Explosion of the Blob
Some scientists are looking into the folds of a sponge for clues about the Cambrian Explosion – the sudden emergence of all the major body plans in the geological blink of an eye. What they are finding is more complexity than a first glance at the simple creatures would expect.
A draft genome of a demosponge named Amphimedon from the Great Barrier Reef has just been published. Adam Mann wrote about this in Nature News,1 hinting at the divination going on: “Researchers wring evolutionary clues from gene sequence.” One result so far, he said, is “Telltale molecular fragments teased out of ancient sediment show that sponges existed some 635 million years ago – the oldest evidence for metazoans (multicellular animals) on Earth.”
The sponge has some 18,000 genes. This “represents a diverse toolkit, coding for many processes that lay the foundations for more complex creatures.” What kind of tools? “These include mechanisms for telling cells how to adhere to one another, grow in an organized fashion and recognize interlopers.” In what may sound very surprising for such a lowly creature, “The genome also includes,” Mann continued, “analogues of genes that, in organisms with a neuromuscular system, code for muscle tissue and neurons.” Why would a sponge have such genes without having a neuromuscular system or central nervous system? He didn’t say.
Mann suggested that the discovery of this complexity in a sponge genome forces the evolution of complexity back in time: “such complexity indicates that sponges must have descended from a more advanced ancestor than previously suspected.” He quoted Douglas Erwin of the Smithsonian responding with alarm that “This flies in the face of what we think of early metazoan evolution.” Charles Marshall, the master of Cambrian Explosion disaster (see 04/23/2006), added, “It means there was an elaborate machinery in place that already had some function. What I want to know now is what were all these genes doing prior to the advent of sponge.”
The sponge genome was published by Srivastava et al in the same issue of Nature.2 Mann summarized its conclusions as an invocation of the power of emergence by unknown powers of evolution operating in a critical window of time. During that time, nefarious processes that would plague humans 635 million years later, like a kind of ruthless communism, were being laid:
The analyses of Srivastava and her colleagues suggest that there was a crucial window, some 150 to 200 million years in duration, when the basics of multicellular life emerged. Nearly one-third of the genetic alterations that distinguish humans from their last common ancestor with single-celled organisms took place during this period. These changes would have occurred within our sponge-like forebears.
The researchers also identified parts of the genome devoted to suppressing individual cells that multiply at the expense of the collective. The presence of such genes indicates that the battle to stop rogue cells ? in other words, cancer ? is as old as multicellularity itself. Such a link was recently hinted at by work showing that certain ‘founder genes’ that are associated with human cancers first arose at about the same time as metazoans appeared. The demosponge genome shows that genes for cell suicide – those activated within an individual cell when something goes wrong – evolved before pathways that are activated by adjacent cells to dispatch a cancerous neighbour.
By saying that nearly one-third of the genetic toolkit “emerged” in a blank period before the fossils of the first actual sponge, and that the changes “occurred” in undescribed “sponge-like forebears,” Mann shielded the fact that there is not only no evidence for such an ancestor, but no known mechanism by which genes with foresight would have emerged in single-celled creatures.
Srivastava et al were no help explaining how this emergence occurred. A search on evolution in the paper reveals these circumlocutions:
- Comparative analysis enabled by the sequencing of the sponge genome reveals genomic events linked to the origin and early evolution of animals, including the appearance, expansion and diversification of pan-metazoan transcription factor, signalling pathway and structural genes. This diverse ‘toolkit’ of genes correlates with critical aspects of all metazoan body plans, and comprises cell cycle control and growth, development, somatic- and germ-cell specification, cell adhesion, innate immunity and allorecognition.
- The emergence of multicellular animals from single-celled ancestors over 600 million years ago required the evolution of mechanisms for coordinating cell division, growth, specialization, adhesion and death.
- Sponges are diverse and their phylogeny is poorly resolved, allowing for the possibility that sponges are paraphyletic, which implies that other animals evolved from sponge-like ancestors.
- Although the diversity of sponges and their uncertain phylogeny make it doubtful that any single species can reveal the intricacies of early animal evolution, comparison of the A. queenslandica draft genome with sequences from other species can provide a conservative estimate of the genome of the common ancestor of all animals and the timing and nature of the genomic events that led to the origin and early evolution of animal lineages.
- We find 235 animal-specific protein domains and 769 animal-specific domain combinations that evolved along the metazoan stem (Supplementary Note 9). Additionally, lineage-specific changes to these animal domain architectures occurred in early metazoan evolution.
- The Myc oncogene illustrates how intramolecular regulation has also evolved.
- This lack of phylogenetic resolution may reflect a period of rapid evolution and diversification of ligand/receptor molecules in sponge and eumetazoan lineages.
- …the expression of orthologues of post-synaptic structural and proneural regulatory proteins in Amphimedon larval globular cells suggests an evolutionary connection with an ancestral protoneuron.
No such protoneuron is known, of course, but in the Conclusion section, the question of how this complexity originated was asked directly. The answer was shrouded in passive voice verbs and unstated mechanisms:
Whereas the eumetazoan lineage produced a wide diversity of body forms [i.e., the Cambrian Explosion], the sponge body plan has been stable for over 600 million years. What can explain this disparity in evolved morphological complexity? Although we have seen that sponges and eumetazoans share many common pathways related to morphogenesis and cell-type specification, there are notable genomic differences, including different microRNA assemblages, lineage-specific domains and domain architectures, and the differential expansions of gene families. Although there has been minimal characterization of cis-regulatory architectures in non-bilaterians, we note that as most classes of bilaterian transcription factors are also present in sponges, cnidarians and placozoans, it may be that quantitative rather than qualitative differences in cis-regulatory mechanisms were needed to produce more diverse body plans.
The sexually-reproducing, heterotrophic metazoan ancestor had the capacity to sense, respond to, and exploit the surrounding environment while maintaining multicellular homeostasis. Although sponges lack some of the cell types found in eumetazoans, including neurons and muscles, they share with all other animals genes that are essential for the form and function of integrated multicellular organisms. With these genomic innovations enabling the regulation of cellular proliferation, death, differentiation and cohesion, metazoans transcended their microbial ancestry.
They just said, in brief, that all the genetic toolkit was there in the sponge ancestor. The Cambrian Explosion was due to “quantitative rather than qualitative differences” in the tools. But does this explain a trilobite, a segmented worm, shellfish, crabs, the predator Anomalocaris, and all the other amazing creatures found at the point of the Cambrian explosion? And why would a microbe come up with these tools in the first place, even to produce a sponge?
New Scientist put the solution to the Cambrian explosion in terms of hope and change: “Now that their genetic make-up has finally been sequenced, it could explain one of the greatest mysteries of evolution: how single-celled organisms in the primordial oceans evolved into complex multicellular animals with the spectacular diversity of body plans we see today.”
As with the Nature articles, though, the explanation consisted of saying little more than complexity was already there: “This means that all the key genetic prerequisites for modern animals made up of trillions of cells were in place well before sponges split from other animals 600 million years ago.” Somehow, we are told, sponges moved up from microbes to become inventors: “To this basic set of genes, sponges and other multicellular animals add a small suite of master-control genes which may allow the greater coordination needed when several cells are dividing together.” Science Daily, likewise, admitted that “how this differential complexity is encoded in the genome is still a major question in biology.” A coauthor of the study, Bernie Degnan, a professor of biology at the University of Queensland, Australia, engaged in ancestor worship. “This incredibly old ancestor possessed the same core building blocks for multicellular form and function that still sits at the heart of all living animals, including humans. It now appears that the evolution of these genes not only allowed the first animals to colonize the ancient oceans, but underpinned the evolution of the full biodiversity of animals we see today.” They evolved because they evolved.
Moreover, Degnan told Science Daily that “all the genomic innovations that we deem necessary for intricate modern animal life have their origins much further back in time that anyone anticipated, predating the Cambrian explosion by tens if not hundreds of millions of years.” He was stunned by the revelations coming from the genetic crystal ball: “Remarkably, the sponge genome now reveals that, along the way toward the emergence of animals, genes for an entire network of many specialized cells evolved….”
However they evolved, Degnan admitted that human engineers look to the sponge for inspiration for their own designed innovations. “Sponges produce an amazing array of chemicals of direct interest to the pharmaceutical industry,” the quote in Science Daily continued. “They also biofabricate silica fibers directly from sea water in an environmentally benign manner, which is of great interest in communications. With the genome in hand, we can decipher the methods used by these simple animals to produce materials that far exceed our current engineering and chemistry capabilities.” (See 11/20/2008 and its embedded links for descriptions of the exquisite fiber-optic structures produced by some sponges.)
Tantalizing glimpses of a primordial sponge blob were revealed by PhysOrg: “Ancient blob-like creature of the deep revealed by scientists.” Scientists at Imperial College London generated a 3D image of Drakozoon, the only known fossil specimen of a “cone-shaped, blob-like creature with a hood” that “probably had a leathery exterior skin.” “We think this tiny blob of jelly survived by clinging onto rocks and hard shelled creatures, making a living by plucking microscopic morsels out of seawater,” said Dr. Mark Sutton, another diviner. “By looking at this primitive creature, we also get one tantalising step closer to understanding what the earliest creatures on Earth looked like.” But wait – Drakozoon was dated to 425 million years old, making it far too late to be the mysterious 635-million-year-old proto-sponge with all the tools needed to build a human. The clever innovator remains shrouded in the presumptions of a long-lost evolutionary past.
1. Adam Mann, “Sponge genome goes deep,” Nature News, published online 4 August 2010, Nature 466, 673 (2010), doi:10.1038/466673a.
2. Srivastava et al, “The Amphimedon queenslandica genome and the evolution of animal complexity,” Nature 466, pp 720?726, 05 August 2010, doi:10.1038/nature09201.
Are you angry after reading this? You should be. Ever since Charlie’s coup, the world has been told that evolution is the one-and-only scientific explanation for the living world. It’s all smoke and mirrors! Look at what they said – complexity just emerged in the genes of some hypothetical, unseen, mythical “common ancestor.” (Note the imbedded evolutionary assumption there and the euphemism for miracle, emergence). This ancestor was endowed with such incredible foresight, it somehow came up with “innovations” that would prove useful to the scientists 636 million years later who might want to use their neurons to write nonsense. What? Getting even one useful gene is astronomically improbable (online book), to say nothing of 18,000 genes matching in a functional “genetic toolkit.” This is absolutely shameful. It’s indescribably absurd. Science is supposed to be about evidence, observations, data, testability, repeatability, proof, not just hollow thinking of ideologues, writing about magic visions reflecting in the vitreous humor of their darkened eyeballs.
All the tricks of the racketeer are here. Readers are shielded from contrary evidence and critical analysis (card stacking). The nonsense is wrapped in the prestige of science (association). Everywhere questions are begged (circular reasoning) in broad-brush statements (glittering generalities), while key issues, like how complexity “emerged,” are dodged in passive verbs and miracle words (sidestepping). The lingo is loaded with bluffing and subjectivity and equivocation. non-sequiturs abound, such as the inference that complexity in sponge cells implies that thousands of genes exist in some putative microbe ancestor, based on circumstantial evidence interpreted according to an a priori commitment to naturalism (post hoc fallacy, it exists, therefore it evolved). This has nothing to do with science; this is dogma in an echo chamber (repetition). And when the lack of evidence is too overpowering to ignore, there’s always hope that the evidence “may shed light” on evolution (suggestion).
Folks, we are not talking about some little, backwater issue with Charlie’s grand scheme, but the main argument even Darwin admitted could be deadly to his theory – the lack of evidence for transitional forms at the base of the fossil record (Origin, chapter 10). It was unsolved in his day; it remains unsolved today. In fact, it is far worse for evolutionists now than it was in 1859, because there are no more excuses that the fossil record is incompletely sampled, or that Precambrian rocks could not preserve soft tissues (see the film Darwin’s Dilemma). Look at the flim-flam offered up a few years ago by Charles Marshall, the Master of Disaster, when tasked with explaining the Cambrian explosion (04/23/2006): basically, “it evolved because it evolved”. This is smoke, not science.
The fossil record, a spear-pointed battering ram aimed at the flimsy gate of evolutionary theory, should have toppled King Charlie’s castle long ago. It’s not for lack of trying. Critics have used the battering ram to good effect from the beginning, but Charlie’s demons maintain an impenetrable moat of smoke to hide the sacred image of the Bearded Buddha in the castle temple. Long ago, they co-opted all the institutions – the journals, the media, schools and even some churches – keeping them occupied perpetuating the smoke moat with their fogma machines, sending the sensible soldiers with the battering ram coughing and the Darwincense-addicted Charlie worshippers inhaling deeply, euphoric in their hallucinations of “emergence.” (For definition of fogma, see the 05/14/2007 commentary.) The defenders of the castle are also well-trained in hate speech, knowing to close their eyes, cover their ears, and shout on cue “Creationism! Pseudoscience!” at any sign of the battering ram.
The Bearded Buddha is a false god. It’s long past time to clear the air and demand scientific integrity. Don’t get angry; get the power fans. Once the truth can be seen, a battering ram will not even be necessary. The Darwin Castle will vanish in its own fogma. Expect a hard fight getting the power fans in place, though; there’s too much riding on this ideology. Expect Screwtape to use his whole arsenal in its defense.