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Human Race Just 0.01% of All Life But Has Destroyed 83% of Wild Mammals, Study Finds (theguardian.com)

An assessment of all life on Earth has revealed humanity's surprisingly tiny part in it as well as our disproportionate impact. From a report: The world's 7.6 billion people represent just 0.01% of all living things, according to the study. Yet since the dawn of civilisation, humanity has caused the loss of 83% of all wild mammals and half of plants, while livestock kept by humans abounds. The new work is the first comprehensive estimate of the weight of every class of living creature and overturns some long-held assumptions. Bacteria are indeed a major life form -- 13% of everything -- but plants overshadow everything, representing 82% of all living matter. All other creatures, from insects to fungi, to fish and animals, make up just 5% of the world's biomass.

Another surprise is that the teeming life revealed in the oceans by the recent BBC television series Blue Planet II turns out to represent just 1% of all biomass. The vast majority of life is land-based and a large chunk -- an eighth -- is bacteria buried deep below the surface. "I was shocked to find there wasn't already a comprehensive, holistic estimate of all the different components of biomass," said Prof Ron Milo, at the Weizmann Institute of Science in Israel, who led the work, published in the Proceedings of the National Academy of Sciences.

10 of 192 comments (clear)

  1. humans have 2 legs. dogs have 5 million follicles by Anonymous Coward · · Score: 4, Insightful

    are we just quantifying random stuff and telling the world about it?

    0.01% of life by weight is currently humans, but we've killed 83% of mammal species... by species count? individuals?
    what percentage of mammal species does humanity account for? by weight or by head count?
    what about other groups? insects? viruses? reptiles? haven't we hunted any fish into the same category as the dodo?

    how many species did t-rex hunt to extinction? what counts as a species?

    seriously. get your s*** together, researchers. get it all together in one place.

  2. Re:We are a plague. by Pinky's+Brain · · Score: 3, Insightful

    There are no innocents without a concept of morality. They can resume eating each other alive without any concept of innocence or guilt without disturbance by man at some point, until that time we are the apex predator.

    We generally treat our cattle nicer than do the lesser predators.

  3. Re:I kill a moose a year to feed my family. by Oligonicella · · Score: 5, Informative

    How much of that Moose do you use to feed your family.(?)

    If it's like with deer around here, almost all of it. Steaks, burger and sausage. Bones and offal for the dogs. Hide sold for leather and antlers have various uses. Not much left.

    Don't project your cultural norms onto others.

  4. Thanos had a point by imperious_rex · · Score: 3, Interesting

    He may be a nihilistic Malthusian, but Thanos had a valid point. If one could eliminate 50% of sentient life from a world, the long term benefits would outweigh the immediate negatives. This is already based on historical precedence. After the Black Plague wiped out over 1/3 of Europe's population, the continent experienced a rebirth that became the Renaissance, the church lost much of its power, the continent's economic power strength improved, and the age of the Enlightenment came about which brought new artistic, scientific, and political thinking. One has to wonder what the long term impact would be from reducing the Earth's current human population from 7.6 billion to 3.8 billion (approximately 1970's world population).

    1. Re:Thanos had a point by PPH · · Score: 3, Interesting

      We don't have to kill randomly. In fact, we can leave it up to each group to select those that shall die.

      We, in the West, will not kill so many. We will invite them across our borders because the economy in their country is somewhat worse off than ours. Meanwhile, when ocean levels rise and farmers in Bangladesh are forced inland 20 miles to escape flooding, their neighbors will slaughter them. Problem solved.

      --
      Have gnu, will travel.
  5. Re:Lets convert Meters to Galons. by jedidiah · · Score: 4, Insightful

    Real science doesn't come with a political agenda.

    Politics is as distinct from science as religion is. People with an agenda are just abusing statistics.

    Continue these delusions of yours at your peril.

    --
    A Pirate and a Puritan look the same on a balance sheet.
  6. Re:humans have 2 legs. dogs have 5 million follicl by dinfinity · · Score: 3, Informative

    0.01% of life by weight is currently humans, but we've killed 83% of mammal species... by species count? individuals?

    Individuals. RTFA.

    what percentage of mammal species does humanity account for? by weight or by head count?

    36%, by head count. RTFA.

    what about other groups? insects? viruses? reptiles?

    They 'measured' marine mammals (80%), plants (50%), fish (15%). RTFA.

    Get your shit together, AC. Get it all together and put it in a backpack.

  7. Obligatory XKCD by Paul+Fernhout · · Score: 4, Informative

    Earth's Land Mammals by Weight: https://xkcd.com/1338/

    Explained: https://www.explainxkcd.com/wi...

    It references a 2002 book: "The Earth's Biosphere: Evolution, Dynamics, and Change".

    So, while this topic is very important, I'm not sure what in the study is actually "news"? Maybe the low percentage of ocean biomass (which I feel is hard to believe)?

    --
    A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
  8. Re:omnivore by Applehu+Akbar · · Score: 3, Interesting

    If we put our mind (and stomach) to it, we can eat anything into extinction.

    Actually it's the other way around. We have found that the most effective way to save a declining species is to start eating it:
    https://www.dartagnan.com/buy/...

  9. Re:humans have 2 legs. dogs have 5 million follicl by careysub · · Score: 4, Informative

    0.01% of life by weight is currently humans, but we've killed 83% of mammal species... by species count? individuals?

    Individuals. RTFA.

    Says a guy who didn't read the actual paper and is guessing?

    That percentage was calculated from this line in the actual (not made-up) report:

    The Report:
    "Human activity contributed to the Quaternary Megafauna Extinction between 50,000 and 3,000 y ago, which claimed around half of the large (>40 kg) land mammal species (30). The biomass of wild land mammals before this period of extinction was estimated by Barnosky (30) at 0.02 Gt C. The present-day biomass of wild land mammals is approximately sevenfold lower, at 0.003 Gt C."

    100*(1 - 0.003/0.02) = 85%, not exactly the 83% quoted but within the accuracy of the estimate.

    what percentage of mammal species does humanity account for? by weight or by head count?

    36%, by head count. RTFA.

    The paper is entirely done with biomass estimates. Why are you BSing everyone?

    --
    Starships were meant to fly, Hands up and touch the sky - Nicky Minaj