5 ms·
This is called Petrichor and the human nose is indeed hyper sensitive to it (5 parts per trillion). https://en.m.wikipedia.org/wiki/Petrichor https://en.m.wiki
by konz 7y ago
This is called Petrichor and the human nose is indeed hyper sensitive to it (5 parts per trillion).
https://en.m.wikipedia.org/wiki/Petrichor https://en.m.wikipedia.org/wiki/Petrichor
- tomxor 7y agoSimilarly and linked in the same article, the human nose is sensitive to ozone in as little as 0.1 ppm, and it seems an unlikely coincidence that it starts to become hazardous to respiratory tissue above this concentration.
- duskwuff 7y agoThat seems like a stretch to me. Sources of hazardous concentrations of ozone are generally technogenic in nature -- the concentrations produced by lightning in the troposphere are far too low to pose any real danger. As such, there's no reason that humans (or any organisms) would have evolved to specifically detect that.
- tomxor 7y agoProbably not directly, but the mechanisms we evolve are generalized to some degree, i.e they often end up being useful for things our ancestors never encountered. Perhaps the method by which we smell give us a similar sense for some similarly hazardous molecules. According to the wiki O3 smells much like Chlorine, they are both highly oxidizing which is why they can be hazardous.
- bduerst 7y agoProbably more correlated to the survival aspect of being able to smell a thunderstorm and take shelter.
- MaxBarraclough 7y agoBut that's nowhere near 5 parts per trillion (0.000005 ppm).
- deleted 7y ago[deleted]