Jim Foley Archives

D4500-oblique.jpg

A new paper was recently published, and widely reported in the media, about a hominid skull discovered at the Dmanisi site in Georgia in 2005 (Lordkipanidze et al, 2013, Gibbons 2013). The fossil, D4500, is believed to belong to the same individual as a lower jaw fossil, D2600, previously found at the site. The combined skull, designated by the authors as “Skull 5” (the 5th skull from Dmanisi) is almost completely and perfectly preserved, making it one of the most spectacular finds in the entire hominid fossil record. And Dmanisi is rapidly becoming one of the most important sites ever found in the study of human evolution.

Skull 5’s brain volume of 546 cm3 is very small. The other Dmanisi skulls are between 600 cm3 and 730 cm3. (Earlier papers gave the size of the largest one as 780 cm3, but that estimate appears to have been reduced. By comparison, the average modern human brain size is 1350 cm3.) However the fossil also has a large and robust jaw bone, and a large and projecting face. This combination of a very small brain and a large face differs from all other known Homo fossils. The fossil is of a mature adult, and because of the robustness of the skull it is thought to belong to a male.

Scientists are naturally delighted at the discovery of such a superb fossil, but the real impact of Skull 5 comes from the conclusions that the authors have drawn from it.

The Dmanisi fossils are different enough from each other that had they been found at different locations, they might have been classified into different species. Similar differences have been used to create species such as Homo habilis and Homo rudolfensis in the past. The authors believe that the Dmanisi fossils all belong to one species, both because they all come from the same time and place, and because the pattern and amount of variability found between the skulls is similar to that found in populations of modern humans, chimpanzees, and bonobos.

Following that line of reasoning, they conclude that since a similar pattern of variation exists for all early Homo fossils in Africa, and in the absence of any evidence that the supposed different species of Homo were adapted to different ecological niches, the default and most parsimonious assumption should be that all of these fossils belong to a single highly variable lineage (though they recognize that this claim remains to be tested, and alternative scenarios exist). This would mean that Homo habilis, Homo rudolfensis, Homo ergaster and some other more obscure names did not really exist as separate species. The name of that single species would, for reasons of priority, be Homo erectus. Specimens allocated to H. ergaster would then be called Homo erectus ergaster, as a time-limited subspecies. The Dmanisi scientists had previously named a new species, Homo georgicus, for the Dmanisi fossils, but now retract that name and suggest that because the Dmanisi fossils arose from an ergaster population, they should be called Homo erectus ergaster georgicus.

Denisovans and the species problem

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A few weeks ago I blogged on the Denisovans, a new group of human relatives discovered through genetic analysis of two bones from Denisova in Siberia (Reich et al. 2010, Nature 468:1053). Fascinatingly, the Denisovans seem to have made about a 5% contribution to the genome of living Melanesians.

I mentioned that this new discovery did not seem compatible with a young-earth creationist framework, and awaited with interest a creationist explanation of the findings. Answers In Genesis (AIG) has now commented on the Denisovans. No explanation, merely a one-sentence handwaving solution:

Answers in Genesis Wrote:

But the most interesting twist (from the evolutionary perspective) is that modern humans from New Guinea have Denisovan DNA. While an evolutionary perspective interprets this as meaning that Guineans’ ancestors “interbred” with Denisovans, a biblical perspective interprets this as simply meaning that the descendants of one of the people groups leaving Babel eventually settled in what is now New Guinea.

It’s not clear what this even means. After all, their ‘biblical perspective’ had exactly the same interpretation (that the descendants of a group leaving Babel settled in New Guinea) even before we knew about the Denisovan genetic contribution. This ‘explanation’ fails to address a key point: how did the Denisovan genes get into Melanesians, if not by interbreeding with Denisovans?

And the above scenario doesn’t resolve any of the other problems with a young-earth framework.

A Full Genome from Denisova, Siberia

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Last week a paper was published on the DNA sequencing of the complete genome of an approximately 40,000 year old finger bone from Denisova in Southern Siberia (Reich et al. 2010). There are a number of very significant findings in the paper.

1) The results showed that the Denisova individual was more closely related to Neanderthals than to modern humans. However, the Denisovan does not fall within the range of Neanderthal variation. There are a few lines of evidence suggesting that the Denisovan and Neanderthal lineages had separate histories once they diverged and did not form a single population. The Neanderthal genomes sequenced so far have low genetic diversity, indicating that Neanderthals passed through a genetic bottleneck after splitting from the Denisovans. With only one Denisovan genome available as yet, we don’t know how diverse they were.

Denisova1.png

2) Even more spectacular was the finding that the Denisovan genome appears to have made a genetic contribution of about 4.8% (+/- 0.5%) to the genomes of living Melanesians. Interestingly, they did not contribute to the genomes of modern populations such as Han Chinese and Mongolians which live near Denisova now. The Denisovans obviously interbred with the ancestors of modern Melanesians at some point, but it seems unlikely to have happened at Denisova, which suggests that the Denisovans lived over a considerable area of eastern Asia.

This finding recalls another major discovery made earlier this year, which was that Neanderthals appear to have contributed from 1% to 4% of the genome of all living non-Africans (Green et al. 2010; Panda’s Thumb blogged about it in June). This was not expected, given that earlier mitochondrial DNA (mtDNA) results showed no evidence of any genetic mixing between Neanderthals and modern humans (but did not exclude the possibility either). The new Reich et al paper has improved the precision of this estimate; they calculate that Neanderthals contributed 2.5% (+/- 0.6%) to the genome of modern non-Africans. That means that the Neanderthals and Denisovans together account for an impressive 7.5% of the ancestry of modern Melanesians.

A widely publicised paper published on May 7th 2010 announced that a first draft of the Neandertal genome from three individuals - 4 billion base pairs - had been sequenced (Green et al. 2010: A draft sequence of the Neanderthal genome). This was about two thirds of the entire Neanderthal genome. Even more sensationally, their findings seem to show convincingly that Neanderthals interbred with humans and that non-African modern humans contain between 1% and 4% of Neanderthal genes. Because Asians as well as Europeans have these Neanderthal genes, the researchers believe the most likely explanation is that the interbreeding occurred in the Middle East when modern humans first left Africa between 60,000 and 80,000 years ago, and before they expanded into the rest of the world.

A couple of weeks earlier, on April 20th, Nature had published an online article about results presented at a scientific conference by a group from New Mexico, but not yet released in the scientific literature (Dalton 2010: Neanderthals may have interbred with humans). Unlike the Green et al. paper, these researchers did not sequence Neanderthal genes directly and compare them with those of modern humans. Instead, they tried to explain the patterns of variation in gene sequences found in modern humans, and found that the patterns seemed to show humans had interbred with an archaic species at two different periods: around 60,000 years ago in the Middle East, and about 45,000 years ago in eastern Asia. The first of these periods would match up well with the time and place at which Green et al. claim human/Neanderthal interbreeding occurred. The second period might be showing that some humans bred with a late population of H. erectus or H. heidelbergensis in Asia.

The recent discovery of the “X woman” in southern Siberia might also be relevant here (Krause et al. 2010). This fossil, about 30,000-50,000 years old, was an insignificant-looking finger bone whose mitochondrial DNA was not only very different from any modern human, but even more different from humans than Neandertals are. Although we don’t know what its owner looked like or even what species it belonged to, it is striking evidence that some very genetically unusual people were living in Asia at about the same timeframe that the New Mexico group believes some archaic genes found their way into the human population.

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Two spectacular new hominid fossils found in a cave at Malapa in South Africa in 2008 and 2009 have been assigned to a new species, Australopithecus sediba (‘sediba’ means ‘wellspring’ in the local seSotho language). Discovered by a team led by Lee Berger and Paul Dirks, it is claimed by them to be the best candidate yet for an immediate ancestor to the genus Homo. The fossils are between 1.78 and 1.95 million years old, about the same date of the oldest Homo erectus fossils.

The first fossil, MH1, found by Lee Berger’s son Matthew, is an almost complete skull and partial skeleton of an 11 to 12 year old boy. The 2nd fossil, MH2, is a partial skeleton of an adult female, including some jaw fragments. The boy’s brain has a typical australopithecine size of 420cc, compared to the smallest Homo brain of 510cc. Both skeletons are small, about 130cm (4’3”) tall.

Au. sediba is most similar to, and quite likely descended from, Au. africanus. The upper limbs are long, and similar to other australopithecines. Many features of the hip, knee and ankle bones show it was bipedal, like other australopithecines, but the foot bones are still quite primitive. However Berger et al. list many other features of the skull, teeth, and pelvis in which it resembles early Homo fossils.

The discoverers have suggested that Au. sediba might be ancestral to either Homo habilis or Homo rudolfensis, or that it might be a closely related sister group to Homo - not a direct ancestor, but a close cousin. As the authors admit, these two individuals existed after the earliest known Homo fossils (at about 2.3 million years), so they can’t be human ancestors. However, it’s possible that the sediba species had already existed for a few hundred thousand years and that early members of it could have been human ancestors.

New findings about the Hobbit

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Since the “Hobbit” fossil LB1 was discovered on the Indonesian island of Flores in 2004, debate has raged as to whether it is a new species of hominid (Homo floresiensis), or a pathological modern human specimen. And, if it is a new species, where it should fit in the human family tree - a near-human relative, a dwarf Homo erectus, or something else?

The November issue of the Journal of Human Evolution was devoted to Homo floresiensis, with a number of papers on various aspects of its anatomy and environment.

Argue et al. have performed the first cladistic study of LB1. Cladistics uses comparisons of characteristics of specimens to try and determine their evolutionary relationships. Their results showed that LB1 most likely split from the rest of the genus Homo either after H. rudolfensis but before H. habilis, or after H. habilis. It therefore apparently evolved from an early Homo species, sometime between about 1.5 and 1.9 million years ago. They also tested whether LB1 could have shared a unique common ancestor with either Homo erectus or Homo sapiens, but both of these hypotheses were strongly rejected. Their full conclusion was:

Argue et al. 2009 Wrote:

Based on rigorous cladistic analyses, we propose that H. floresiensis evolved in the Late Pliocene or Early Pleistocene. The first of our two equally parsimonious trees suggests that H. floresiensis branched after H. rudolfensis (represented by KNM-ER 1470) but prior to the divergence of H. habilis (represented by KNM-ER 1813 and OH 24). Alternatively, our results are equally supportive of H. floresiensis branching after the emergence of H. habilis. Our results sustain H. floresiensis as a new species (Brown et al., 2004; Morwood et al., 2005) and favor the hypothesis that H. floresiensis descended from an early species of Homo (Falk et al., 2005; Argue et al., 2006; Larson et al., 2007; Tocheri et al., 2007). We find no evidence of close phylogenetic relations to H. sapiens, and reject the idea that the Liang Bua remains represent a pathological modern human. Importantly, we also are unable to link H. floresiensis phylogenetically to H. erectus, rejecting the hypothesis that the small enigmatic bones resulted from insular dwarfing of H. erectus. It is surely time we accepted the reality of H. floresiensis as a species and seek answers to the questions that this species poses, not least of which is: who were its ancestors?”

Other papers reach similar conclusions:

Telling apes from humans

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Creationists are always very definite that there are absolutely, absolutely no transitional fossils between apes and humans. For example, according to a 1990 article by Answers In Genesis (AIG)

When complete fossils are found, they are easy to assign clearly as either ‘ape’ or human, there are only ‘ape-men’ where imagination colored by belief in evolution is applied to fragmented bits and pieces.

Very well then. Here are some photos of fossil skulls, all to the same scale. Some are of humans, some of apes. Care to identify which are which?

Fossil 1 Fossil 2
Fossil 3

Answers after the fold.

Dmanisi in the news

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The English media is full of articles about the Dmanisi fossils, based on a talk by David Lordkipanidze at the British Science Festival. The articles mention the discovery of five or six specimens, with some giving the impression that these are new discoveries. The New Scientist commented that “it’s not clear whether Lordkipanidze was presenting new data, or simply wrapping up the story so far for a more lay audience at the festival.” However some of the other newspapers such as the Guardian clarified that most of these fossils were discovered early this decade, along with another recent discovery that is not yet published. According to The Times, this recent find is “a fifth well-preserved skull, the most complete yet”, which will make it a spectacular fossil. This is probably the specimen shown a photo in many of the articles, still half-embedded in rock.

As is usual, a number of newspapers somewhat overstated the significance of the find, especially the Daily Mail with its headline “Ancient skeletons discovered in Georgia threaten to overturn the theory of human evolution”. This is highly misleading. The Dmanisi fossils are a tremendous discovery, and may well change our ideas about some details of where, when, and how we evolved, but they’re certainly not going to overturn the idea of human evolution. They are actually superb evidence for human evolution.

The Dmanisi hominids are from the country of Georgia (http://www.talkorigins.org/faqs/homs/d2700.html). A number of skulls have been found so far, ranging from about 850 cc (the lower end of the H. erectus range) down to 600 cc (well into the H. habilis range). In 2007, details of some skeletal material was published.

The brain sizes of these skulls straddle the gap that creationists like to claim exists between humans and australopithecines. The skulls are also intermediate anatomically, looking like primitive H. erectus skulls with some habilis features. The same is true of the skeletal material: the creatures were indisputably bipedal, but have a number of primitive features.

Naturally, creationists don’t have a clue what these fossils are. Some of them think they’re humans, some think they’re apes, and, as I blogged last year, they’re both wrong:

Dmanisi fossils - more transitional than ever
Dmanisi and Answers in Genesis

Note: In the initial version of this post, I thought the articles were referring to new fossil discoveries, which turned out to be (mostly) not the case, so the post has been corrected accordingly.

Creationists, whether YECs or IDers, just can’t help falling over themselves in their eagerness to tar the theory of evolution (and Darwin) as racist. This is nonsense for any number of historical reasons. Racism obviously had existed long before Darwin. Darwin, though he sometimes expressed statements that are racist by modern standards, was remarkably non-racist by the standards of his age and treated people of other races without prejudice, as well as being passionately opposed to slavery (he was far less racist than most Christians and creationists of the time). It’s true that evolution was pressed into service to provide justification for racism, but the same could be said of Christianity. Such arguments were invalid and are not a logical consequence of evolution. Nor is there any truth to the smears that evolution caused the Holocaust.

But the strangest thing about creationists trying to link evolution and racism is that creationists generally accept some of the theory of evolution. Not all of it obviously, but the major creationist organizations all accept the idea of natural selection and evolution within ‘kinds’ (a non-scientific creationist term that, in practice, is defined to be whatever amount of evolution creationists are willing to accept). Answers in Genesis even enthusiastically affirms that it has no problem with the concept of natural selection.

Creationists don’t accept that evolutionary change can accumulate indefinitely and that humans could have evolved from apes or earlier primitive animals, but that’s not the scale of change involved in the evolution of all living humans from their most recent common ancestors. Human racial differences are minor and easily explained by natural selection. To creationists, humans are a ‘kind’, and human races evolved within that kind. So if the theory of evolution is racist, that makes creationism equally racist.

Footprints through time

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A recent paper (Bennett et al. 2009) announced the discovery of 1.5 million year old fossilized footprints from Ileret, Kenya, almost certainly belonging to Homo erectus (see also this commentary article by Ann Gibbons). Homo erectus was already known from fossils such as the Turkana Boy to be very similar to modern humans below the neck, and completely adapted to bipedal locomotion. So it was no suprise when the footprint analysis showed that the owners of the Ileret footprints had a fully modern foot shape and were pushing off their big toes and shifting their weight exactly as modern humans do.

Answers in Genesis, of course, was delighted to report on this, claiming that it confirmed their belief that Homo erectus was a modern human (never mind the more primitive features of pelvis, shoulder and skull found in Homo erectus). So did the Institute for Creation Research. But AIG and ICR carefully avoided mentioning information from the paper that did not fit with their agenda.

In 1997 the first successful extraction of Neandertal DNA was announced to great fanfare (Krings et al. 1997). This DNA was not from the nuclear DNA (from cell nuclei) which determines most of our physical characteristics, but mitochondrial DNA (mtDNA) from the small energy-producing organelles which are inside all of our cells 1. It so happens that mtDNA is easier to extract from ancient bones than is nuclear DNA. Krings et al reconstructed a 379 base sequence from the Neandertal mtDNA, out of the full mtDNA length of more than 16,000 bases. Since then, many other researchers have also extracted mtDNA sequences from Neandertal bones (and one team has even recovered some nuclear DNA).

Now, for the first time, a complete mtDNA sequence has been recovered, from a 38,000 year old Neandertal fossil from the Vindija cave in Croatia. The results were published in August 2008 in the journal Cell: A Complete Neandertal Mitochondrial Genome Sequence Determined by High-Throughput Sequencing (Green et al. 2008).

Here is one of the most important conclusions from the paper’s summary:

Green et al. 2008 Wrote:

Analysis of the assembled sequence unequivocally establishes that the Neandertal mtDNA falls outside the variation of extant human mtDNAs, and allows an estimate of the divergence date between the two mtDNA lineages of 660,000 ± 140,000 years.

The Neandertal mtDNA sequence was compared with mtDNA from chimpanzees and 53 modern humans. The human mtDNA sequences had between 2 and 118 differences from each other. The number of differences between the human mtDNAs and the Neandertal mtDNA varied from 201 to 234. This graph shows the differences between the human, Neandertal and chimp groups, and the human group:

Dmanisi and Answers in Genesis

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Recently, I blogged about the newly discovered skeletal bones of the Dmanisi hominids (Lordkipanidze et al. 2007, Gibbons 2007, Lieberman 2007), and the Discovery Institute’s response to them. (In a nutshell, Casey Luskin of the DI attempted to argue that the Dmanisi hominids were apes, an argument that is untenable for any number of reasons).

I know of only one other creationist discussion of the Dmanisi skeletons, in an article by Answers in Genesis (AIG) (scroll down to the 2nd item). It is fascinating to observe that AIG has decided that the Dmanisi hominids are humans, in contrast to Luskin’s opinion that they were probably apes. If either side is right, the other must be hopelessly incompetent (not excluding, of course, the possibility that both are incompetent).

It’s worth noting that AIG also disagrees with their own “expert” on human evolution, Marvin Lubenow. Lubenow is the author of Bones of Contention (2nd edition, 2004), the leading creationist book on human evolution. It is enthusiastically praised by creationists, and sold and recommended by AIG, who call it “the leading creationist work in fossil study today”. Lubenow’s book doesn’t have any discussion of the Dmanisi skulls (the skeletal bones were not then known), but he does put the largest of the 3 Dmanisi skulls in his list of H. erectus fossils (which he considers human, p.350), and the smaller 2 Dmanisi skulls in his list of H. habilis fossils (p.352), which he considers to be apes.

So I have a question for Answers in Genesis. Why do they say that the smaller Dmanisi skulls belong to H. erectus and are human, if the man they recognize as the creationist expert on human evolution thinks they are apes?

In justifying their diagnosis, AIG quotes one of their other articles on human evolution, which claims:

The site of Dmanisi in the Republic of Georgia has produced four superb hominid skulls ranging in size from 600 cm3 to 780 cm3. These sizes range from the lower end of Homo erectus downwards into the Homo habilis range. The fossils contain a mixture of anatomical features from erectus and habilis. They could arguably be considered to belong either to primitive H. erectus (or H. ergaster), or to a new species, Homo georgicus. Vekua et al 2002 concluded:

The Dmanisi hominids are among the most primitive individuals so far attributed to H. erectus or to any species that is indisputably Homo, and it can be argued that this population is closely related to Homo habilis (sensu stricto) as known from Olduvai Gorge in Tanzania, Koobi Fora in northern Kenya, and possibly Hadar in Ethiopia.

These skulls are intermediate in both anatomy and size between Homo erectus and H. habilis, and as a result are exceedingly difficult for creationists to classify. Creationists therefore either ignored them (the usual reaction), or were forced into the absurdity of claiming that the biggest skull is human but the smallest two are apes (Lubenow 2004), or the almost equally implausible suggestion that all of them are human (Line 2005).

In 2007, further light was thrown on the Dmanisi hominids with the announcement that a substantial number of bones from below the skull had been discovered (Lordkipanidze et al 2007). These included a right femur, tibia and kneecap (the most complete known lower limb of early Homo); an ankle bone, part of a shoulder blade, three collar bones, three upper arm bones, five vertebrae, and a few other small bones. Some of these bones were associated with some of the previously discovered skulls.

Analysis of the bones shows that the Dmanisi hominids definitely walked bipedally and upright. However, the bones show a number of differences from modern humans and have some features associated with Homo habilis. The upper body differences lead the authors to suggest, with some caution, that “the Dmanisi hominins would have had a more australopith-like than human-like upper limb morphology”.

Their final conclusion was:

Euastacus sulcatus

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lamingtoncray.jpg

Euastacus sulcatus — Lamington spiny cray, Lamington Plateau, southeast Queensland, Australia

The Hobbit on Darwin Day

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A few months ago I attended a talk by Professor Colin Groves of the Australian National University: ‘An update on Homo floresiensis, a.k.a. the “Hobbit”’ (available on YouTube in seven installments: 1, 2, 3, 4, 5, 6, 7). As is well known, there has been an unusually bitter scientific debate over the last couple of years as to whether the hobbit is indeed a new species, or just a small microcephalic human. The term ‘microcephaly’ covers a range of conditions which cause unusually small brain sizes. (Disclaimer: Groves is not a disinterested participant in this debate, having coauthored a paper which argues against the microcephalic interpretation.) Groves went over a long list of unusual features of the hobbit. The limb bone ratios are unlike those of any apes or humans. They are also very robust: in spite of their small size, hobbits would have been remarkably strong. The arms are too long for humans, and they had unusually large feet (like Tolkien’s hobbits!). The lower jaw lacks a chin, a feature found in all humans (even people who look chinless), and that is also true of a second jaw which has been found. The upper end of the humerus has a twist not found in modern humans, but which was then found in the Turkana Boy Homo erectus/ergaster skeleton once it was looked for. Groves’ conclusion: all of these features make it overwhelmingly unlikely that the hobbit was just a small microcephalic human.

In the question time afterwards, I asked Groves whether the scientific community was coming to any consensus about the hobbit.

As we’ve pointed out before on the Panda’s Thumb, the proposed intelligent design textbook Of Pandas and People indicates that intelligent design was simply a rebadging of creationism. In view of that, let’s look at the short chapter of the 1993 edition of Pandas which discusses human evolution. Here are some quotes from that chapter:

Does the fossil record provide any evidence for either the Darwinian or the intelligent design view of man? (p.107)

Homo erectus had a larger brain (950cc) than Homo habilis, and walked with an upright posture, like man. … It had significant anatomical differences from modern man that have prevented its classification as Homo sapiens. (p.110)

Design adherents, however, regard Homo erectus, as well as the other hominids discussed in this section, as little more than apes, and point instead to the abrupt appearance of the culture and patterns of behavior which distinguish man from apes. (pp.112-3)

Who are these “design adherents” who regard Homo erectus as “little more than apes”?

We’ve talked here a few times about Utah state senator Chris Buttar’s wish to have a disclaimer about human evolution added to the state school board’s proposed position statement on teaching evolution:

Buttars believes the document should include new language: “There is not generally accepted agreement in the scientific community or (evidence) that has stood up to scientific scrutiny regarding the evolution of man from any other species.” (Deseret News, Aug 27 2005)

The reality is that there’s lots of good evidence for human evolution, including a number of habiline specimens that sit nicely midway between apes and humans. This doesn’t bother most creationists (like Buttars), because they’re blissfully unaware of them. Creationists often discuss Neandertals or Lucy at length, because it’s easy to dismiss them as humans and apes respectively, and pass over the habilines.

On his blog, William Dembski noted the appearance of a new Intelligent Design blog at the University of California Irvine, and suggested that the appearance of more such blogs would be "a Darwinist's worst nightmare".

Might I suggest instead that biologists (calling them 'Darwinists' is about as silly as calling chemists Daltonists) are more likely to fall about laughing? Take, for example, some reasoning from an early posting at the new blog:

Now here comes my intuitive (a.k.a. hand-waving) argument for design:
1. This fountain is elegant and complex.
2. The ducks are more elegant and more complex than the fountain.
3. If X is more elegant and more complex than Y, then X is more likely to be designed than Y.
4. The fountain was likely to be designed.
5. The ducks were more likely to be designed.

I haven't seen such compelling logic since the last time I saw another argument involving ducks: the witch scene from Monty Python and the Holy Grail. Really, the idea that this something like this constitutes evidence against evolution should be embarrassing even to IDers.

Update: As expected, the ID blog mentioned above has sunk into richly deserved oblivion...

I recently got a copy of the new 2nd edition of Marvin Lubenow's book Bones of Contention, a creationist book about the evidence for human evolution. I'll do a fuller review of it later, but there's one thing I want to comment on now. In 2002, the discovery of a new hominid skull from Dmanisi, Georgia, was announced. This skull had a very small brain size of 600 cc, in the Homo habilis range. Two other skulls which had been announced in 2000 had brain sizes of 650 cc and 780 cc. The skulls had a mixture of features from H. erectus and H. habilis and although the smallest one seemed slightly more primitive, the discoverers saw no reason not to put them all in the same species.

I found these skulls particularly interesting because they nicely straddle the gap that creationists like to claim separates humans from non-human primates. Generally the less-incompetent creationists (i.e. those who don't still think that Java Man and Peking Man are ape or monkey skulls) have a dividing line of about 700 cc; usually anything above that is human, and anything below it isn't. Although there are a couple of fragmentary habilis skulls estimated to be in the 650-700 cc range, there weren't any moderately complete hominid skulls between about 620 and 720 cc, so that became the "gap" separating humans from non-humans. But now we have three skulls from the same place, the same time, and of the same species, sitting smack on top of that gap - above, below, and in it. How, I wondered, would Lubenow handle it?

It's difficult not to laugh at the Discovery Institute, with their transparent attempts to pretend that they don't have a religious agenda, and their nonstop media spinning. Recently there's been the hilarity of the Kansas Board of Education hearings. Before that there was the claim by DI fellow Jay Richards, a philosopher and theologian, that he thought there was a problem with the theory of relativity, based on his reading of magazine articles. In Paul Myers' words, it's like "a circus where they've fired all the acrobats and animal trainers and it's clowns, clowns, clowns all the time".

It would all be very funny if it wasn't so serious. Even though ID may be dead in the water scientifically, it is a real threat to science education, and ID-friendly initiatives are popping up all over the United States.

All of which gives me an excuse to present the following cartoon, the caption of which seems appropriate. This is a classic Australian cartoon from 1933:

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