TLDR: Modern humans, the sole surviving hominins, interbred with Neanderthals and Denisovans, inheriting crucial adaptations and contributing to their extinction.
This article is a summary of a You Tube video “When We Met Other Human Species” by PBS Eons
Key Takeaways:
- Modern Human Uniqueness: We are currently the only surviving hominin species, a solitary branch on the hominin family tree.
- Ancient Coexistence: Eurasia, around 100,000 years ago, was inhabited by multiple hominin species, including Neanderthals and Denisovans.
- Neanderthals’ Extensive Presence: Neanderthals existed across Europe and Asia, from 450,000 to around 40,000 years ago. They were anatomically similar to modern humans and exhibited sophisticated behaviors.
- Interbreeding with Neanderthals: Modern humans interbred with Neanderthals, as evidenced by the Neanderthal DNA present in many current populations (up to 2% in Europeans and Asians).
- Genetic Impact of Neanderthals: Neanderthal genes have contributed to various human traits, particularly in immune responses and certain environmental adaptations, but also potentially harmful traits like increased blood clot risk.
- Discovery of Denisovans: Denisovans, a recently discovered hominin species, were identified primarily through genetic analysis and a few fossil remains, mostly from Denisova Cave in Siberia.
- Denisovan Genetic Contribution: Denisovan DNA is present in several modern human populations, particularly in East and South Asia, and Melanesians, contributing to adaptation to high altitude and other environmental factors.
- Multiple Interbreeding Events: Evidence suggests that Homo sapiens interbred with Neanderthals and Denisovans multiple times and in different locations.
- Extinction of Other Hominins: The disappearance of Neanderthals and possibly Denisovans is attributed to factors like climate change, competition, and diminishing populations, rather than direct conflict with modern humans.
- Hominin Genetic Legacy: The genetic contributions from other hominins have been crucial in human adaptation to different environments, indicating the importance of this inter-species interaction in our evolutionary history.
