I’m super skeptical of this.
You don’t get oxygen toxicity, even breathing pure oxygen, unless you’re under significantly more pressure than atmospheric pressure…
So either this graphic is wrong/misleading, or the atmosphere was more than double current pressure for most of earth’s history… Which I’m pretty skeptical of.
Tar_alcaran@sh.itjust.works 2 months ago
That blue bar is extremely pessimistic. Humans can survive pretty well with 15% oxygen, and do so in several places in the Andes mountains, China and India.
Humans also don’t really have a problem with 30% oxygen, although that will definitely bring down the life expectancy.
On the other hand, note how those pointers talk about giant insects, megafauna and other scary things. Those are a much bigger problem than the air you’re breathing.
Eheran@lemmy.world 2 months ago
To add to this: At 3’500 meters above sea level, the pressure is down to 2/3 atmospheres. So instead of 21 kPa of oxygen partial pressure, it is only 14 kPa. So like breathing 14 % oxygen at sea level. People live at that height.
qjkxbmwvz@startrek.website 2 months ago
Dumb question, but in a very oxygen rich environment, can you just breathe through a paper bag or something? Mostly just breathe your own exhaled CO2 with a bit of O2 leaking in?
phdepressed@sh.itjust.works 2 months ago
For short periods maybe. You only use a few percent of the O2 you breathe in each time. But you also increase the CO2 each time. It’d depend on the amount of leak because you need enough O2 coming in but enough CO2 going out.
msage@programming.dev 2 months ago
So like how big mosquitos are we talking about?
About crabhead ticks?
Tar_alcaran@sh.itjust.works 2 months ago
Mosquitos are kind of modern, but think 40cm long, meter wide “dragonflies”, half-meter long “scorpions”, 60cm spiders with knifelike front legs and 250cm long millipedes (technically not an insect, but eh)
msage@programming.dev 2 months ago
Dragonflys don’t scare me, but if we got same proportional upgrades to anything that regularly bites, I would move underground.
refalo@programming.dev 2 months ago
why?
Droechai@lemm.ee 2 months ago
Oxygen is really rough on the DNA due to making the cells “rust” which hampers cell division and/or increases risks of mutations or cancers
grubberfly@mander.xyz 2 months ago
So those memes that were “warning” that oxygen was dangerous because it created rust in metal rods is actually true ??