The Cambrian was a funny time. California was just a twinkle in Mother Nature’s eye, and Nevada was little more than a soggy plain of ocean-goo. The same could be said for much of Utah. Instead of jagged mountains and determined pioneers, Utah was covered in a warm, shallow ocean and indifferent sponges. Professional people say that Utah was at or near the equator during this time as the super-continent Pangaea slapped itself together. How these professional people know this, I can’t say. Perhaps they found a fossilized spring break tee-shirt, or a greasy old DVD of sponges gone wild. Utah marked the western shoreline of Pangaea for a time, before finally sinking below the waves some 525 million years ago as the seas advanced eastwards.
Now, things started out simple enough. Sponges were the tough-guys of the land, spending the majority of their time shoplifting from the locals and then leaning on them for “protection money”. For millions of years the lesser advanced blobs of sea-goo were at the whim of the sponges. These were dark times indeed. Then, without warning, a new tough-guy showed up….
Trilobites. The three-lobed arthropod of fury. These little guys could skeletonize a cow in less than a minute, and even the sponges were helpless to do anything other than soak up to their weight in water. At first, there was just one type of Trilobite, a friendly little guy named the Olenellid trilobite. These guys seemed to be content to be themselves for millions of years until, very suddenly, they became 17,000 different types, all with equally fascinating names, such as Bolaspidella Contracta, Asaphiscus Kingi, and Thomas.
The great thing about Utah is that a large number of these little guys lived in here when the oceans were at the right depth and temperature. You head out to the stimulating city of Delta Utah and the drive a few miles more and there you are, right in the middle of the parched desert that was once a trilobite-ridden ocean.
Sadly, as is the case for us all, Trilobites were doomed the minute they showed up on the scene. Utah continued to sink deeper and deeper below the ocean, like a Twinkie soaking in a pool of milk. Soon the oceans became too deep for our friends the Trilobites, and they disappeared from Utah. This was just the beginning of their troubles. Pangea was giving up the ghost and was becoming several different countries, like France, Ireland and probably others. Some believe that this is somehow connected to a drop in earthy temperatures which not only killed the trilobites, but 98% of all other life on earth. Oddly enough, it is the sponge that comes through like a champ, having been forced to live a life of quiet spongy dignity while the trilobites were off snorting coke and ignoring youth liquor laws. Makes you think.
So yes, 220 million years ago the Trilobites disappeared forever. Some think that the entire planet became encased in ice, not unlike the Planet Hoth. Others believe that sharks, which had recently shown up, simply ate everything else. A comet impact site known as Hudson Bay is also conveniently dated at about the same time as when the Trilobites made their last gasp. I suspect that the comet was carrying sharks, which arrived on earth at the behest of the sponges, who according to my personal research hated the trilobites. All we have now are cold, occasionally creepy rock-based trilobites who no longer feel pain, and await the opportunity to exact their revenge on the sponges.