Literature

It has long been recognised that Darwinists love to propose adaptationist stories about the origins of particular traits. Very few of them have the word "spandrel" in their working dictionaries. The Neanderthal nose has been considered as an adaptive structure: there must be a reason why Neanderthals had such big noses.

This gent uses XXL tissues. (Source here)

Some years ago, during a study of Neanderthal skulls, Schwartz and Tattersall identified "two triangular bony projections jutting into the front of the nasal cavity from either side". This was considered significant.

"Jeffrey Laitman, an anatomist at Mount Sinai Medical Center in New York who has been studying Neanderthal anatomy, thinks the bony structures probably helped Neanderthals breathe the cold air of Ice Age Europe. The jutting projections, Laitman suggests, could have provided more surface area on which to lay down mucosal coverings to warm and humidify cold, dry air before it reached the throat and lungs. Previous studies have suggested that the large sinus cavities of Neanderthals served a similar function." (Source here)

So, the argument went, the extra surface area was a more efficient heat transfer mechanism, allowing air to be warmed and humidified more effectively before reaching the lungs. This benefit was of adaptive significance to the Neanderthals, and natural selection ensured that the genetic instructions for making these large noses were passed on to subsequent generations. In a Commentary essay, Laitman et al. (1996) thought they were on to something really important:

"The acquisition and processing of oxygen and its by-products the primary mission of any air-breathing vertebrate. Chewing, walking, reproducing, thinking are all fine, but first one has to breathe. Anthropologists sometimes seem to forget this; evolution never does." [snip]
"[. . .] the overall Neanderthal anatomy suggests a group that relied more heavily upon the nasal rather than the oral route for respiration then do living humans. These specializations were very possibly due to respiratory-related adaptations to their environment. [. . .]"
"Although the exact function(s) of mammalian paranasal sinuses remains unclear, and have indeed become the focus of much recent study, it is likely that in Neanderthals they played at least some part in an air-exchange process, perhaps in warming and humidifying cold and dry air."

Notwithstanding all this, some remained unconvinced about the "respiratory-related adaptations". Callaway writes:

"The Neanderthal nose has been a matter of befuddlement for anthropologists, who point out that modern cold-adapted humans have narrow noses to moisten and warm air as it enters the lung, and reduce water and heat loss during exhalation. Big noses tend to be found in people whose ancestor's evolved in tropical climates, where a large nasal opening helps cool the body."

These scholars regarded the Neanderthal nose as an anomaly. Their preferred explanation was that a big nose goes with a big mouth and a wide jaw. In their view, Neanderthal features were all big, and this was sufficient to explain the facial features.

"To put this theory to the test, [Nathan Holton] and University of Iowa colleague Robert Franciscus, measured facial dimensions in dozens of Neanderthals and humans, ancient and modern. By correlating changes in the size of nose width, the distance between canine teeth, and other features, the researchers could determine whether or not big mouths went with big noses."

The results do not confirm the hypothesis. The researchers "found a slight link between nose and mouth, but not enough to explain Neanderthal noses. However, another measurement - the degree to which the face juts forward - seemed a better match for nose width." This suggests a developmental constraint rather than an adaptation.

Why, then, do Neanderthals have faces that jut further out than humans? "They had them because earlier hominids had them," Houlton says. He laments the tendency of some anthropologists to "atomise the body", and explain each of its part as an exquisite adaptation to an environment.

One additional research finding puts a different light on the adaptationist story noted above: "Fortunately for Neanderthals, their inner noses were narrower than the openings suggest, and therefore well adapted to bone-chilling winters." The moral of this incident seems to be: do not trust adaptationists who "atomise" the body and propose just-so stories for particular elements. Organisms are not collections of discrete elements but should be considered holistically. Evolutionary biologists have drunk too deeply at the well of reductionism.

The paradox of a wide nasal aperture in cold-adapted Neandertals: a causal assessment
Nathan E. Holton and Robert G. Franciscus
Journal of Human Evolution, Article in Press | doi:10.1016/j.jhevol.2008.07.001

Abstract: Neandertals have been characterized as possessing features indicative of cold-climate adaptation largely based on ecogeographical morphological patterning found in recent humans. Interestingly, one character that deviates from this pattern is a relatively wide nasal aperture. The ecogeographical patterning of the nasal aperture in recent humans would predict instead that Neandertals should exhibit reduced nasal breadth dimensions. [. . .] The results of these analyses indicate a weaker association between intercanine breadth and nasal breadth than expected, and that more variation in nasal breadth can be explained through basion-prosthion length rather than anterior palatal breadth dimensions. Moreover, the ontogenetic development of anterior palate breadth does not correspond to the growth trajectory of the breadth of the nose. These results explain the apparent paradox of wide piriform apertures in generally cooler climate-adapted Neandertals without resorting to dentognathic constraints, and provide additional insight into both the adaptive and nonadaptive (i.e., neutral) basis for Neandertal facial evolution.

See also:

Callaway, E. Why did Neanderthals have such big noses?, New Scientist, 27 October 2008

Laitman, J.T., Reidenberg, J.S., Marquez, S. and Gannon, P.J., What the nose knows: new understandings of Neanderthal upper respiratory tract specializations, Proceedings of the National Academy of Sciences, 1996 93(20), 10543-10545.

Schwartz J.H. and Tattersall, I., Significance of some previously unrecognized apomorphies in the nasal region of Homo neanderthalensis, Proceedings of the National Academy of Sciences, 1996 93(20), 10852-10854.

According to Jeffrey L. Bada, marine chemist and origin-of-life researcher, "Stanley Miller was the father of origin-of-life chemistry. And he was the leader in that field for many decades [. . .]. It was the Miller experiment that almost overnight transformed the study of the origin of life into a respectable field of inquiry." From there, it entered the textbooks - and although the academic world moved on in its thinking, the textbooks never ceased to present Miller's findings as a major milestone in the quest for a natural origin of life. This research was analysed by Jonathan Wells in his Icons of Evolution and the textbooks were shown to have selectively reported the research and to have almost completely omitted reference to any of the academic critiques of Miller's work.

New tests on old samples reveal new reaction products but nothing to advance the "life assembled itself" paradigm (Source here)

Miller devoted his research activity to building on his 1953 foundations - but without a lot to show for it.

But Miller's ultimate goal, the creation of a living organism in a test tube, eluded him and other researchers. "Making the amino acids made it seem like the rest of the steps would be very easy," he said in a 1996 interview with Reuters. "It's turned out that it's more difficult than I thought it would be". (Source here)

Miller thought he was looking for the "little trick" that would allow amino acids to self-assemble further, but after a life-time's work might have concluded that a paradigm shift was needed. Other researchers developed the concept of self-assembly, notably Sidney W. Fox - the champion of "microspheres". Whereas Miller needed a wet atmosphere to form amino acids, researchers making proteins (forming peptide bonds between amino acids) needed localities that were dry. Miller himself saw the weaknesses of locating the action near a volcanic vent. It might be dry, but the heat energy would prohibit further self-assembly:

More recently, some scientists - such as German chemist Gunter Wachtershauser - have argued that life was more likely to have originated near submarine vents in chemical processes catalyzed by metals. "I have a very simple response to that," Miller said. "Submarine vents don't make organic compounds; they decompose them," because most of the crucial compounds are unstable at high temperatures." (Source here)

Jeffrey Bada, who was once a student of Miller, inherited Miller's archive of materials produced by his many experiments. With others, Bada used modern, more sensitive equipment to analyse the reaction products. He reports finding many new reaction products at levels too low to be detected by Miller, and particular attention is focused on the volcanic experiments.

"We identified 22 amino acids and five amines in the volcanic experiment, several of which had not been previously identified in Miller's experiments. Vials from the other two experiments were also reanalyzed and found to have a lower diversity of amino acids. The yield of amino acids synthesized in the volcanic experiment is comparable to, and in some cases exceeds, those found in the experiments Miller conducted."

A critique of the findings can be found here and here and a more broadly-based assessment is here.
To be realistic, most people in the academic world have moved on. They are looking elsewhere - in many different directions. This blog has drawn attention to some of the challenges and unsolved problems here and here, notably the total inability of researchers to move beyond chemistry to address the information content of all living things.
Rather than rehearse these arguments again, it might be more effective to draw attention to a recent debate between Richard Dawkins and John Lennox at Oxford's Natural History Museum. Melanie Phillips was there and asked Dawkins some probing questions. Among the responses was this:

"Dawkins told me that, rather than believing in God, he was more receptive to the theory that life on earth had indeed been created by a governing intelligence - but one which had resided on another planet. Leave aside the question of where that extra-terrestrial intelligence had itself come from, is it not remarkable that the arch-apostle of reason finds the concept of God more unlikely as an explanation of the universe than the existence and plenipotentiary power of extra-terrestrial little green men?"

It is now apparent that the hypothesis of "life assembled itself" is bankrupt. Most Origin-of-Life researchers realise this and acknowledge that they are dealing with an indescribably low probability occurrence. Some are prepared to move the problem away from planet Earth to some galactic haven where this improbable event actually occurred - leading eventually to intelligent life and their subsequent seeding of life on Earth. Those who are sympathetic to pangenesis, apparently including Richard Dawkins, at least recognise the problems for abiogenesis theories. I ask - when will this message get a proper place in the textbooks? How long will students be told that important discoveries are just around the corner? Why are students not being fed the truth about what abiogenesis research has actually achieved?

The Miller Volcanic Spark Discharge Experiment
Adam P. Johnson, H. James Cleaves, Jason P. Dworkin, Daniel P. Glavin, Antonio Lazcano, Jeffrey L. Bada
Science 321, 17 October 2008: 404. | DOI: 10.1126/science.1161527

Miller's 1950s experiments used, besides the apparatus known in textbooks, one that generated a hot water mist in the spark flask, simulating a water vapor-rich volcanic eruption. We found the original extracts of this experiment in Miller's material and reanalyzed them. The volcanic apparatus produced a wider variety of amino acids than the classic one. Release of reduced gases in volcanic eruptions accompanied by lightning could have been common on the early Earth. Prebotic compounds synthesized in these environments could have locally accumulated, where they could have undergone further processing [. . .]

See also:

Berardelli, P. Did Volcanoes Spark Life on Earth? ScienceNOW Daily News, 16 October 2008

Pease, R. New spark in classic experiments, BBC News, 16 October 2008

Phillips, M. Is Richard Dawkins still evolving? The Spectator, 23rd October 2008

A web-search on the "father of modern philosophy" reveals the name of the Frenchman Rene Descartes. He was totally opposed to the authority given to Aristotle by his peers. Knowledge is not something handed down by an individual or a group of enlightened thinkers: it has to be justified on its merits.

Descartes is remembered for the way he approached the problem: via doubt. He found reasons for doubting everything, but he realised that he could not doubt his own existence. Je pense, donc je suis has gone down in history as Descartes' way of laying a foundation stone. He went on to develop his ideas about the mind being distinct from the body (Cartesian dualism), the certainty of God's existence, the reality of the external world, and ultimately a unified view of everything. His relentless march of reason captured the imagination of many, and Descartes has been hailed as the champion of rationalism, pre-empting the Enlightenment vision by several generations.

Strange things happened to Descartes' body after his untimely death in Sweden. He was buried in 1650 in a churchyard near to Stockholm. 16 years later, his body was exhumed and conveyed in the darkness of night to the residence of de Terlon, the French ambassador. There, the bones were put in a copper coffin and preparations were made for the long journey to Paris. Before departure, some dismembering of the body took place. This was initiated by the ambassador, who

"had requested the authorities that he might himself be allowed, "religiously", to take possession of Descartes' right index finger, the bone "which had served as an instrument in the immortal writings of the deceased"."

Apparently, several other bones disappeared. "The Swedish family that became the proud owners of Descartes' skull - how, it is not clear - had it lovingly inscribed with Latin verses celebrating its significance as a souvenir of the beginnings of rationality. Successive owners added their own signatures and inscriptions testifying to their own 'faith' in the relic." According to the author of the book under review:

"By the time de Terlon's convoy set off for home, [. . .] fragments of the controversial thinker's earthly remains had already started to be dispersed, as admirers licitly and covertly acquired relics - souvenirs to be treasured and revered, and handed down through the generations."

Celebrating reason by acquiring relics of Descartes (Credit: S. Kambayashi)

Another bout of pilfering took place during the French Revolution.

"As reason replaced faith in the new French Republic, Lenoir rescued the bones of France's greatest rationalist from the church of St Genevieve in Paris [. . .]. Meanwhile, on the eve of the Terror, a French revolutionary committee decreed that the bones should be moved to the Pantheon - the new secular cathedral of the revolution - and a statue erected to Descartes' memory. [. . .]
Once again, the whereabouts of Descartes' bones become shrouded in mystery. It is not even clear that Lenoir's rescued remains were those of the father of rationalism. Nor is it clear what happened to them thereafter. They seem to have gone missing among the carefully documented treasures in Lenoir's museum."

What is to be made of the extraordinary hunger for a piece of Descartes' skeleton? Those who praised this champion of reason might be expected to repudiate superstition and the veneration of relics. There is a paradox here for us to consider. The reviewer and the author appear to have come to the same conclusion:

"For Shorto, his own fascination with this curious piece of narrative history is a mirror for the concerns of each and every one of us, bewildered by modernity and struggling to find meaning and belief in a confusing world. [. . .][His] suggestion is, I think, that we cannot escape from our felt need for faith and devotion, and that, deprived of religious relics we turn to secular forms of worship."

Modern-day atheists frequently present themselves as champions of reason (but never acknowledge that Christians see human rationality as a gift of God). They associate superstition with religion and present themselves as having left that behind. Although they have made enormous strides in creating secular cultures in the Western world, it is noteworthy that superstition, horoscopes and New Age practices are widespread. Rationalism as an agenda does not change mankind's innate "felt need" for something more meaningful. "Secular forms of worship" emerge with remarkable ease. Significantly, it is the Christian community that is far better at resisting superstition than the secularists!

"What Americans Really Believe," a comprehensive new study released by Baylor University yesterday, shows that traditional Christian religion greatly decreases belief in everything from the efficacy of palm readers to the usefulness of astrology. It also shows that the irreligious and the members of more liberal Protestant denominations, far from being resistant to superstition, tend to be much more likely to believe in the paranormal and in pseudoscience than evangelical Christians. (Source here)

Rationalists also make a big mistake when they think of the Deism of Enlightenment scholars as peripheral to their philosophical agenda. Descartes himself is illustrative of this. His foundation is often quoted: "I think, therefore I am", but where does that get us? How do we build on that? It does not take us very far! It was not how Descartes developed his Grand philosophical scheme. Descartes' Deism was needed to give validity to reason and to realism.

"He writes that the certainty of his own existence is the "first principle" of his philosophy. But this just turns out to mean that it is the first certainty that he decided to accept, not that anything else is based upon it. Actually, Descartes infers nothing from his own existence. Instead, he asks how he comes to possess this one certainty, so that he can then find other certainties in the same way. The secret of that certainty is just that it involved "a clear and distinct perception of what I am asserting." Crucially, Descartes then introduces God. He offers several arguments for the existence of God, and, having satisfied himself that there must be a God, he reasons that this God, being good, would not allow His creatures to be seriously deceived, provided that they exercise some restraint and confine their beliefs to what they "clearly and distinctly" perceive to be true. Thus Descartes' system of knowledge depends not on his own existence but on God's." (Source: Gottlieb, 2006)

This becomes crucially important when people present science as a secularised Enlightenment project. The problem is: our senses are being asked to do something that can be justified if we presuppose foundations that cannot be justified by our senses alone: intelligibility, realism, rationality. Descartes and the Enlightenment thinkers needed Deism to do this. Today, it is only the Theist or the Deist who can build a philosophically coherent framework for science. Steve Fuller's comment is very much to the point:

"To be sure, scientific progress is sometimes portrayed as the distinctly human extension of this general evolutionary proclivity. But this is to miss entirely the point of science, which is to do with a unified understanding of all reality, not just the specific bits that permit specific groups reproductive advantage. Science does not make sense unless reality possesses a depth that eludes our normal sensory encounters with the world but can nevertheless be accessed with sufficient application under the right conditions. Thus, science presupposes the intelligibility of reality; that its organisation, whatever its ultimate cause, is tractable to the human mind. Evolutionists have been much quicker to explain religion than science itself, yet it is the latter that should worry them, given the peculiar combination of mental dispositions needed to sustain scientific enquiry." (pages 44-45).

Relics of the modern mind
Lisa Jardine
Nature 455, 863-864 (16 October 2008) | doi:10.1038/455863a

BOOK REVIEWED - Descartes' Bones: A Skeletal History of the Conflict Between Faith and Reason, by Russell Shorto, Doubleday: 2008. 320 pp.

See also:

Fuller, S. Dissent over Descent, Icon Books Ltd., Cambridge, 2008.

Gottlieb, A. Think again, New Yorker, 2006-11-20

It has often been noted that Darwinian mechanisms could not operate prior to the first presumed replicating cell. Without replication, there can be no selection - or can there? This is the conundrum addressed by Nowak and Ohtsuki in their attempt to "formulate a general mathematical theory for the origin of evolution". These authors recognise that the origin of the first replicating cell must have had a sophisticated precursor, because otherwise the jump in complexity would have been too great.

"We have proposed a mathematical theory for studying the origin of evolution. Our aim was to formulate the simplest possible population dynamics that can produce information and complexity. We began with a "binary soup" where activated monomers form random polymers (binary strings) of any length. Selection emerges in prelife, if some sequences grow faster than others. Replication marks the transition from prelife to life, from prevolution to evolution. Prelife allows a continuous origin of life."

A prebiotic chemistry is proposed with activated monomers denoted by 0 or 1 (Source here)

As in all simulations, the model has to involve simplifications. First, the authors propose a primordial soup with monomers as active ingredients. These entities have the potential for generating "unlimited information".

"Let us consider a prebiotic chemistry that produces activated monomers denoted by 0* and 1*. These chemicals can either become deactivated into 0 and 1 or attach to the end of binary strings. We assume, for simplicity, that all sequences grow in one direction. [. . .] Each sequence is produced by a particular lineage that contains all of its precursors. In this way, we can define a prebiotic chemistry that can produce any binary string and thereby generate, in principle, unlimited information and diversity. We call such a system prelife and the associated dynamics prevolution."

It is significant that the authors draw attention to "unlimited information" potential, rather than random sequence generation. But biological information requires much more than a specified bit string! Numerous people have wrestled with the thought that the genetic code needs to be translated if it is to have any biological function. Base sequences are no different from junk if there is no machinery to turn the code into something biologically meaningful - and all the machinery that we are aware of is extraordinarily complex. For more on this, go here. Even allowing that sequences could have emerged containing information in code form, we have not progressed conceptually beyond the typing monkey scenario.

The bit sequences are considered to be formed at a quantifiable speed, and it is also premised that the tempo of decay is quantifiable. "Selection emerges in prelife, if different reactions occur at different rates." In this model, the concept of selection is based on the longevity of sequences that spontaneously form in the soup. This use of the word "selection" is confusing, because there is no sense in which one sequence competes against other sequences and demonstrates fitness in the primordial ecology. The authors claim that the information carriers "compete for resources" but this is not convincing. Resources are relevant to the growth of the sequences, but not to the time before they decay. There is nothing about the longer-lasting sequences that can be related to environmental selection.

"Traditionally, one thinks of natural selection as choosing between different replicators. Natural selection arises if one type reproduces faster than another type, thereby changing the relative abundances of these two types in the population. Natural selection can lead to competitive exclusion or coexistence. In the present theory, however, we encounter natural selection before replication. Different information carriers compete for resources and thereby gain different abundances in the population. Natural selection occurs within prelife and between life and prelife. In our theory, natural selection is not a consequence of replication, but instead natural selection leads to replication. There is "selection for replication" if replicating sequences have a higher abundance than nonreplicating sequences of similar length. We observe that prelife selection is blunt: Typically small differences in growth rates result in small differences in abundance."

There are many more issues of simplification that could be explored. However, enough has been said above to justify the conclusion that this paper does not deserve any more attention until the model is validated. This the authors have avoided doing. They make no attempt to justify their assumptions by reference to current thinking about abiogenesis. They say nothing about the importance of testing the model and validating the findings. This is a great weakness of many research programmes based on simulation, where the authors live in virtual reality and think that because they can model it, there is some substance in their work. One could say exactly the same about simulations of evolution: they may have a use in getting across theoretical concepts but they have no established link with the real world.

The media reporting of this paper suggests hype is in the air. Here is the subtitle from Scientific American: "How did self-replicating molecules come to dominate the early Earth? Using the mathematics of evolutionary dynamics, Martin A. Nowak can explain the change from no life to life". The reader is being invited to conclude that Nowak has answers supported by maths, not that he has an entirely tentative hypothetical model, full of unsubstantialted assumptions. Another example comes from the pen of Roger Highfield. He emphasises the suggestions emerging from the research, as though it provides a foundation on which to build. It would be more realistic to portray the proposed scenario as virtual reality, urgently needing a heavy dose of scientific realism:

"An analysis suggests that the soup of chemicals on the early Earth was naturally evolving towards creating the first life, a discovery that suggests alien life should be common. A mathematical analysis of how simple chemicals crossed the threshold between dead and living suggests that natural selection that gave us the vast diversity of life on the planet, from bacteria to tigers, was at work in the primordial Earth too."

According to Nowak: "Mathematics is the proper language of evolution. I don't know what the 'ultimate understanding' of biology will look like, but one thing is clear: it's all about getting the equations right." Getting the equations right is exactly what this blog is about. The scientific approach is to model real-world systems and test the ability of the model to replicate reality. Nowak's danger is giving the impression he has made a contribution to scientific knowledge without making any attempt to validate his model.

Prevolutionary dynamics and the origin of evolution
Martin A. Nowak and Hisashi Ohtsuki
Proceedings of the National Academy of Sciences, Published online before print September 12, 2008, doi: 10.1073/pnas.0806714105

Abstract: Life is that which replicates and evolves. The origin of life is also the origin of evolution. A fundamental question is when do chemical kinetics become evolutionary dynamics? Here, we formulate a general mathematical theory for the origin of evolution. All known life on earth is based on biological polymers, which act as information carriers and catalysts. Therefore, any theory for the origin of life must address the emergence of such a system. We describe prelife as an alphabet of active monomers that form random polymers. Prelife is a generative system that can produce information. Prevolutionary dynamics have selection and mutation, but no replication. Life marches in with the ability of replication: Polymers act as templates for their own reproduction. Prelife is a scaffold that builds life. Yet, there is competition between life and prelife. There is a phase transition: If the effective replication rate exceeds a critical value, then life outcompetes prelife. Replication is not a prerequisite for selection, but instead, there can be selection for replication. Mutation leads to an error threshold between life and prelife.

See also:

Coppedge, D.F. The Prevolution of Evolution: Life Marches In, Creation-Evolution Headlines, 09/17/2008

Highfield, R. Soup of chemicals on primordial Earth was naturally evolving toward life, The Daily Telegraph, 17/09/2008

Wax, H. Using Math to Explain How Life on Earth Began, Scientific American, October 2008.

Cichlid fish have been called "a crucible for evolution studies". Lake Victoria, in Eastern Africa, contains over 500 species of cichlid fish - all members of the same distinctive family, but differing in numerous details of morphology, behaviour and genetics. Since these species can reasonably be inferred to be linked by common ancestry, they are ideal targets for speciation research. Since many of these fish occupy similar ecological niches within the lake, sympatric speciation mechanisms (not involving geographical isolation) have been considered highly probable.

Speciation - something to shout about? (source here)

The new research focuses on light: colouration and factors affecting vision.

"Water clarity and ambient light vary considerably throughout the lake, and fish of many species range in colour. In shallow parts, blue light is dominant, and the waters are populated by blue males of the species Pundamilia pundamilia. As the water deepens, red light becomes increasingly dominant, and greater numbers of red-coloured males of the species Pundamilia nyererei are seen."

The key finding has been an association between ambient light, the colour of the fish and the genetics of colour vision.

"We found a strong association between the visual gene and fish colour," says Seehausen. "Red fish have the gene that shifts vision towards picking up red light, and the blue fish have visual genes that pick up blue light."

This association, although not surprising, is significant for understanding the ecology of the cichlids. Jenny Boughman, an evolutionary biologist, is quoted as saying: "They show a clear segregation between what the fish see, their colour and where they live." The inference follows that visual sensing plays a significant part in male selection. The authors have not argued a convincing case here:

"But [Boughman] says more work is needed, such as evidence that shows it is the difference in female vision that causes them to pick the differently coloured males. Only that, she argues, would prove that vision is driving the speciation."

Nevertheless, a start has been made: "The group also found that some females with blue-biased vision prefer to mate with blue males, and red-biased females mate with red males [. . .]." But these preferences on the part of some animals falls short of rigorous documentation and the species mechanism is still at the level of hypothesis.

So, what has been achieved? Is this a textbook example of evolution? All the reports of this research emphasise the observations that have been made, and it is correct to say that these observations confirm an association of vision-related parameters. Crucial observations of mating behaviour are in short supply and there are no direct observations of speciation. Yet the Nature summary claims the research provides "clear evidence that speciation can occur through sensory drive without geographical isolation". Nature News is more realistic in its assessment: "The new work is the strongest evidence yet that differences in sensory input - in this case, vision - can give rise to new species."

"The strongest evidence yet" involves a correlation between the visual system, body colour and ecology. Instead of this being used to support a hypothesis of sexual selection based on body colouration, the authors claim to have demonstrated sexual selection in action. This has been picked up by the media as fact: "a fish species in the cichlid family has been observed by scientists in the act of splitting into two distinct species in Lake Victoria" (Source). The cover of Nature proclaims that this is "a textbook example of evolution in action".

Let us suppose that the hypothesis is tested and confirmed, and the "sensory drive speciation" is validated. What are the implications for our understanding of evolution? It means that an ancestral fish population can split into two or more populations on the basis of colour. The daughter populations have differences in sensitivity to light frequencies and differences in body colouration. These may be accompanied by other ecological adaptations. There is no new genetic information - just fine-tuning of existing genetic systems. There is no evidence that these new species lack the potential to interbreed. Indeed, the differences are so slight that hybridisation to produce fertile offspring can be predicted with some confidence.

The claim of "evolution in action" will mean different things to different people. To ID scientists, it means that relatively trivial variations can and do occur in living things. These variations allow organisms to diversify and prosper in new ecological niches as they become accessible. However, these variations have nothing to do with the origin of cichlids, eyes or complex specified information. To most evolutionary biologists, apparently, it means that all the big questions of biological origins can, in principle, be solved. If we can demonstrate speciation in action, then we can rest assured that we also have an explanation of the origins of families, orders, phyla, organs and organelles. Evolutionary biologists can then repeat the mantra that nothing in biology makes sense without evolution.

The punchline: ID scientists are not opposed to the teaching of evolution in schools, but want it taught properly - allowing critical appraisal and the recognition of spin. Let speciation in cichlid fish enter the textbooks, not as a proof of evolution, but as an example of how evidence is brought to bear on current hypotheses of the origin of species.

Speciation through sensory drive in cichlid fish
Ole Seehausen, Yohey Terai, Isabel S. Magalhaes, Karen L. Carleton, Hillary D. J. Mrosso, Ryutaro Miyagi, Inke van der Sluijs, Maria V. Schneider, Martine E. Maan, Hidenori Tachida, Hiroo Imai & Norihiro Okada
Nature 455, 620-626 (2 October 2008) | doi:10.1038/nature07285

Abstract: Theoretically, divergent selection on sensory systems can cause speciation through sensory drive. However, empirical evidence is rare and incomplete. Here we demonstrate sensory drive speciation within island populations of cichlid fish. We identify the ecological and molecular basis of divergent evolution in the cichlid visual system, demonstrate associated divergence in male colouration and female preferences, and show subsequent differentiation at neutral loci, indicating reproductive isolation. Evidence is replicated in several pairs of sympatric populations and species. Variation in the slope of the environmental gradients explains variation in the progress towards speciation: speciation occurs on all but the steepest gradients. This is the most complete demonstration so far of speciation through sensory drive without geographical isolation. Our results also provide a mechanistic explanation for the collapse of cichlid fish species diversity during the anthropogenic eutrophication of Lake Victoria.

See also:

Kirkpatrick, M. & Price, T. Sensory ecology: In sight of speciation, Nature 455, 601-602 (2 October 2008) | doi:10.1038/455601a

Gilbert, N. What you see is how you evolve, Nature News, 1 October 2008 | doi:10.1038/news.2008.1144

One of the more notable fossil finds this year concerns a juvenile gecko lizard, less than an inch long, parts of which were preserved in amber. The researchers have studied a posterior lower limb and foot, and a partial tail. "The discovery has been announced as a new genus and species of gecko, now extinct, and has been named Cretaceogekko. It had a striped pattern that probably served as camouflage."

The tiny foot of Cretaceogekko: a Cretaceous species with modern sophistication. (Image here)

The find is remarkable on two counts. The first is that this specimen nearly doubles the reported age of the oldest known fossil gecko. The previous record was Lower Eocene, but the new find takes us back well into the Age of Dinosaurs. Today, there are about 2000 species of gecko, allocated to nearly 100 genera. There is therefore great natural variability in the group, and it is not surprising that the fossil should be assigned to a new genus. Stasis at the family level is demonstrated: the Gekkonidae have been stable over geological time. This is an observation that needs greater emphasis in education about the history of life on Earth. Evolutionists are so keen to focus on small variations that they miss the big picture, which is that stasis, rather than transformation, characterises the fossil record.

Secondly, the researchers report the presence of "sophisticated adhesive toe pads". The pads on the toes were observed to have "transverse lamellae probably bearing numerous hairlike setae found in many modern geckos".

"The tiny foot of this ancient lizard still shows the tiny "lamellae," or sticky toe hairs, that to this day give modern geckos their unusual ability to cling to surfaces or run across a ceiling. Research programs around the world have tried to mimic this bizarre adhesive capability, with limited success." [For more on recent research, go here].

A good case can be made for gecko setae being irreducibly complex as an aggregated structure. A few setae are useless - there is no significant adhesion. There is no rationale for setae to accumulate on the feet of ancestral geckos, because there is no identifiable functionality unless the assembly is a fully formed. Merely having setae is not enough either, as is clear from the difficulties of producing biomimetic products. If intelligent agency is having a hard time emulating the gecko mechanism for adhesion, it is not unreasonable to ask whether intelligent agency was involved in designing and engineering the real thing. In support of the irreducible complexity argument, it is significant that these toe pads are fully formed in the very oldest specimen known to us. We do not see any transitional structures. This creates an enormous problem for theories of gradual transformation, which must defend a step-by-step route for climbing Mount Improbable. Geckos appear fully formed, and it is the Darwinists that are found contending with the data in order to preserve their theory.

A 100 million year old gecko with sophisticated adhesive toe pads, preserved in amber from Myanmar
E. Nicholas Arnold & George Poinar
Zootaxa, 1847: 62-68 (11 Aug. 2008)

Abstract: A new genus and species of gecko is described from a posterior lower limb and foot, and a partial tail, preserved in Lower Cretaceous amber from Myanmar that is 97-110 My old. It appears to be the oldest unequivocal fossil gecko, predating fragmentary skeletal remains from the Upper Cretaceous and being 43-56 My older than Yanatarogecko from the Lower Eocene, previously the oldest known gecko preserved in amber. It also provides firm evidence that gekkotans and possibly gekkonids were in Asia at this time. The Myanmar specimen shows, that the distinctive foot proportions and sophisticated adhesive mechanism, involving pads on the toes with transverse lamellae probably bearing numerous hairlike setae found in many modern geckos, had already evolved around 100My ago. The specimen is very small, even compared with juveniles of the smallest living geckos. However, the high numbers of lamellae on its toe pads suggest it is from a juvenile of a species with relatively large adult body size.

See also:

Oldest Gecko Fossil Ever Found, Entombed In Amber, ScienceDaily (Sep. 3, 2008)

Tyler, D. Gecko feet set the standard for adhesion, ARN Literature Blog (25 July 2007)