Part 4/13:
Language and Social Structures: sophisticated tool use and fire control fostered social cooperation and communication, foundational elements for culture and civilization. As tool use became more advanced, it unlocked further capabilities—clothing, shelter, boats—allowing humans to colonize diverse climates and territories.
Industrial Revolution: the advent of steamships, airplanes, and mechanized agriculture further accelerated change, reshaping our environment and increasing gene flow across populations. This interconnectedness introduces even greater genetic mixing, creating hybrid vigor (heterosis), which boosts species resilience but also complicates evolutionary trajectories.