For more than two decades, international teams of paleoanthropologists have been discovering human-like fossils from a medieval archaeological site in the former Soviet Republic of Georgia known as Dmanisi.
A new human Georgian skull fuels the dilemma further. In 1991, David Lordkipanidze of the Georgian National Museum in Tbilisi discovered the first four human-like fossils.
Increased archaeological interest in this Georgian site began in 1936 following the discovery of ancient and medieval artifacts.
The discovery of teeth from an extinct rhino in 1983, followed by the discovery of stone tools in 1984, led to an increased archaeological and paleontological interest in Dmanisi. Last week the discovery of a fifth Dmanisi skull reported in the journal Science fuels the escalating dilemma of the struggling human evolution industry.
New Findings
While the first four human-like skulls unearthed by Lordkipanidze were largely fragmented, the morphology of this fifth cranium with mandible “presents a new face for our genus Homo,” according to Ann Gibbons, Science commentator in the article entitled “A Complete Skull from Dmanisi, Georgia, and the Evolutionary Biology of Early Homo.” The new evidence presented undermines long-held theories on human evolution.
In a PBS NewsHour interview by chief correspondent Jeffrey Brown, Lordkipanidze explained that “this new discovery shows that many features which we previously thought as variability and diversity could be lumped in one group.” Brown noted that “fossils currently identified as different species may actually be variations within a single species.”
“The species we thought were different species in Africa now we realize probably are variants of the same species,” aired in the PBS report from an unnamed scientist. Brown quickly replied, “Other scientists were more cautious in making that leap, though, even as they acknowledged that the new findings, published in the journal ‘Science,’ were spectacular, indeed.” The title of the PBS segment was “1.8 million-year-old skull may revise understanding of human evolution.”
Not a New Species
In an NPR interview of Adam Van Arsdale, assistant professor of anthropology at Wellesley College in Massachusetts, hosted by news director John Dankosky, “It’s not a new species,” explained Arsdale. “It’s not from a new location. It’s the same old species we’ve had for a long time and at a site that we already have four relatively complete skulls.”
The evidence causing the chaos centers on the variation between the fossilized skulls. “Actually, what kind of shape differences exist between these specimens,” Arsdale explains, “similar [to the] kind of range of variation as you’d find under a human sample.”
Associated Press science writer, Seth Borenstein, reporting on PhysOrg, highlighted the center of the controversy: “For years, some scientists have said humans evolved from only one or two species, much like tree branches out from a trunk, while others say the process was more like a bush with several offshoots that went nowhere… 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.” The key phrase causing the dilemma is “variations in one species.”
Transitional Links
Humanoid fossil fragments, once thought to be possible evidence for human evolution by means of natural selection, are one species, not the “innumerable” transitional links as predicted by Charles Darwin in The Origin of Species (1859).
In the “Hominid Skull Spurs Radical Rewrite of Human Evolution” article published in Discover Magazine, Gemma Tarlach notes that “The view [Dmanisi] challenges long-held ideas about human evolution and could upend decades of classifying early hominids into different species, such as Homo erectus, Homo rudolfensis, and Homo habilis.”
“In addition,” Tarlach continued, “variations between the skull and those of other early hominids found at the site are no more significant than differences among modern humans, suggesting the fossils represent one species.”
Even the Guardian, a UK Huffington Post forerunner, chimed in with the news release: “skull of Homo erectus throws story of human evolution into disarray.” Ian Sample, Guardian science correspondent explains the industry’s dilemma:
“Experts believe the skull is one of the most important fossils finds to date, but it has proved as controversial as it is stunning. Analysis of the skull and other remains at Dmanisi suggests that scientists have been too ready to name separate species of human ancestors in Africa. Many of those species may now have to be wiped from the textbooks.”
“The significance is difficult to overstate. It is stunning in its completeness. This is going to be one of the real classics in paleoanthropology,” said Tim White, an expert on human evolution at the University of California, Berkeley, in an interview with Sample.
Shaky Ground
“Over decades excavating sites in Africa,” according to Sample, “researchers have named half a dozen different species of early human ancestor, but most, if not all, are now on shaky ground.”
“If the scientists are right,” Sample continues, “it would trim the base of the human evolutionary tree and spell the end for names such as H rudolfensis, H gautengensis, H ergaster, and possibly H habilis.”
“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.
Lordkipanidze’s findings are further fragmenting evolution scientists. “The specimen is wonderful and an important contribution to the hominin record in a temporal period where there are woefully too few fossils,” Lee Berger, a paleoanthropologist at the University of the Witwatersrand in Johannesburg, explained to CNN. The suggestion that these fossils prove an evolving lineage of Homo erectus in Asia and Africa, Berger said, is “taking the available evidence too far.”
Other scientists are even more adamant. “No way this extraordinarily important specimen is Homo erectus,” Ian Tattersall, curator emeritus at the American Museum of Natural History anthropology division, said in an email. The museum’s Hall of Human Origins contains examples of human evolutionary history, with distinct Homo species reflected in major fossil finds such as H ergaster and H erectus.
Lordkipanidze’s evidence even perpetuates evolution’s long-standing human evolution debate between Darwin’s out-of-Africa and Ernst Haeckel’s out-of-Asia theory. The evidence further accentuates rather than resolves the gargantuan missing-link gaps between Australopithecines and Homo erectus and between Homo erectus and Homo sapiens – us.
Extending Darwin’s dilemma, Ernst Mayr, in the book What Makes Biology Unique? (2004) notes –
“The earliest fossils of Homo, Homo rudolfensis, and Homo erectus are separated from Australopithecus by a large, unbridged gap.”
Curiously enough, Lordkipanidze’s article never addresses how a 1.8 million-year-old fossil could be unearthed from the 9th century A.D. medieval village. The evidence argues against the validity of current dating methods commonly employed as “scientific evidence” in the evolution industry.
The Georgian skull further fuels the human evolution dilemma.
Genesis
The convergence of scientific dating evidence is compatible with the Genesis account written by Moses.
Nicolas Stenonius, a pioneer in the fields of anatomy and geology, overturned the popular idea of the time that fossils grew in the ground. Stenonius has since been recognized as one of the founders of modern stratigraphy and modern geology. In the words of Stenonius during the Scientific Revolution –
In regard to the time of the universal deluge, secular history is not at variance with sacred history.”
Click to study evolutionary perspectives on the Fossil Record further.
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Links
- Glossary defines terms associated with explaining the theory of biological evolution.
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- Studying Evolution delves into the terms species and natural selection and how they have changed since The Origin of Species was published in 1859.
- What is Science investigates Charles Darwin’s approach to science and how the principles of modern science are used for different investigative purposes.
- The Evolution and Science category features articles studying how the intersection of evolution and science influences the current understanding of evolution.
- The Theory and Consensus category features articles examining how scientific findings are influencing the scientific consensus on the essential tenets of evolution, including Natural Selection.
