans” (00:00:00)