Washington DC: In a new analysis of early hominin body size evolution, researchers have suggested that the earliest Homogenus may not have been larger than their predecessors.
The George Washington University research has also challenged numerous adaptive hypotheses based around the idea that the origins of the Homo coincided with, or were driven by an increase in body mass.
In the research, researcher Mark Grabowski has provided the most comprehensive set of body mass estimates, species averages and species averages by sex for fossil hominins to date.
The analysis of the research shows that early hominins were generally smaller than previously thought and that the increase in body size occurred not between australopiths and the origins of Homo but later with H. erectus (the first species widely found outside of Africa).
Grabowski said that one of their major results is that they found no evidence that the earliest members of human genus differed in body mass from earlier australopiths (some of the earliest species of hominins).
Further author Bernard Wood said that this study shows that body size did not make a sharp uptick with the arrival of early Homo and his prediction is that this is just the first of many preconceptions about early Homo that will be debunked in the next few years.
In addition, authors also found that the level of size difference between males and females (sexual dimorphism) appears to have only slightly decreased from earlier hominin species by the time of early H. erectus, and only decreased to modern human-like low levels later in our lineage.