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Lets take in mind that there is a problem to compare two groups when one group is much easier to measure than the other. The error interval in the mammal biomas

Lets take in mind that there is a problem to compare two groups when one group is much easier to measure than the other. The error interval in the mammal biomass should be much higher. The actual real values are probably not so extreme. ... I see, is just megafauna. The most competitive groups (rodents and bats) are deliberately excluded. The title is incorrect then.

deathanatos 4y ago
Certainly the article might not be credible, but can you cite the relevant text from the article, so that the rest of us can quickly verify your claim? I'm not seeing where in the article this is stated.
- pvaldes 4y ago
  whales, dolphins and seals are also excluded. > "biomass from marine mammals – mainly whales – is not included" They discuss specifically about megafauna and large terrestrial mammals in most paragraphs and figures.
  - astroalex 4y ago
    In the specific section that I took this statistic from, whales seem to be included: https://ourworldindata.org/mammals#wild-mammals-make-up-only-a-few-percent-of-the-world-s-mammals https://ourworldindata.org/mammals#wild-mammals-make-up-only...
nightpool 4y ago
Is this true? This source (https://www.pnas.org/doi/10.1073/pnas.1711842115 https://www.pnas.org/doi/10.1073/pnas.1711842115) gives a very similar percentage (95.8% of all wild mammals) and doesn't mention anything about excluding rodents or bats from the categorization of wild mammals. Is it in a footnote somewhere that I'm missing?
club_tropical 4y ago
Also, “biomass” is a strange term. Is that literally an estimate of mass? Or count of individuals? Many other context lacking as well. This is clearly written for the 96% statistic shock, not to inform anyone.
- nicoburns 4y ago
  > Also, “biomass” is a strange term. Is that literally an estimate of mass? It is indeed. The idea being that individuals vary greatly (it doesn't make sense to compare individual counts of humans with individual counts of ants for example), and that mass at least roughly accounts for the size of individuals.
  - club_tropical 4y ago
    But, especially in mammals, it is the individual animal that is the fundamental unit. A cheetah and an elephant are unique individuated specimens; it doesn’t make sense to compare their mass. In ants/bees it’s maybe something like “number of colonies/hives” that is the meaningful unit. Why would anyone compare across species by mass- that is a reductive number, you can’t infer anything meaningful out of it. Also, certainly not by percentage - have to look at absolute numbers of meaningful units over time.
    - pvaldes 4y ago
      > it is the individual animal that is the fundamental unit. Not. This is a very common mistake among people that does not understand ecology.
      - club_tropical 4y ago
        You can call me a heretic for questioning His Majesty The Ecologist, but the emperor wears no clothes and percentage of aggregate biomass is the most meaningless metric I've ever heard to study mammals.
        4y ago
astroalex 4y ago
Where are you seeing that this statistic is only about megafauna? I know the article talks a lot about megafauna extinction, but the specific statistic I posted does not mention this, at least that I can see. https://ourworldindata.org/mammals#wild-mammals-make-up-only-a-few-percent-of-the-world-s-mammals https://ourworldindata.org/mammals#wild-mammals-make-up-only... I think the title of this post should be edited if it is indeed misleading.

deathanatos 4y ago

Certainly the article might not be credible, but can you cite the relevant text from the article, so that the rest of us can quickly verify your claim? I'm not seeing where in the article this is stated.

pvaldes 4y ago
whales, dolphins and seals are also excluded. > "biomass from marine mammals – mainly whales – is not included" They discuss specifically about megafauna and large terrestrial mammals in most paragraphs and figures.
- astroalex 4y ago
  In the specific section that I took this statistic from, whales seem to be included: https://ourworldindata.org/mammals#wild-mammals-make-up-only-a-few-percent-of-the-world-s-mammals https://ourworldindata.org/mammals#wild-mammals-make-up-only...

nightpool 4y ago

Is this true? This source (https://www.pnas.org/doi/10.1073/pnas.1711842115 https://www.pnas.org/doi/10.1073/pnas.1711842115) gives a very similar percentage (95.8% of all wild mammals) and doesn't mention anything about excluding rodents or bats from the categorization of wild mammals. Is it in a footnote somewhere that I'm missing?

club_tropical 4y ago

Also, “biomass” is a strange term. Is that literally an estimate of mass? Or count of individuals? Many other context lacking as well. This is clearly written for the 96% statistic shock, not to inform anyone.

nicoburns 4y ago
> Also, “biomass” is a strange term. Is that literally an estimate of mass? It is indeed. The idea being that individuals vary greatly (it doesn't make sense to compare individual counts of humans with individual counts of ants for example), and that mass at least roughly accounts for the size of individuals.
- club_tropical 4y ago
  But, especially in mammals, it is the individual animal that is the fundamental unit. A cheetah and an elephant are unique individuated specimens; it doesn’t make sense to compare their mass. In ants/bees it’s maybe something like “number of colonies/hives” that is the meaningful unit. Why would anyone compare across species by mass- that is a reductive number, you can’t infer anything meaningful out of it. Also, certainly not by percentage - have to look at absolute numbers of meaningful units over time.
  - pvaldes 4y ago
    > it is the individual animal that is the fundamental unit. Not. This is a very common mistake among people that does not understand ecology.
    - club_tropical 4y ago
      You can call me a heretic for questioning His Majesty The Ecologist, but the emperor wears no clothes and percentage of aggregate biomass is the most meaningless metric I've ever heard to study mammals.
      - 4y ago

astroalex 4y ago

Where are you seeing that this statistic is only about megafauna? I know the article talks a lot about megafauna extinction, but the specific statistic I posted does not mention this, at least that I can see. https://ourworldindata.org/mammals#wild-mammals-make-up-only-a-few-percent-of-the-world-s-mammals https://ourworldindata.org/mammals#wild-mammals-make-up-only... I think the title of this post should be edited if it is indeed misleading.