Evidence for Human Evolution Still Scant and Controversial After 25 Years
A post made 2 weeks ago highlighted how in 1981, Constance Holden wrote in Science that emotions, rather than abundant evidence, often rule the field of paleoanthropology and its claims about human evolution. Yesterday, an article by Charles Matthews in the San Jose Mercury News reiterates that same point. Reviewing a book by Ann Gibbons, Matthews notes:
"Gibbons, who reports on human evolution for Science magazine, gives a lucid account of the science involved in finding fossils, establishing how old they are, and ascertaining whether they in fact belong to the ancestors of humankind. She also shows how difficult and sometimes dangerous the work of hunting for 7 million-year-old fossils can be. And that, like most humans, anthropologists are subject to such emotions as ambition and jealousy, especially when they're Indiana Jonesing for the next big find." (Discovering fossils can be difficult and dangerous by Charles Matthews)
The book is said to document the many unfortunate hardships experienced by paleoanthropologists while in the field. While the commitment of paleoanthropologists to their research is admirable, one can only wonder how these hardships would strengthen one's psychological commitment to one's favored view of human evolution. This is especially poignant when one considers that their hypotheses are based upon little evidence:
"We're not talking about complete skeletons but about teeth, the occasional jawbone or skull or thighbone, sometimes on the verge of crumbling into chalky dust.
'Together, the fossils collected in the 1990s and early 2000s would cover a large desk and would represent a few dozen individuals at least,'' she notes. But too many pieces are still missing from the puzzle -- including fossils of the ancestors of our closest relatives, chimpanzees and gorillas -- to allow for a clear picture of the evolutionary lineage." (Discovering fossils can be difficult and dangerous by Charles Matthews)
This gives pause to ask whether statements we often hear affirming some hypothesis about human evolution are based upon clear evidence. Yet compare Gibbons' findings to what Constance Holden wrote in 1981:
"The field of paleoanthropology naturally excites interest because of our own interest in origins. And, because conclusions of emotional significance to many must be drawn from extremely paltry evidence, it is often difficult to separate the personal from the scientific disputes raging in the field.
The primary scientific evidence is a pitifully small array of bones from which to construct man's evolutionary history. One anthropologist has compared the task to that of reconstructing the plot of War and Peace with 13 randomly selected pages. Conflicts tend to last longer because it is so difficult to find conclusive evidence to send a theory packing." (Constance Holden, "The Politics of Paleoanthropology," Science, p.737 (August 14, 1981).)
Perhaps very little has changed in the past 25 years.