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. In a Malthusian growth model with initial non-hybrid human populations, we derive population dynamics and the conditions for a hybrid human population to emerge and survive in the long run, 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 for the surviving populations. A sufficiently high hybridization rate even causes the hybrid human population to be the only surviving human species. 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 humans and early modern humans. Finally, we also shed some light on the proportion of Neanderthal ancestry in the modern human population.

• 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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