Hacker News Reader

I'd say that 4-13 billion tons is a lot.

Quick grab from the Wikipedia page re biomass.

humans: ~0.1 billion tonnes

domesticated animals: ~0.7 billion tonnes

earthworms: ~1 billion tonnes

annual cereal crops: ~2.3 billion tonnes

Antarctic krill: ~0.5 billion tonnes

fish: 0.8-2.0 billion tonnes

According to https://www.quora.com/How-many-cells-does-a-blue-whale-have There are about 10^16 cells in a blue whale.

So maybe about 10^13 blue whales? Seems unlikely.

One cell type (prokaryote, tiny) is not like the other (eukaryote, huge)

Serious question: is "blue whales" a common informal unit for biomass?

I think 'large animal that people are familiar with' is for science popularizing articles. Let's say it was less than a 10,000 blue whales, they might have wanted to calculate it in African Elephants.

is cell count / microorganism density relatively constant through species?

How different would 'a blue whale worth of lab mice' be if counting volume/mass/cells/microorganisms?