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Tuesday, 22 September 2015

Bible in the News completely gets the Homo naledi story wrong. (Yet another reason why YECs cannot be trusted on science)

It has not taken long for the extreme YEC section of our community to respond to the magnificent Homo naledi fossil discover, as one can see in the latest Bible in the News podcast [1] where one can see the usual YEC techniques of uncritical appeal to YEC charlatans who lack any expertise in palaeoanthropology, reliance on secondary sources rather than read the freely available primary literature, and missing the central point by focusing on side issues.

On this point alone, the team behind BitN lose all credibility as they fail to provide a cogent, reasoned answer to the central fact: the richest ever discovery (> 1500 fossils) of fossils in Africa provide unambiguous evidence for the existence of a small-brained hominin species with a mix of primitive and modern features, whose remains were deliberately placed underground. Hand-waving the evidence away will not make this disappear, and all this does is confirm that the mililtant YEC wing of our community privileges human dogma over the unambiguous witness of the natural world. If YECs wonder why Christianity is increasingly being held in contempt by a younger generation, then they should look at their intellectually dishonest approach to science, and how it both alienates potential converts (and scientifically literate younger members) and brands our community as fundamentalist extremists.

I've pointed out repeatedly how special creationists have an appalling record of misrepresenting evolutionary biologists via such practices as quote mining. Unfortunately, the BitN podcast, after commenting on the National Geographic report of the Homo naledi discovery immediately poisoned the discussion by quote mining a 21 year old article in Time magazine:
The only certainty in this data-poor, imagination-rich, endlessly fascinating field is that there are plenty of surprises left to come.
Always suspect special creationists of quote mining, and check the source of the quote, as well as who else as quoted it. In this case, both the fact that Answers in Genesis and the Institute for Creation Research appeal to this quote, as well as other fundamentalist science denialists, raising both the likelihood of it being a quote mine (YECs have a thoroughly deserved reputation for taking quotes out of context) as well as BitN finding this quote not from the original magazine, but a YEC article raise red flags about the credibility of this podcast.

As for the Time article - written not by a palaeoanthropologist but a science journalist, and appearing not in the scientific literature but a news magazine - when one examines the it in detail, we find that the YECs have shamelessly taken it out of context. Evolution refers to fact (common descent), theory (the modern synthetic theory of evolution) and historical path (times and details of speciation). Disagreements about the latter two do not mean that the first aspect is in doubt, and it is intellectually dishonest for YECs to use ongoing argument about the latter point to claim that the fact of human evolution is in doubt. It is not, and when one reads the Time article, it is clear that the author is in no doubt about the fact of human evolution, but is reporting on the controversy about how human evolution took place:
The latest shocker comes in the current issue of Nature, where Chinese scientists have contended that the skull of a modern-looking human, found in their country a decade ago, is at least 200,000 years old - more than twice as old as any Homo sapiens specimen ever found in that part of the world. Moreover, the skull has features resembling those of contemporary Asians. The controversial implication: modern humans may not have evolved just in Africa, as most scientists believe, but may have emerged simultaneously in several regions of the globe.

The
Nature article came only a week after an even more surprising report in the competing journal Science. U.S. and Indonesian researchers said they had re-dated fossil skull fragments found at two sites on the island of Java. Instead of being a million years old, as earlier analysis suggested, the fossils appear to date back nearly 2 million years. They are from the species known as Homo erectus - the first primate to look anything like modern humans and the first to use fire and create sophisticated stone tools. Says F. Clark Howell, an anthropologist at the University of California, Berkeley: "This is just overwhelming. No one expected such an age."

If the evidence from Java holds up, it means that protohumans left their African homeland hundreds of thousands of years earlier than anyone had believed, long before the invention of the advanced stone tools that, according to current textbooks, made the exodus possible. It would also mean that
Homo erectus had plenty of time to evolve into two different species, one African and one Asian. Most researchers are convinced that the African branch of the family evolved into modern humans. But what about the Asian branch? Did it die out? Or did it also give rise to Homo sapiens, as the new Chinese evidence suggests? [2]
Far from falsifying the fact of human evolution, this was one part in the debate between supporters of the Out Of Africa hypothesis, versus the Multiregional hypothesis. To spin it as evidence that the field of palaeoanthropology is in crisis is fundamentally dishonest. Had the people behind the BitN podcast actually read and understood the Time article, they would have been aware of that fact, and would not have quoted it out of context. If, however, they have merely quoted a YEC article that included that quote, then they are guilty of shoddy research in failing to verify their references. Either option discredits BitN.

The article is 21 years old which is an eternity in science. In that time, there have been considerable discoveries made, all of which further confirm the fact that over time, the fossil record shows large-scale evolutionary change in the hominin record, with an increase in cranial size and tendency towards obligate bipedality. The inference that the fossil record is marginal is flatly refuted when you actually do some research. The palaeoanthropologists Matt Cartmill and Fred Smith noted in 2009 that:
Opponents of scientific biology are fond of dismissing that record as a pathetic handful of controversial fragments. If that were so, this book would be a lot shorter. An often-repeated creationist canard insists that all known human fossils would fit on a billiard table. This was probably true in the 19th century, but it has not been true for a hundred years. Known human fossils number in the thousands and represent the remains of hundreds of individuals...Having seen most of the major collections of human fossils in the world's museums, we can assure our readers that those collections can no longer be laid out on a billiard table. It would be hard to cram them into a boxcar. [3]
Having shown that BitN have resorted to opening with a YEC quote mine, demonstrating in the process their lack of research skills and complete ignorance of the field they are criticising,  BitN resort to a crude game of bait and switch when attacking the Homo naledi evidence. They begin by attacking the claim that the presence of the bones in such an inaccessble location is evidence for deliberate disposal:
Well if we are looking for examples of imagination rich thinking the discovery sure has a dose.  The Palaeontologists had a mystery on their hands because the bones were in a remote cave deep down so they had to come up with an explanation.
BitN quote the National Geographic article in which Berger and his team persuasively argue against alternative explanations for the presence of the bones deep in the cave such as occupation, accidental trapping in a disaster, predation, or deposition via water. Having done that, they are obliged to provide a substantive response to that argument, which requires them to quote the freely-available journal articles in which Berger and his team published their discovery. Instead, not only do they fail to reference the Berger articles, they quote a newspaper article, and not so subtly change the focus from how the fossils managed to get into such an inaccessible cave to the completely separate question of whether the bones represent a new species, or whether they indeed come from a single species. The question of whether the bones represent a new species or are indeed a single species does not change the fact that these bones represent hominins with a small cranial capacity, whose post-cranial data shows a mix of primitive and modern anatomy. This is yet more intellectually dishonest behaviour from the BitN team.


Furthermore, as the respected palaeoanthropologist John Hawks, part of the Berger team notes, the criticisms made by White that the Homo naledi bones actually belong to the existing species Homo erectus are demonstrably false:
Of course, Homo erectus is a very well-known species, and we compared the Dinaledi fossils to every specimen available to us. Many of our team have studied the originals of most Homo erectus remains around the world, and I have personally examined the key cranial and postcranial specimens from Dmanisi. So we examined this question in great detail as we studied the Homo naledi material.
How are we to know that Homo naledi is not the same as a primitive, small Homo erectus? Well, for one thing, at least two H. naledi individuals have endocranial volumes around 460 cc, much smaller than any H. erectus cranium ever found. There is barely any overlap between the larger individuals and H. erectus, with only a single H. erectus specimen coming close to the H. naledi range of variation in volume.

White doesn’t specify how many features would be sufficient in his view to define a species. It should be obvious that if we list 80 cranial and dental traits that are informative among all hominins, that most species will differ in only a relatively small fraction of those. Nevertheless our open access paper lists many clear differences between
H. naledi and H. erectus, including aspects of premolar crown and root morphology, the crown morphology of the molars (simplified in H. naledi, invariably crenulated and complex in H. erectus), vault shape (H. naledi does not have the elongated, low cranium of H. erectus) and mandibular shape—all listed on page 10 of our open access paper. Even setting aside the postcranial skeleton and the very small endocranial volume, these show H. naledi to be distinct from H. erectus.

When we look at the postcranial skeleton, there is simply no way that
H. naledi could be confused for H. erectus. H. naledi has a long, anteroposteriorally flattened and anteverted femur neck, which looks very different from African and Dmanisi femora attributed to H. erectus. The H. naledi tibia is exceptionally mediolaterally thin and long, with a rounded anterior border and tubercle for the pes anserinus tendon, all traits that we could not find in known tibiae attributed to H. erectus including Dmanisi. The H. naledi scapula has a superiorly oriented glenoid, very different from the Dmanisi scapula specimen or the Nariokotome H. erectus skeleton. The vertebrae of H. naledi do not match in proportions or morphology the comparable examples from Nariokotome or Dmanisi, and the pelvis of H. naledi exhibits a short, flared ilium unlike those known for H. erectus, including the Gona pelvic specimen.

It’s just a poor match to
H. erectus, so that the only way to make the H. naledi fossils fit within Homo erectus is to stretch that species beyond any other ever defined in the human lineage. [4] (Emphasis mine)
While White has a well-deserved reputation in the field, he comes from an older generation of palaeoanthropologists who as Hawks notes, have a tendency to issue statements from on high and expect to be taken on faith:
Some senior paleoanthropologists have unfortunately been accustomed to secretive practices. They may think that people will trust their authoritative pronouncements about fossil remains because no one will ever see the data. That’s an unscientific approach, and it leads to bad practices.

What we’re seeing now from senior scientists like Tim White and Jeffrey Schwartz is an unfortunate pattern. These scientists are used to being able to immediately talk to their cronies in the press with a knee-jerk reaction to new fossil publications, secure in the knowledge that the authors won’t release the data to contradict them. Even White, who has famously written (White 2000) that no one should publish on a fossil without seeing the original, has twice this year chased attention for his own fringe views about new species. [5]
Given that the Berger team have made the three dimensional fossil data fully available, so that anyone can download them, and either view them on a computer, or print them out and examine them, BitN, if they want to be taken seriously would be well advised to take Hawks advice, "...print out the fossils and take a careful look side-by-side [look]" and share their scientific conclusions with the scientific community. Until they do this, their claims can be dismissed out of hand.

Predictably, the team behind the BitN podcast appeal to the charlatans at the extreme YEC organisation Answers in Genesis in order to explain away the evidence. The author, Elizabeth Mitchell is not a palaeoanthropologist but an obstetrician by training. Furthermore, the article has not been peer reviewed by palaeoanthropologists, which means BitN are trusting an article written by someone who not only is not a palaeoanthropologist and not a scientist, but a member of an extreme science denialist organisation who reject almost all of modern science, and which has not been reviewed by experts in the field.

Furthermore, the YEC community is divided on the signifricance of the Homo naledi find, with AiG blithely declaring that it is an animal, while Kurt Wise, a prominent YEC  is quoted as saying:
“I think the case is very strong that these fossils are not just of the genus Homo, but are actually fully human (meaning they are descendants of Adam and Eve),” said Kurt Wise, director of the Center for Creation Research at Truett-McConnell College.
Fully human? Fully ape? When the YECs can’t even agree among themselves on how to classify the same find, not only does it show that they cannot be trusted to provide an authoritative, informed comment on these discoveries, it implicitly testifies to the status of these fossils as transitional fossils, given that the YEC denies a priori the concept of transitional fossils, and is forced to shoehorn them into either a ‘human’ or an ‘ape’ category.

The author of the BitN podcast appeals to Mitchell - a non-expert - because "as far as I am concerned Dr. Elizabeth Mitchell has it right." Those are strong words, particularly given that Mitchell's claim that the Homo naledi fossils are not human. Other YECs claim that they are. That obliges the BitN podcast author to inform us the specific, scientific reasons why he regards Mitchell's claims to be authoritative, and inform us of his scientific background in comparative anatomy which allows him to make this bold claim. If he cannot show us that he has the scientific background which permits him to make such a comment, and  provide the evidence to back up his claim that Mitchell's views not only trump that of the genuine experts in palaeoanthropology, then he should retract them immediately.

Conclusion

The BitN podcast continues an embarrassing trend in our community of militant fundamentalist YEC science denialists making outrageous claims about evolutionary biology with little to support their claims other than appeal to YEC charlatans, poorly-understood secondary sources, and quote mining. In so doing, the team show they know nothing about palaeoanthropology, as can be seen by their reliance on arguments that have been comprehensively dismantled by John Hawks, who unlike the BitN team actually have worked on the fossils and understand the subject.

One would trust that BitN would devote their next podcast to an unqualified retraction of their claims, and an apology to their audience for misleading them. Until they do this, they simply cannot be trusted on this subject.

References

1. http://www.bibleinthenews.com/Podcasts/484

2. Lemonick M.D. "How Man Began" Time March 14, 1994.

3. Cartmill M, Smith FH, Brown KB The Human Lineage xi (Wiley, 2009)

4. Hawks J "Is Homo naledi just a primitive version of Homo erectus?" John Hawks Weblog September 19 2015

5. ibid