Article- A Single-Couple Human Origin is Possible


The paper "A Single-Couple Human Origin is Possible" by Ola Hössjer and Ann Gauger (2019) presents a mathematical model that suggests that a single couple could have given rise to the entire human population. The model assumes that the population was homogeneous (no geographic subdivision), dioecious and diploid (males and females are distinguished, and each individual has two copies of a non-sex chromosome), and reproduction is selectively neutral.

The model also assumes that the mutation rate is constant over time, and that there is no natural selection. Under these assumptions, the model shows that a single-couple origin of humanity is possible as recent as 100,000 years ago.

The paper's findings have been met with some skepticism from the scientific community. Some critics have argued that the model's assumptions are too unrealistic, and that it is unlikely that a single couple could have survived and reproduced to the point where they gave rise to the entire human population.

Other critics have pointed out that the paper does not take into account the possibility of gene flow from other populations. This could have introduced genetic diversity into the human population, making it more difficult to trace back to a single couple.

Despite these criticisms, the paper's findings have generated some interesting discussion about the possibility of a single-couple human origin. The paper's authors argue that their findings should not be taken as definitive proof that a single couple gave rise to humanity, but that they do provide some evidence that it is at least possible.

The paper's findings could have implications for our understanding of human evolution. If it is indeed possible that a single couple gave rise to humanity, then this would suggest that the human population has a much more recent and common origin than previously thought. This could have important implications for our understanding of human diversity, as well as our relationship to other hominin species.

Overall, the paper "A Single-Couple Human Origin is Possible" provides an interesting and thought-provoking contribution to the debate about the origins of humanity. The paper's findings should not be taken as definitive proof of a single-couple origin, but they do provide some evidence that it is at least possible. The paper's findings could have important implications for our understanding of human evolution, and they deserve to be further investigated.

Article Snippets

The problem of inferring history from genetic data is complex and underdetermined; there are many possible scenarios that would explain the same data. It can be made more tractable by making reasonable simplifications to the model, but it is continually important to remember what has been demonstrated and what is merely a parsimonious working assumption. In this paper we have chosen to model the demographic ancestry of humanity using the simplest of assumptions, with a homogeneous population whose size can vary over time. All other assumptions such as the mutation rates were standard, and no natural selection was in operation. Using a previously published backwards simulation method and some newly developed and faster algorithms, we run our single-couple origin model of humanity and compare the results to allele frequency spectra and linkage disequilibrium statistics from current genetic data. We show that a single-couple origin of humanity as recent as 500kya is consistent with data. With only minor modifications of our parsimonious model assumptions, we suggest that a single-couple origin 100kya, or more recently, is possible.

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