EA - What’s alive right now? by rosehadshar

Link to original articleWelcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: What’s alive right now?, published by rosehadshar on August 10, 2022 on The Effective Altruism Forum. In this post, I lay out some different ways of looking at what’s alive right now. This seems worth knowing about to me, but also hard to grasp because of how huge the numbers are. A lot of what I’m doing in the post is trying to find ways to get my human brain to understand big numbers about how the world is. I don’t have a considered view on which organisms are sentient or how much, or on how much different organisms matter morally compared to other organisms. Biomass I like this graphic a lot: It’s from Our World in Data article on Biodiversity and Wildlife [I recommend following the link so you can zoom in on the graphic], which pulls from a 2018 paper by Bar-On, Phillips and Milo. Some of the headlines that OWID pull out: Life on earth is dominated by plants – they make up 82% of global biomass. The animal kingdom makes up just 0.4% of global biomass. Humans account for just 0.01% of biomass. However, our livestock outweighs wild mammals and birds ten-fold. The reason to look at life on earth in terms of biomass rather than individual organisms is an intuition that this makes it more comparable: otherwise the numbers get dominated by loads and loads of tiny things, and the bigger things (which most people care more about) barely show up. Numbers I’m still kind of interested in the absolute numbers though. I think this is partly because my brain is better at conceptualising ‘individual organisms’ than ‘weight in tonnes of carbon’. Bar-On, Phillips and Milo do give estimates for the absolute numbers (which they call ‘abundance’), to the nearest order of magnitude: TaxonBillion tonnes of carbonAbundancePlantsTrees 45010^13BacteriaTerrestrial deep subsurface60 10^30Marine deep subsurface7 10^29Soil7 10^29Marine1.3 10^29Total 7010^30Fungi 1210^27ArchaeaTerrestrial deep subsurface4 10^29Marine deep subsurface3 10^29Soil0.5 10^28Marine0.3 10^28Total 710^29Protists 410^27AnimalsChordatesFish0.7 10^15Livestock0.1 10^10Humans0.06 10^10Wild mammals0.007 -Wild birds0.002 10^11ArthropodsTerrestrial0.2 10^18Marine1 10^20Annelids0.2 10^18Molluscs0.2 10^18Cnidarians0.1 10^16Nematodes0.02 10^21Total 210^21Viruses 0.210^31 (See also this post by Brian Tomasik for another set of estimates and much number crunching.) I want to zoom in on the animals part of this table. First, for people who like me don’t intuit how big the difference between 10^10 and 10^18 is, here is the animals part of the same table with zeros: ChordatesFishLivestockHumansWild mammals-Wild birdsArthropodsTerrestrialMarineAnnelidsMolluscsCnidariansNematodes 1,000,000,000,000,000 10,000,000,000 10,000,000,000 100,000,000,000 100,000,000,000,000,000 10,000,000,000,000,000,000 100,000,000,000,000,000 100,000,000,000,000,000 10,000,000,000,000,000 100,000,000,000,000,000,000 So for every one human, there’s something like 10 billion nematodes. The estimates Bar-On, Phillips and Milo give are orders of magnitude (which makes sense given how big most of the numbers are). For some of the smaller numbers, we can get more precise estimates. Here’s a table I made with some more numbers I was interested and able to find: Order of magnitude from Bar-On, Phillips and Milo EstimateYearFish1 quadrillion (a million billions)Farmed fish126.5 billion2015Wild fish999,873.5 billion (999.9 trillion)-Livestock10 billionPoultry25.7 billion2018Cows1.5 billion2018Sheep1.2 billion2014Goats1 billion2014Pigs1 billion2018Humans10 billion-8 billion2022Wild mammals--550 billion- My brain can track these numbers better than the raw orders of magnitude. But even smaller numbers would be even easier for me to make sense of. One way of getting smaller numbers is to think about how many organisms of different types there are for every individual hum...