Researchers from the universities of Oxford and Edinburgh have very recently calculated that humanity’s roots stretch back to about 3.3 million years ago. This is 500,000 years earlier than had previously been thought. They believe that our ancestors weighed about six stones and slept in trees. Scientists had thought that the earliest record of the genus Homo was dated to 2.8 million years ago.
It is still unclear as to which species of the Homo genus emerged but they believe that it is most likely to be Homo habilis. It is believed that this species diverged from the Australopithecus group of species. In Morocco, about 3 million years later, at about 300,000 years ago, Homo sapiens emerged.
The new research was led by Hans Püschel, a mammalian palaeontologist at Edinburgh and his brother Thomas a palaeoanthropologist at Oxford. Their research would not have taken place without the Covid-19 pandemic.
The scientists were forced to abandon field trips to Kenya and Mozambique so they turned to their computers. It appears that they developed an algorithm to bring together a wide variety of data on genetics, archaeology and the anatomy of early Homo sapiens.
Previously our knowledge of human’s early development came from fossil and archaeological records. They took a different approach using computer modelling which enabled them to create precise evolutionary trees.
They worked out when the genetic codes diverged using genetic information from humans, gorillas and chimpanzees together with sequences from species such as Neanderthals. They added information regarding anatomy to trace the paths of evolution and they used carbon-dating of fossils to calibrate their data according to The Times science editor, Ben Spencer.
They worked out that the Homo genus first diverged from earlier species (non-human I guess) between 4.3 million and 2.56 million years ago. They decided upon a midpoint of 3.3 million years ago as a reasonable estimate.
They believe that these earliest humans would have been much smaller than ourselves. They say that their body mass was roughly 38 kg. They stood on two legs and probably slept in trees for protection from predators.
They also believe that they were mostly vegetarian and sometimes scavenged for meat with the help of stone tools. They used tools to crack bones to get to the bone marrow. And they used tools to get at seeds.
The tools allowed them to exploit the environment better and obtain a higher number of calories. This resulted in the growth of their brains and therefore their intelligence. When Homo erectus emerged about 1.5 million years later they were taller and more intelligent, more organised and operated in teams and hunted in packs.
Postscript: this is, strictly speaking, about the human-animal relationship because it is about the moment when non-human animals evolved into human animals. That is the connection in my opinion.
SOME ARTICLES ON HUMAN BEHAVIOR IN RELATION TO ANIMALS: