The oldest recognizable signs of permanent human habitation and urbanization go back abut 12,500 years -- sites like Jericho<span> and </span>Göbekli Tepe<span> both show persistent communities who had the resources to build permanent structures and enough surplus food and labor to support specialists -- however both of those sites also show that hunting remained an important component of the community's way of life. There are certainly other examples of permanent settlements from this same period scattered around, particularly in the region of modern Syria, Turkey, Armenia and Iraq. </span>
People need to believe they have equal social and political rights, else there would be mass protests, revolutions and anarchy. Whether they actually exist in real life is irrelevant here, only the belief matters.
The primary difference in the social structures of humans and animals is the forced imposition of order in human society, leading to a more 'collective' society, instead of the usual 'survival of the fittest/law of the jungle' structure.
And the concept of equal rights is necessary to achieve this imposition of order.
In my opinion, a human society following 'law of the jungle' would be unsustainable, simply because humans as a species are too weak to survive as individuals. The greatest strength of our species is our mental faculty. This leads to the sum of the parts being greater than the whole. As individuals though, we would fail to harness this strength.
Therefore, equal rights do offer us an evolutionary advantage, since they allow us to cluster together, and grow as a population, which is the only way for us to survive.
You should look up Progressivism. Progressivists dealt with a lot of reforms in the early 1900s.
Alternatively, try looking up “US health bills since 1900.” If you need a starting point, look up the Pure Food and Drug Act/Meat Inspection Act (both in 1906) and Upton Sinclair’s “The Jungle,” which had a particularly large impact on meat inspection.
