Does the “world’s oldest sponge” shed light on our evolutionary history or the earliest days of our floody past?
DailyMail.com: “World’s Oldest Sponge Unearthed: ‘Nearly Pristine’ 600 Million-Year-Old Fossil Pushes Back the Date for Animal Evolution”
A “nearly pristine” Precambrian sponge fossil—the size of a tiny bead—has been recovered from China’s Doushantuo Formation. About a millimeter across, Eocyathispongia qiania is not just a flattened trace or fragment but is preserved in three dimensions, essentially frozen in time.
The fossil came from the uppermost layer of this Precambrian rock unit, supposedly deposited 600 million years ago during the Ediacaran Period. With its exquisite details preserved by phosphorus-rich sediment, modern imaging technology reveals hundreds of thousands of cells in the fossil and a very modern-looking sponge anatomy.
This Precambrian fossil has the same overall anatomy and cell types found in sponges today. It consists of three tube-shaped chambers extending from a common base. The main tube is topped with a funnel-like opening, and the others open to the outside with a typical sponge’s osculum. Covering the outer surface are lots of small pores between flat cells that look like the pinacocytes covering modern sponges. There is a dense patch that looks like papillae that project from the surfaces of some sponges. Inside one tube is an array of regularly shaped pits, many topped with raised collars reminiscent of the collar cells that modern sponges use to draw food-laden water though their hollow bodies.
Though previously purported Precambrian sponges have met with skepticism,1 the authors report in Proceedings of the National Academy of Sciences that images of this one are quite convincing:
The fossilized animal, about 2–3 mm3 in size, was composed of easily recognizable cells. It displays the unmistakable gross anatomy of an adult sponge-grade animal, but beyond this finding, several distinct cell types and cellular structures can be clearly recognized.2
While “discovery of additional specimens would confirm that the fossil represents a Precambrian sponge” according to lead author Maoyan Zhu, “features of the fossil are consistent with sponge anatomy.” His group will be sifting through more material from the Doushuantuo Formation in search of more sponges and any other multicellular organisms that might be preserved there, for “fossils of similarly advanced eumetazoans [all major animal groups except sponges] may yet lie in the fossil record.”3
While Precambrian fossils are both sparse and small,4 this is not the first found displaying anatomical complexity. For instance, a cnidarian flexing its tiny muscles was recently discovered in Canadian Ediacaran rock dated at 560 million years.5 And the Doushantuo Formation’s Ediacaran rock is host to fossils originally thought to be animal embryos but later identified as spore clusters. Megasphaera, another complex microfossil from the Doushantuo Formation, contains “matryoshkas”—orderly arrangements of nested cells in envelopes. Though Megasphaera’s identity is still a matter of debate, it does not resemble a sponge.
Thus, while this is not the first “advanced” Precambrian microfossil to be discovered, Eocyathispongia qiania is the first to look so unmistakably like a sponge. And many evolutionists believe sponges are the most primitive animals.
Evolutionists project that sponges and the lineage leading to all other multicellular animals diverged from their last common ancestor about 200 million years before the Cambrian explosion.6 This extrapolation comes from molecular clock dating and a connect-the-dots exercise superimposing evolutionary presuppositions atop observable genomic comparisons. However, as the discoverers of Eocyathispongia write, the fossil record has not affirmed these evolutionary extrapolations:
Despite phylogenomic extrapolations that indicate divergence of sponge lineages from eumetazoan lineages deep in Precambrian time, lack of substantial paleontological evidence directly supporting this prediction has thus remained frustrating.7
Precambrian strata have not only failed to corroborate these evolutionary extrapolations but also to supply the necessary transitional Precambrian ancestors for the animals in the Cambrian explosion. After all, Cambrian fossil beds exhibit all major categories of multicellular organisms, even vertebrates! From an evolutionary point of view, the sudden appearance of such biodiversity without plenty of simpler antecedent life forms is a mystery.
Researchers from Nanjing Institute of Geology and Paleontology believe their spongy evidence now confirms from the fossil record that multicellular animals predated the Cambrian explosion by at least 60 million years. Ignoring the circular reasoning inherent in molecular clock extrapolations back into time, they see this sponge as support for evolutionary projections. From the evolutionary view, this discovery would also put sponges back in the lead as the “most primitive” animals, edging out comb jellies. Evolutionary scientists are eager to pin down the age and lineage of the little fossil because they believe it will help them determine not only when multicellular life evolved but also when our remote ancestors diverged from sponges.
Perhaps this more-or-less anatomically modern sponge should encourage evolutionary scientists to question their presuppositions. The existence of such a modern-looking sponge, like a muscle-flexing cnidarian, so deep in the fossil record suggests random evolutionary processes achieved remarkably modern results soon after life got going and then remained unbelievably stable across deep time. Of course, evolutionary presuppositions cannot permit such discoveries to rock the boat. When we look at this sponge through the lens of biblical history rather than evolutionary presuppositions, however, its modern form makes sense.
Once we discard unverifiable millions-of-years dates and evolutionary interpretations superimposed on the fossil record, we can understand the relationships of both fossil-rich Cambrian strata and this modern-looking Precambrian sponge to the historical global Flood about 4,350 years ago. The plethora of soft body parts preserved in many Cambrian fossil beds demands a history of rapid burial on a massive scale. The Cambrian “explosion” records sudden burial of countless organisms that likely lived in shallow seas adjacent to the pre-Flood supercontinent suddenly disrupted by the onset of the global Flood. The fossil-poor Precambrian sedimentary rock layers just beneath the Cambrian layers are best understood as the earliest deposited sediment layers of the Flood in deeper offshore waters where pre-Flood life was evidently scarce.
Answers in Genesis geologist Dr. Andrew Snelling explains, first of all, that the high phosphorus content of the Doushantuo sediment would have facilitated rapid fossilization:
This sponge is so small it could easily have been buried and fossilized. And the phosphatic matrix in which it has been fossilized in such exquisite detail has been shown in experiments to petrify and fossilize exceedingly rapidly, in some instances killing creatures while fossilizing them. Such speed explains the exquisite preservation of this tiny sponge. See “Soft Tissue Fossilization” for more details.
The Doushantuo Formation, composed of minerals only deposited in warm water, is sandwiched between fossiliferous Cambrian rock above and a rocky conglomerate below. Because this type of conglomerate typically results from underwater landslides and debris flows, Dr. Snelling explains, the Doushantuo Formation may help us picture the onset of the global Flood:
Immediately below the Doushantuo Formation strata are layers of broken rock pieces in a fine-grained matrix. Usually identified as diamictites, they are claimed by uniformitarians to be associated with glacial action and thought to document an ice age. However, that cannot be so. First, the Doushantuo Formation consists of many carbonate layers (limestones and dolomites) that could only have formed in warm waters. Second, these broken rock pieces in a fine-grained matrix—aka breccias—are known to form due to giant landslides and debris flows. Therefore, this conglomerate rock is not a diamictite but instead a breccia produced by landslides and debris flows in warm waters.
Indeed, the same pattern of strata is seen around the globe: Breccias overlain by carbonate-rich layers that could only be deposited in warm waters are in turn overlain by Cambrian fossiliferous sedimentary strata at a major erosional unconformity.8 In the western USA these breccias can be traced continuously from south to north for thousands of miles, and the warm water deposited carbonate strata lie above them and below the unconformity, between the uppermost Precambrian and Cambrian strata.
So what is the significance of this pattern within the biblical Creation-Flood framework? The fossiliferous Cambrian strata were deposited very early in the Flood, close to the time when the “fountains of the deep” were broken up. Some biblical geologists have proposed that the breccias below these Cambrian strata represent the collapse of the margins of the pre-Flood supercontinent. Earthquakes would have produced huge landslides and debris flows as the broken up margins cascaded onto the surrounding deep ocean floors. And water heated by molten rock rising to the earth’s surface in fissures encircling the globe would have facilitated the deposition of carbonate rock atop the breccias.
If this scenario is correct, then this tiny sponge fossil could be among the earliest creatures buried and fossilized during the Flood.
But what of the claim that this sponge was buried 600 million years ago? That claim is based on worldview-dependent assumptions. The sponge was found about five feet above a rock layer containing apatite fragments dated by radioisotopic lead-lead isochron dating to be 599.3 +/- 4.2 million years old. This “age” is an interpretation dependent on unverifiable assumptions that, Dr. Snelling explains, are not even reasonable:
For such isochron dating it has to be assumed there has been no contamination of the rocks since they formed. That is equivalent to saying there have been no movements of the radioactive parent uranium or daughter lead atoms into or out of the minerals and the rock for 600 million years! But uranium is highly soluble in water. These sedimentary layers were deposited in water, and groundwater has leached through these layers up until the present day. Therefore it makes no sense to assume there has been no contamination.9
Thus the Doushantuo sponge’s place in the fossil record is consistent with the very beginning of the global Flood, about 4,350 years ago. Anatomically it is a typical sponge. Nothing about it suggests it is the ancestor of anything except other sponges. It is neither an early evolutionary accomplishment nor a stepping-stone to more complex ones. It is just a sponge. A very nice little sponge, but a sponge nonetheless. And like all other kinds of animals, its ancestors were created by God about 6,000 years ago without evolution during the few 24-hour days of Creation Week.
Biologists have never observed any mechanism by which a single-celled organism can through natural processes acquire the genetic information to differentiate and organize its progeny into a multicellular organism.10 Neither has observational science revealed any way for multicellular organisms to acquire the genetic information to evolve into new, more complex kinds of organisms.
Evolutionary scientists are searching for a way to pinpoint when multicellular life evolved from single-celled life, whether those first multicellular animals were sponges or something else, and when those multicellular animals diverged and evolved into more complex forms. They are searching for things that—based on the biblical history of our origins provided by the Creator of the universe—never happened. God created all kinds of animals—and that would include sponges—without evolution during Creation Week about 6,000 years ago. He designed them to reproduce and to vary only within those created kinds. Thus it is no surprise to see that a sponge preserved in an uppermost Precambrian rock unit looks pretty much like sponges today. What scientists see in God’s world still affirms what we read in God’s Word.
about sponges and other “primitive” animals:
about the origin of multicellular life:
about other Precambrian microfossils and the Cambrian explosion:
about dating the fossil record:
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Explaining the significance of this report, PNAS summarizes it like this:
Phylogenomic extrapolations indicate the last common ancestor of sponges and eumetazoans existed deep in the Cryogenian, perhaps 200 million years (Myr) before the Cambrian (541 Ma). This inference implies a long Precambrian history of animals phylogenetically allied with sponges. However, there is yet little unequivocal paleontological evidence of Precambrian sponges. Here, we present a newly discovered 600-Myr- old fossil preserved at cellular resolution, displaying multiple poriferan features. The animal was covered with a dense layer of flattened cells resembling sponge pinacocytes, displaying a hollow tubular structure with apparent water inflow and outflow orifices. Although requiring additional specimens of similar form for confirmation, this finding is consistent with phylogenomic inference, and implies the presence of eumetazoan ancestors by 60 Myr before the Cambrian. (Yin et al., “Sponge Grade Body Fossil . . . ” doi:10.1073/pnas.1414577112)
The second crucial assumption is that the radioactive “clock” has always “ticked” at the same rate we measure today—that the rate at which two different uranium isotopes decay into lead atoms has never varied. Pb–Pb dating actually depends on knowing the decay rate of not just one, but two different sized uranium atoms that are radioactive, uranium-238 that decays into lead-206 and uranium-235 which decays into lead-207. Pb-Pb dating compares the lead-206 and lead-207 contents of the samples being dated.
Third, we must assume that the ratio of uranium-238 to uranium-235 atoms we measure today in host minerals has always been the same as when these minerals and rocks formed, presumably 600 million years ago! Of course, none of these assumptions can be supported, because no scientists have been around through the supposed 600 million years to check for contamination or to measure these decay rates and isotope ratios.
Some might point out that a zygote—a fertilized egg— differentiates and organizes its daughter cells into a complex multicellular organism. But a zygote already possesses the genetic information to do this. Zygotes obtain that information from parent organisms of their own kind.
God created microbes and multicellular organisms of all kinds to reproduce after their kinds during Creation Week about 6,000 years ago. We observe that organisms only vary within their own created kinds, as we infer from the Genesis creation account that they should. Nothing observable in biology bears up as evidence against His Word. He designed microbes to reproduce after their kinds, even exchanging genetic information horizontally, in order to equip them to propagate and fulfill their functions in this world. But He did not equip them to evolve into new multicellular life forms.
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