Reasons to Believe

Big Bacteria Help Resolve Big Creation/Evolution Debates

For most jobs the size of the applicant does not matter. But, there are exceptions: basketball centers must be tall, offensive tackles in professional football must be heavy, and World War II submarine sailors had to be both short and lean.

In biology size did not become a significant factor until the Cambrian explosion some 542 million years ago. At this event most of today’s main groups of animals, or animal phyla, suddenly appeared. Apparently, before the Cambrian explosion all that existed were cells or aggregates of cells. After the Cambrian explosion Earth is full of animals with appendages, specialized organs, and organized structures. In the same manner that the origin of life defies any reasonable naturalistic explanation,1 likewise the origin of animals is a stumper for naturalists.

Possible relief for naturalists appeared in a 1998 report that fossilized animal embryos had been found in the Doushantuo phosphorite rock deposit in the southern part of China dated to be 570 million years old.2 Now instead of having the origin of animals and virtually all animal phyla occurring within only 1-2 million years or less, those origins could be spread out over about 30 million years. The basis for concluding that the Doushantuo fossils were animals was that the cells were very large—held in tight groups of 2, 4, 8, 16, 32, and 64 cells that were reminiscent of embryonic cell division—and manifested nuclei.

Recently, a team of geologists and biologists from the University of Southern California and the University of Georgia made a strong case (here and here) against the identification of the Doushantuo fossils as animals.3They noted that there are no adult, juvenile, or infant fossils in the deposit, only the so-called embryos. While the cell sizes truly are enormous (just under a millimeter in diameter and, therefore, easily visible to the naked eye), such sizes are not without precedent among bacteria. The team pointed to a modern-day marine bacterium found off the coast of Namibia called Thiomargarita namibiensis that manifests virtually all of the properties of the Doushantuo fossils. They are the same size, tend to cluster in the same aggregates of 2 to 64 cells, and are just as densely vacuolated (same density of vacuoles in the cell). Moreover, when mats of T. namibiensis die, they leave a phosphorite deposit, and there is no other known modern-day process for laying down the kind of phosphorite deposits seen at Doushantuo.

The nuclei in the cells of the Doushantuo fossils remain a problem for a bacterial identification since all known bacterial fossils are devoid of nuclei. However, there is far from adequate resolution in the images of the Doushantuo fossils to unequivocally identify the “nuclei” as true nuclei. Also, two research teams have claimed that the observed presence of a textured capsule surrounding a few of the Doushantuo fossils shows that at least those fossils cannot be bacterial.4 However, the research team from the Universities of Southern California and Georgia has produced images showing that close bacterial analogues to T. namibiensis do indeed display similar textured capsules surrounding them.5

Considering the weight of evidence in favor of the bacterial identification, paleontologists must again acknowledge that only questionable evidence exists for the appearance of animals before the beginning of the Cambrian explosion. That being said, the sudden simultaneous appearance of virtually all animal phyla without any significant record of previously existing animals would defy any reasonable naturalistic explanation. In other words, the biblical creation model has scored another success.

The biblical creation model in a different context has scored one more success. As noted in a Today’s New Reason to Believe abstract (March 20, 2005), giant sulfur bacteria like T. namibiensis and the bacteria identified in the Doushantuo deposits are capable of thriving under both oxic (containing oxygen) and anoxic conditions. When conditions are oxic, the bacteria take up nitrate, taking advantage of their huge sizes to store enough nitrate to sustain their metabolic needs during long periods of anoxic conditions.6 Previous to the great oxygenation event that occurred just before the Cambrian explosion (see Connections 9, no. 2, 2007, 1-3) conditions on many parts of the earth oscillated between oxic and anoxic. Hence, conditions were ideal for the giant sulfur bacteria, which meant that the Creator could use these bacteria to prepare the way for the Cambrian explosion.

The creation of such a huge variety and population of animals at the Cambrian event would require an efficient cycling of phosphorus throughout the ecosystems. Evidently, the Creator engineered the amazing and unique designs and behaviors of giant sulfur bacteria to allow them to take advantage of the copious amounts of sulfide produced by the sulfate-reducing bacteria that were so predominant previous to the Cambrian event in order to sustain an aggressive phosphorous cycle at a rate ideal for the Cambrian animals. Such foresight, timing, planning, and engineering design testify of a supernatural, superintelligent Creator intent on ensuring that not only would the animals of the Cambrian explosion have all the resources and nutrients they would need, but also that these animals could be sustained on the earth for over a half billion years. In turn, a half billion-plus years of animal life upon the face of the earth provides human beings with all the resources and nutrients they need to launch and sustain global civilization.7

1 Fazale Rana and Hugh Ross, Origins of Life (Colorado Springs, CO: NavPress, 2004).
2 Shuhai Xiao, Yun Zhang, and Andrew H. Knoll, “Three-Dimensional Preservation of Algae and Animal Embryos in a Neoproterozoic Phosphorite” Nature 391 (1998): 553-58
3 Jake V. Bailey et al., “Evidence of Giant Sulfur Bacteria in Neoproterozoic Phosphorites,” Nature 445 (2007): 198-201; Philip C. J. Donoghue, “Embryonic Identity Crisis,” Nature 445 (2007): 155-56.
4 Leiming Yin, et al, “Doushantuo Embryons Preserved Inside Diapause Egg Cysts,” Nature 446 (2007): 661-663; Shuhai Xiao, Chaunming Zhou, and Xunlai Yuan, “Undressing and Redressing Ediacaran Embryos,” Nature 446 (2007): E9-E10.
5 Jake V. Bailey, et al, “Replying to Shuhai Xiao, Chaunming Zhou, and Xunlai Yuan,” Nature 446 (2007): E10.
6 Heide N. Schulz and Horst D. Schulz, “Large Sulfur Bacteria and the Formation of Phosphorite,” Science 307 (2005): 416-18.
7 Hugh Ross, Creation as Science (Colorado Springs, CO: NavPress, 2006): 128-47.

Subjects: Biodeposits, Geology and the Bible, Geophysical Design, Life Design, Speciation Events

Dr. Hugh Ross

Reasons to Believe emerged from my passion to research, develop, and proclaim the most powerful new reasons to believe in Christ as Creator, Lord, and Savior and to use those new reasons to reach people for Christ. Read more about Dr. Hugh Ross.