Vini Jr. representative of Africans with Archaic Ancestral Admixture
H/t Wikipedia
by Shi Huang
The first goal for Brazil in this World Cup was scored by star forward Vini Jr., who displays certain features often regarded as relatively archaic in human morphology. Some traits considered ancestral or primitive (such as alveolar prognathism) are common in Africa but rare in Eurasia. This suggests that such traits are more readily preserved, or less likely to be replaced and eliminated, in African populations than in Eurasian ones.
From the ClevelandClinic.org:
Prognathism is when your upper jaw, lower jaw or both jaws protrude (jut out). It can look different ways, depending on the type:
- Mandibular prognathism (most common): Your lower jaw sticks out farther than your upper jaw. Another name for it is Habsburg jaw. This name comes from the Habsburg royal dynasty in Spain. Many family members from the 1500s through the 1700s had a pronounced lower jaw.
- Maxillary prognathism: Your upper jaw sticks out farther than it should. Maxillary prognathism is sometimes called alveolar prognathism.
- Bimaxillary prognathism: Both your upper and lower jaws protrude.
If modern humans first originated in Africa, as proposed by the Out-of-Africa model, then the earliest modern humans would presumably have carried these ancestral traits, which would have been retained in Africa to the present day. The Africans who migrated into Eurasia, however, would then have rapidly lost these traits.
Africans carry more ancestral alleles. This has been well demonstrated by the rooting of phylogenetic trees in Africa for both autosomes and uniparental DNAs by using the outgroup rooting method.
This raises an interesting question. If Eurasian populations have been more effective than African populations at eliminating ancestral traits and replacing them with derived ones, then why should the earliest modern humans be assumed to have originated in Africa rather than in Eurasia?
Human Diversity Explained by Maximum Genetic Distance
The MGD theory was inspired by an independent rediscovery of the GEP, first described in 1963. GEP originally led to the strict molecular clock (SMC)hypothesis, which in turn gave rise to the neutral theory. However, the SMC has since been disproven and replaced by the “relaxed clock,” which allows different species to have different mutation rates. This revision undermines the neutral theory—the only premise that supported the strict clock model. With the neutral theory effectively invalid, the MGD theory stands as the sole remaining explanation for genetic equidistance. A distance independent of rate can only reflect a saturation limit: the maximum genetic distance.
Explaining GEP is therefore a strict binary choice: either the SMC and neutral theory hold—excluding MGD—or they fail, leaving MGD as the only viable explanation. This establishes a clear “either–or” relationship. The competition between MGD and the Neutral Theory is an absolutely unambiguous binary choice—not only by logic but also by fact. For 60 years, molecular evolution has had only two competing explanations for the genetic equidistance phenomenon, and no others. This stands in sharp contrast to Darwin’s theory of natural selection, where countless rival theories exist—without exaggeration.
The MGD theory overturns many phylogenetic conclusions that relied on the now-discredited SMC and neutral theory. It redefines our understanding of evolutionary change by emphasizing the saturation limits of genetic diversity. Importantly, it also challenges prevailing models of human origins, providing strong support for the Out of East Asia hypothesis for the origin of modern humans or Homo sapiens.
Bio: Dr. Shi Huang (Twitter) has Ph.D. in biochemistry from the University of California-Davis in 1988. He did a post-doc at the University of California-San Diego in from 1989-1992 and was a member of the faculty of the Sanford-Burnham Shi Huang received his B.S. in genetics from Fudan University in Shanghai and his Ph.D. in biochemistry from the University of California-Davis in 1988.
During his early career at the Pew Institute, Dr. Huang [was] “studying the relationship between genetic diversity and epigenetic complexity and its role in common diseases and evolution… We proposed a novel hypothesis of genetic diversity and evolution, the Maximum Genetic Diversity (MGD) hypothesis… Genetic diversity of a species has an upper limit as set up by the epigenetic complexity levels…”
