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. To explore this phenomenon, we develop a Malthusian growth model with hybridization in human evolution. Our hunting-gathering Malthusian economy features two initial 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. A higher hybridization rate reduces long-run population size but raises long-run output per capita for the surviving populations in this Malthusian economy. A sufficiently high hybridization rate may even cause the hybrid human population to dominate the population as 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, may have caused the extinction of archaic humans and non-hybrid early modern humans. Finally, we also use the Malthusian model to shed some light on the proportion of Neanderthal DNA 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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