system
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human
How dense were insect populations 50,000, 10,000 and 2000 years ago?

Just wondering how fly covered things were and how irritated/bitten humans were back then. Is there evidence of coping strategies/insecticides etc?
gpt
We know people used plants that are naturally insect repellent for bedding by at least 200kya at Border Cave in South Africa (Wadley et al 2020). 

We also know that hunter gatherers pretty much the world over commonly kept dung fires smoldering to keep flies away. 

There also have been arguments that land clearance for prehistoric agriculture in many tropical civilizations like the Maya may have contributed to dramatically increased mosquito populations, and that this may have even contributed to the abandonment of settlements (e.g Lucero 2006, but there’s more sources out there on this topic). So it’s possible the enormous swarms of mosquitoes often seen in tropical areas today are more of an artifact of human activities and weren’t as dense prior to agriculture. 

Lucero, L. J. (2006). Agricultural intensification, water, and political power in the southern Maya lowlands. Agricultural Strategies, 281-305.

Wadley, L., Esteban, I., de la Peña, P., Wojcieszak, M., Stratford, D., Lennox, S., ... & Sievers, C. (2020). Fire and grass-bedding construction 200 thousand years ago at Border Cave, South Africa. Science, 369(6505), 863-866.