I try not to respond to cases of "police brutality" during protests. It's simply too irritating of an issue to discuss, and there's rarely room for a stasis issue to discuss in the first place.
No, the reason I love this country is that even when protesters gather up and complain about class structure, they just make their own.
Humans don't operate without leaders and castes. It just doesn't happen. I don't want to say these folks wasted their time, but, it certainly wasn't well-spent.
Egalitarian social organization dominates about 99% of human history.
I would positively love to see the mathematical and historical legwork to support that.
Read what I linked, read some of the references. There you go. The mathematical side is actually pretty simple: humans have been around for ~200,000 years and for almost that entire time have lived life as hunter-gatherers. There is strong evidence that hunter-gatherer, especially immediate return, groups were highly egalitarian (again, see linked article as I cba to dig up more right now). It is only in the past ~10,000 years, once we started to shift more towards fixed agriculture and (semi)-permanent settlements that things like the ability to store food and develop systems of trade and private property that we moved towards more stratified social structures. So that puts it at about 5% of human history.
Seems like I never remembered to bookmark much of my references for this stuff sadly. Guns, Germs, and Steel is a good book on the subject.
First off, I feel I should put a disclaimer on the Jared Diamond recommendation. Without going into specific details of specific instances such as his blatantly offensive mischaracterization of various Polynesian cultures, the guy talks out of his ass. He has an agenda that consists largely of assuaging guilty white consciences over the results of Western European colonialism, and he publishes a lot of pseudo-scientific drivel in pop-science journals to support that agenda.
Senn, social stratification is something that doesn't occur in hunter-gatherer societies. It is very limited in horticultural societies as well. We don't see evidence of significant social stratification in the archaeological or ethnographic record until the advent of intensive agriculture. Caste systems are a very extreme example of social stratification, which is only really present in a very small minority of known human cultures.
For specific examples of how hunter-gatherer societies work in relatively contemporary times, there is a wealth of ethnography out there. The !Kung people of the Kalahari desert are a classic textbook example of h/g egalitarianism, and they have been studied by a number of great anthropologists. For some really readable classic ethnography, you might look at Bronislaw Malinowski's work in Melanesia. Just try to keep in mind that Malinowski worked in the earlier part of the twentieth century, and he was a structural functionalist who supported colonialism. Still, his ethnography is great and very accessible to non-academics.
If you must turn to the dark side of pop-science, look for Steven Mithen's "After the Ice." It provides a great, accessible review of human prehistory as we know it through the archaeological record. Unlike Jared Diamond, Mithen is an actual anthropologist with a great deal of credibility in the field of lithic archaeology.