Body Size Increase Not A Major Factor for Evolution in Homo Genus

According to a new analysis, body size may not have been the contributing factor that gave rise to the Homo genus, a theory that is quite contrary to many current evolutionary studies hypotheses that indicate a body size increase provided the boost that led to the origin of humans.

Body Size Does Not Matter In Evolutionary Sciences Suggests Study

Evolutionary studies may soon be rocked by a new study published by Mark Grabowski, assistant research professor at George Washington University’s Center for the Advanced Study of Human Paleobiology (CASHP).

Grabowski’s research in essence explains that early hominins of the Homo genus may not have been much larger than other early hominins from other species. His analysis is revolutionary in the field of evolution as almost all theories regarding the origins of Homo rely on the purported body size increase at specific times in the evolutionary chain.
Early Hominin Skull Comparisons

The Myth of Body Size and the Origin of the Homo Genus

The study analysis has used the latest methodologies and also the largest fossil samples of early hominins to create the most comprehensive data set on body mass estimations, focusing on species averages in general as well as by sex for each hominin.

The data revealed that the body size increase didn’t occur between Australopithecus and the earliest hominins of Homo, but rather showed up in the fossils much later in Homo erectus.

As a Fulbright scholar at the University of Oslo’s Centre for Ecological and Evolutionary Synthesis, Grabowski believes the most important findings in the study are knowing that increase in body size was not the the factor that set us (modern humans and our Homo genus) apart from our earlier hominin ancestors.

Because body mass did not set us apart from them, many other assumptions about the jump from the past hominins to our genus will be seen as myths now,  too. These unconfirmed theories that might be included in the myth debunking is that earlier hominins were small in stature because of dietary restrictions.

The last major publication on hominin body mass was published in 1992 by Henry M. McHenry and in the two decades that have since passed, many fossils have been found that would add to the data set, presenting more conclusive details about early species of humans.

The study researchers drew on McHenry’s results, applying new methodologies of analyzing the fossil data set, and updating the fossil hominin body estimates. This recent study is the largest, most comprehensive fossil data set for early hominins and may be used as the new standard for anthropologists.

Body Size Increase Not A Major Factor for Evolution in Homo Genus

Body Size Sexual Dimorphism and The Evolutionary Link

Grabowski’s study didn’t end with updating the fossil collection data set, but instead also revealed that dimorphism decreased very slightly in comparing the early hominins to H. erectus. Only much, much later in our human evolution did the researchers see the modern levels of dimorphism that we currently have.

Though this may seem insignificant after such a major feat in compiling the comprehensive data, the findings could in fact challenge the monogamous social structure of relationships that evolutionary assumptions have attributed to earlier Homo members.

While body size may not have led to the origin of our species, it may lead to some interesting new research in the field of evolutionary studies thanks to Grabowski’s updated fossil data set.


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