LETTER TO THE BOOKSHELF
A letter regarding Greg Laden's review of The Fossil Chronicles
Flores Skeletons: Irrational Scientists or Imaginary Species?
Greg Laden reviewed The Fossil Chronicles in the January–February, 2012, American Scientist. On July 4, 2012, we submitted a 4,100 word response. Subsequently the Editor, David Schoonmaker, allotted 500 words online. Our full critique appears at http://liangbuacave.org.
After studying the Liang Bua Cave skeletons in 2005, we were denied further access to what Laden calls “one of the most important finds of the past hundred years.” These bones do not represent a new species, but are important because they spotlight paleoanthropology’s idiosyncrasies.
The Fossil Chronicles recount Dean Falk’s long-running disagreement with Ralph Holloway about the interpretation of fossil hominin endocasts, plus her speculations about the endocast of LB1, the only known skull from Liang Bua Cave. Laden adds further gratuitous disparagement of Ralph Holloway, unacceptably unprofessional in American Scientist.
Laden parrots Falk’s conclusions about these remains: “Homo floresiensis is normal, although very different than expected, just as Taung was different than expected.” But evidence for evolution over two centuries comprises greater than 200 fossil hominin skulls, not two. Some finds were celebrated as ancestors for decades, then rejected later. Piltdown’s fraudulent skull presented the reverse of Taung’s pattern, blocking acceptance of the Dart’s insight for three decades. Ramapithecus beguiled most professionals and students nearly as long, illustrating a “bandwagon effect” in human ancestry reconstruction, among professionals and journalists.
For truth Laden substitutes consensus: “The history of the study of human evolution shows that surprising findings make well-educated and otherwise rational people behave irrationally for a time, until everyone eventually settles on a new view.” Such statements explain the bandwagon effect. Questioning majority view is “irrational,” imposing a penalty with that label, while joining the majority carries easier access to funding and publication, as for “Homo floresiensis” advocates.
Many supposedly “unique” features of LB1 (short stature, low humeral torsion) are shared with other extant humans; others (mandibles lacking external chins, rotated premolar teeth) are common in Flores Rampasasa among extant Australomelanesians, while LB1’s tiny brain, marked asymmetry, and unusually short femora signal developmental abnormality. Our hypothesis, offered in 2006, remains constant: LB1 is an abnormal individual from a relatively recent Flores population. Contradictorially, supporters of “H. floresiensis” originally held that it evolved from H. erectus isolated on Flores over more than 800,000 years, then switched in 2007 to attribute its small brain and short stature to African ancestors a million years before reaching Flores.
The idea that the Liang Bua Cave skeletons represent a new species has—unlike Taung but strikingly like Piltdown and Ramapithecus—decidedly not been a minority viewpoint championed bravely by a few dissidents against widespread opposition. From the first the new diminutive species was a popular, widely romanticised interpretation. Its few critics are held, as by Laden here, to be irrational. This situation will change, but only when there is more general realization that “wrapping events into a good story that supports one’s case” per Sloman’s review in the same American Scientist issue, is alien to the best traditions of science, however appealing to bandwagoneers.
Robert B. Eckhardt, Ph.D.
Professor of Developmental Genetics and Evolutionary Morphology
Department of Kinesiology
University Park, PA 16802 USA
Maciej Henneberg, Ph.D., D.Sc., FAIBiol
Wood Jones Professor of Anthropological and Comparative Anatomy
University of Adelaide
Adelaide, SA 5005
"Penguins are 10 times older than humans and have been here for a very, very long time," said Daniel Ksepka, Ph.D., a North Carolina State University research assistant professor. Dr. Ksepka researches the evolution of penguins and how they came to inhabit the African continent.
Because penguins have been around for over 60 million years, their fossil record is extensive. Fossils that Dr. Ksepka and his colleagues have discovered provide clues about migration patterns and the diversity of penguin species.
to view all of our Pizza Lunch Podcasts!
A free daily summary of the latest news in scientific research. Each story is summarized concisely and linked directly to the original source for further reading.
An early peek at each new issue, with descriptions of feature articles, columns,
and more. Every other issue contains links to everything in the latest issue's table of contents.
News of book reviews published in
and around the web, as well as other noteworthy happenings in the world of science books.
To sign up for automatic emails of the
Update and Scientists' Nightstand issues, create an
online profile, then sign up in the
My AmSci area.