Life-SavingWorms?
Figure 1 ModernBristle Worm Foraging in the Ocean (credit YouTube)
We love our superheroes, don’t we – Superman, Wonder Woman, Batman, Spider-Man – to name a few. Each seems to possess some sort of unique super-human powers while on mission to save humanity from bad guys or evil aliens. How about “Superworm”? Did you ever in your wildest imagination think that worms might have played a key role in sparing life on planet earth? Let’s take a look; you might be surprised!
As a geology student in the late 1960s, I studied numerous rock specimens that looked like Figure2. My professor told me they were fossil tracks from worms that once burrowed in the muds of ocean floors over 500 million years ago during the Cambrian Era.The oldest worm-like fossil ever discovered is dated at 555 million years,found in Australia. But what these worms looked like had to be left to our imaginations. The problem, of course, was that worms are slimy creatures composed mostly of soft parts; animals with hard skeletons, like trilobites,make much better-preserved fossils. That began to change when in 1909 Charles Walcott discovered 508-million-year-old exceptionally well -preserved fossils in the Burgess Shale of British Columbia. But it wasn’tuntil highly sophisticated photographic techniques, such as backscatter SEM and elemental mapping were perfected in the 21st century, that scientists were able to observe soft-bodied fossils of organisms such as worms. Figure 3 is an example of a fossilized bristle worm in the Burgess Shale using backscatter SEM; next to it is an artist’s rendition of what the worm might have looked like. Notice how similar it looks to the modern version of bristle worm in Figure 1.
Figure 2 Fossil Worm Burrows – Arthrophycus (credit Pixels)
In my book, “Countdown to Adam”, I dedicate a small storyline to worms. During what is known as the “Cambrian Explosion”, a time when most animal phyla appeared on earth for the first time, 14 ocean-dwelling worm phyla also emerged. Interestingly, the same 14 worm phyla have persisted through geologic time to the present, without any new phyla being added. In the novel, Tyros, one of the fictitious angels, is conducting a tour through the fictional, heavenly Museum of Remembrance. His group has just waded into the muds of an ancient Cambrian Sea; let’s join the adventure.
“Tyros reached down and scooped some large handfuls of mud and dumped it into a clear bucket; the mud seemed to be alive with movement, all kinds of squiggly things. He deposited the mud into a sieve, and then ran water through the sieve until all the mud-creatures, mostly worms, were cleaned up and in plain view. ‘Just for fun, lets see how many different phyla of worms you can identify. Why don’t we make it like an “I spy” game?’ Those assembled were quick to respond.”
“I spy a bristle-headed worm – I spy a segmented worm – I spy an arrow-shaped worm – I spy a worm shaped like a goblet – I spy a worm with an over-sized jaw – I spy a worm that looks like an acorn – I spy a thread-like round worm – I spy a ribbonworm – I spy a clawed velvet worm – I spy a horse-hair worm – I spy a horseshoe worm – I spy a flat worm – I spy a peanut worm – I spy a ciliated flat worm.”
“Most exceptional, said Tyros, You guys are good; indeed, you have identified all fourteen phyla of mud-dwelling worms in this bucket. I think you each would have made great scientists had you chosen that profession.”
Figure 3 508-million-year-old Fossil Bristle Worm (creditPinterest)
Over billions of years of earth history, the planet has experienced incredible swings in climate and environment, many of which nearly extinguished the possibility of life as we know it. Toxic, acidic oceans. Earth totally covered in glacier ice. Atmosphere devoid of oxygen. Super-hot atmosphere filled with greenhouse gases carbon dioxide and methane. Heavy meteor bombardments. Runaway volcanic eruptions. Lethal cosmic and solar radiation. The worst climate catastrophe, the Great Oxygen Extinction, occurred about 2.3 billion years ago; 99.9 percent of all life was wiped out for over 300 million years! These are but a few of the life-threatening scenarios. Was it not for interventions by our Creator, planet earth would likely have gone the way of every other known planet in our solar system as well as exoplanets orbiting nearby stars – zero chance for even the most primitive life-forms to take hold? But here we are today with highly advanced life bustling all around us; it’s nothing short of a miracle. It appears that God foreknew the threats and intervened at just the right times to make our planet habitable; this is consistent with the creation narrative found in Genesis. God can use any means to accomplish his outcomes; in this story we see how he used lowly worms to act as a thermostat to help regulate earth’s climate so certain bacteria wouldn’t totally dominate and squeeze out other life forms that the Creator wanted to bring forth.
Cyanobacteria are a type of blue-green algae (bacteria) that generate oxygen as a byproduct of “oxygenic photosynthesis”. To fuel their growth engine (metabolism), cyanobacteria take into their cell food-packets that consist of 6 molecules of carbon dioxide plus 12 molecules of water plus sunlight; once inside the cell, the food-packet is then converted into an energy-packet consisting of one molecule of sugar (glucose) plus 6 molecules of oxygen plus 6 molecules of water. The chemical formula is: 6CO2 + 12H2O + light energy =equals= C6H12O6 (glucose) + 6O2 + 6H2O. During the photosynthesis process, these bacteria break down and utilize, as an electron donor, the hydrogen from a water molecule (H2O); the remaining oxygen (from that water) is then released back into the ocean and atmosphere.
Figure 4 Blue-Green Algae (credit The Horse)
When it comes to the earth’s climate, blue-green algae can act as a blessing or acurse. As colonies of algae increase, they remove (breathe) CO2 from the atmosphere which helps to cool down the earth, but if they remove too much CO2, the earth loses its protective greenhouse gas shield and can become a ball of glacial ice, threatening life (as in the Great Oxygen Extinction). On the other hand, algae (exhale) copious amounts of oxygen into the air as a waste product. Earth’s current oxygen level is 21 percent, a perfect amount to support life. But too much algal growth has pushed prehistoric oxygen levels to over 30 percent; when this happened, a single lightning strike would have created catastrophic fires, torching the primordial land vegetation, threatening life.
I can just imagine our triune God discussing this potential threat to the advancement of life and coming up with a host of solutions, among which are worms that dwell in ocean sediments. Scientists have discovered a potential model of that plan; the key is the chemical phosphate (PO4). Cyanobacteria and plants need phosphate for photosynthesis to work; they derive phosphate from the seawater. Less available phosphate means lower growth rates, and in turn, reduced CO2 intake from the air, and less oxygen pumped back into seawater and air. Ocean sediments contain many types of bacteria that don’t thrive around oxygen. When worms burrow into these sediments, they churn up the bacteria, exposing them to oxygen in the phosphate-rich seawater. As this happens, these bacteria compensate by removing phosphate from the water and storing it inside their cells.
Worms depend on oxygen. So, a reduction in cyanobacteria means less oxygen pumped into seawater. Less available oxygen reduces the worm population; fewer digging worms exposes less mud-dwelling bacteria to oxygen, so they don’t sequester as much phosphate. This then makes more phosphate available to cyanobacteria and a resulting growth spurt. Thus, the humble worm played a key role 508 million-years-ago regulating the temperature of earth and providing a stable climate for life to advance and thrive.
As a side note, evolution appears to have had little to do with the advancement of bristleworms through the ages. In a previous blog, I wrote about how all modern eye-types, in a multitude of complex designs, appeared simultaneously in the Cambrian Era. Similarly, the modern bristle worm in Figure 1 looks nearly identical to its 508-million-year-old bristle worm ancestor in Figure 3. Again, it seems that our Creator got the bristle worm body-type right the first time, not needing to rely on evolution. If God can use a worm to preserve life on our planet, might he have a plan to keep our present climate suitable for humanity? Let’s give God a little more credit!
