Chapter 16, Problem 10STP

Summary Introduction

To explain:

The multiregional hypothesis and the “Out of Africa” hypothesis in the context of Human evolution.

Introduction:

Human evolution is a topic of so many debates and it is based on so many hypotheses. Evolution is referred to as a change in the characteristics of the organisms in a population over a period of time. These characteristics are hereditary and passed to the offspring. The key force which leads to evolution is Natural Selection. Both these hypotheses agree that human evolution began from the African continent as the very first humans were originated there but they contradict the course of evolution of Modern Man.

Explanation of Solution

A multiregional hypothesis states that all the primitive species of man such as Neanderthals, Denisovans and archaic sapiens belonged to the same species, i.e., they are the members representing the same species. It proposes that these are like just the regional variants of the same species just like the different ethnic groups present today. Geneflow played a major role and ensured that they don’t evolve into distinct species. Inbreeding in them ensured the process of gene flow among them. Several pieces of evidence support this hypothesis such as Gene flow, fossil evidence, Y chromosome, mitochondrial DNA, etc.

Whereas “Out of Africa” hypothesis states that the African man migrated out of Africa around 100,000 years ago to the different regions of Europe, Eurasia and these migrating African species replaced the archaic human species endemic to these regions. This proposes that the African population was the first one to expand on the earth, the population in other regions such as in Europe, Asia and other regions of the earth, developed lately. They develop due to parallel evolution occurred in these species.

Conclusion

Human evolution is a highly unresolved mystery due to a lack of evidence and missing fossil records. Still, some scientists describe the current scenario of human evolution as a result of multi-regional evolution while others describe it as a result of “Out of Africa” hypothesis, whereas some scientists consider it a blend of these two.