73,000 years ago they were building up massive numbers of automobiles and power plants I guess.
You would know that if you had watched that wonderful educational documentary following the life of a stone age family. You can catch the reruns, it’s called “The Flintstones”.
Seventy-three thousand years ago was right after probably the biggest earth event in the last 100,000 years. That is the eruption of Mt. Toba, in Indonesia, which left a crater 18 by 65 miles in diameter. Probably caused nuclear winter, was followed by a major downturn in world temperatures, and may have diminished human population to no more than 5 to 10,000 individuals.