A Malthusian model of hybridization in human evolution

Chu, Angus C. (2024): A Malthusian model of hybridization in human evolution.

Abstract

Early modern humans interbred with archaic humans. We explore this phenomenon through an economic lens to reveal what shaped the origins of our species. In a Malthusian growth model with initial non-hybrid humans, we derive population dynamics and the conditions for hybrid humans to emerge and survive, which explains why modern humans still carry DNA from archaic humans. It is possible for a higher hybridization rate to reduce long-run population size and raise long-run output per capita. A sufficiently high hybridization rate causes only hybrid humans to survive. This result captures the probable scenario that all modern humans are hybrid descendants of archaic and early modern humans and provides the following novel insight: modern humans, which emerged from interbreeding, caused the extinction of archaic and early modern humans. Finally, our analysis also shows that the low proportion of Neanderthal-derived DNA in modern humans is due to their relatively early extinction.

• Item Type: MPRA Paper
• Language: English
• Keywords: Ancient human interbreeding; natural selection; Malthusian growth theory
• Subjects: N - Economic History > N1 - Macroeconomics and Monetary Economics ; Industrial Structure ; Growth ; Fluctuations > N10 - General, International, or Comparative; O - Economic Development, Innovation, Technological Change, and Growth > O1 - Economic Development > O13 - Agriculture ; Natural Resources ; Energy ; Environment ; Other Primary Products; Q - Agricultural and Natural Resource Economics ; Environmental and Ecological Economics > Q5 - Environmental Economics > Q56 - Environment and Development ; Environment and Trade ; Sustainability ; Environmental Accounts and Accounting ; Environmental Equity ; Population Growth

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