The news is all over the place, and we don’t know what to make of it. Let’s start with this writeup at PhysOrg: 1.8M-year-old skull gives glimpse of our evolution, suggests early man was single species. They say, with our bold font:
The discovery of a 1.8-million-year-old skull of a human ancestor buried under a medieval Georgian village provides a vivid picture of early evolution and indicates our family tree may have fewer branches than some believe, scientists say.
The fossil is the most complete pre-human skull uncovered. With other partial remains previously found at the rural site, it gives researchers the earliest evidence of human ancestors moving out of Africa and spreading north to the rest of the world, according to a study published Thursday in the journal Science.
Here’s the published paper, but you’ll need a subscription to see more than the abstract: A Complete Skull from Dmanisi, Georgia, and the Evolutionary Biology of Early Homo. That same issue of Science also has this: Stunning Skull Gives a Fresh Portrait of Early Humans.
Why does one newly-found skull suggest fewer ancestral branches? Let’s continue with PhysOrg:
When examined with the earlier Georgian finds, the skull “shows that this special immigration out of Africa happened much earlier than we thought and a much more primitive group did it,” said study lead author David Lordkipanidze, director of the Georgia National Museum. “This is important to understanding human evolution.”
Okay, but what about the family tree? Let’s read on:
For years, some scientists have said humans evolved from only one or two species, much like a tree branches out from a trunk, while others say the process was more like a bush with several offshoots that went nowhere.
Even bush-favoring scientists say these findings show one single species nearly 2 million years ago at the former Soviet republic site. But they disagree that the same conclusion can be said for bones found elsewhere, such as Africa. However, Lordkipanidze and colleagues point out that the skulls found in Georgia are different sizes but considered to be are the same species. So, they reason, it’s likely the various skulls found in different places and times in Africa may not be different species, but variations in one species.
How does one species have different sized skulls? PhysOrg tells us:
To see how a species can vary, just look in the mirror, they said. “Danny DeVito, Michael Jordan and Shaquille O’Neal are the same species,” Lordkipanidze said.
Well, okay, but what species was the skull they found? PhysOrg continues:
The adult male skull found wasn’t from our species, Homo sapiens. It was from an ancestral species—in the same genus or class called Homo—that led to modern humans. Scientists say the Dmanisi population is likely an early part of our long-lived primary ancestral species, Homo erectus.
But not everyone agrees. Here’s more:
Fred Spoor at the Max Planck Institute in Germany, a competitor and proponent of a busy family tree with many species disagreed with the study’s overall conclusion, but he lauded the Georgia skull discovery as critical and even beautiful.
Spoor said it seems to have captured a crucial point in the evolutionary process where our ancestors transitioned from Homo habilis to Homo erectus — although the study authors said that depiction is going a bit too far.
This article in the Guardian, Skull of Homo erectus throws story of human evolution into disarray, says, with our bold font:
The latest skull discovered in Dmanisi belonged to an adult male and was the largest of the haul. It had a long face and big, chunky teeth. But at just under 550 cubic centimetres, it also had the smallest braincase of all the individuals found at the site. The dimensions were so strange that one scientist at the site joked that they should leave it in the ground.
The odd dimensions of the fossil prompted the team to look at normal skull variation, both in modern humans and chimps, to see how they compared. They found that while the Dmanisi skulls looked different to one another, the variations were no greater than those seen among modern people and among chimps.
The scientists went on to compare the Dmanisi remains with those of supposedly different species of human ancestor that lived in Africa at the time. They concluded that the variation among them was no greater than that seen at Dmanisi. Rather than being separate species, the human ancestors found in Africa from the same period may simply be normal variants of H erectus.
One more excerpt and then you’re on your own:
“I think they will be proved right that some of those early African fossils can reasonably join a variable Homo erectus species,” said Chris Stringer, head of human origins at the Natural History Museum in London. “But Africa is a huge continent with a deep record of the earliest stages of human evolution, and there certainly seems to have been species-level diversity there prior to two million years ago. So I still doubt that all of the ‘early Homo’ fossils can reasonably be lumped into an evolving Homo erectus lineage. We need similarly complete African fossils from two to 2.5m years ago to test that idea properly.”
Your Curmudgeon has no opinion. The issue seems unsettled. But we do know one thing — the creationists will be going wild over this. You know the lines they’ll take: (1) the Darwinists don’t know what they’re doing; (2) the Darwinists keep changing their theories; (3) their so-called science books are all wrong; and (4) the Darwinists still refuse to consider Genesis. Oh, and the ever-popular: “I ain’t no kin to no monkey!” It should be fun to watch their reactions.
See also: Casey Reacts to the New Skull Discovery.
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