Comment by cbkeller | Hacker News Reader

Comment by cbkeller | Hacker News Reader

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Geologist here! The report in question [1] and supplement [2] seem pretty think-tank-y, but I would say they pass the sniff test to first order (if we have a biologist or ecologist around, they could probably say better). The focus on animals makes it relatively plausible -- these are charismatic and easy to observe, but a lot of the ecological heavy lifting / biogeochemical nutrient cycling is really carried out by microbes, which are are probably doing better. Microbes also represent most of Earth's genetic diversity, and will pretty certainly survive any mass extinction we throw at them.

In any case, the Guardian article is correct in claiming that

>Many scientists believe the world has begun a sixth mass extinction

This is pretty well accepted among geologists and paleontologists, as far as I've seen. Here's one relatively recent perspective on the issue, which covers some of the back-and-forth: http://science.sciencemag.org/content/360/6393/1080.2

[1] https://s3.amazonaws.com/wwfassets/downloads/lpr2018_full_re... [2] http://awsassets.panda.org/downloads/lpr2018_technical_suppl...

> a lot of the ecological heavy lifting / biogeochemical nutrient cycling is really carried out by microbes

What really worries me is what is going to happen when all those millions of tons of microplastics become nanoplastics and are spread far enough to become part of the foodchain, even down at the microbial level. The dark end of that space is pretty terrifying for life on Earth, IMHO.

Interesting point. It looks like there may be negative consequences for eukaryotic algae / phytoplankton [e.g., 1], but on the plus side some prokaryotes are able to usefully metabolize plastics and "bioremediate" the problem a bit [e.g., 2]

[1] https://www.sciencedirect.com/science/article/pii/S0166445X1... [2] https://link.springer.com/article/10.1007/s00253-018-9195-y

Thanks for at least trying to answer the question, just to be clear, I'm 100% convinced in climate change and some kind of extinction happening, just querying the '60% of all animals' headline.

It also looks like the claim here is something like "the total animal population has decreased by 60% on average over all studied localities since 1970" rather than the more dire "60% of all animal species have gone extinct since 1970" so we're not anywhere near the 90% species extinction of the Permo-Triassic yet!

>> Many scientists believe the world has begun a sixth mass extinction.

>This is pretty well accepted among geologists and paleontologists

Do they believe humanity will be one of the survivors?

Sigh.

a) This is not in their field of expertise. b) If there is any species that has the best chance of survival, it's humanity.

Oh now you're just tempting fate. Surely that distinction goes to the cockroaches?

I haven't seen much of a consensus on that one yet!

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