A University of Kansas paleontologist has discovered a long-extinct sea
worm during excavations in the "Spence Shale Lagerstätte," a fossilized
fossil treasure trove. Currently, the discovery has been made public in the
journal Historical Biology.
In the High Creek region of the Spence Shale, a geological formation
spanning northern Utah and southern Idaho, Rhiannon LaVine, a research
associate with the KU Biodiversity Institute and Natural History Museum, was
doing fieldwork when she discovered the fossil. Since the early 1900s, the
region has gained notoriety for being home to more than 90 different species
of Cambrian trilobites and soft-bodied fossils.
LaVine recalled, "I split open one of these pieces of rock one of the last
times we were out there and I instantly knew it was something that wasn't
typical." "These radial blades that resemble stars or flowers are what we
initially notice. I immediately showed it to Julian Kimmig (the principal
author). He was confused. The man has stated, "I've never seen anything like
that." Paul Jamison, a local who has worked the site for years, was with us
when we went exploring. If there is anything within that someone has seen,
he has seen it. However, he had missed it.
LaVine spoke with colleagues about the enigmatic fossil after bringing it
back to the KU Biodiversity Institute, where it is currently a part of the
permanent paleontological collection.
I was displaying it to everyone and requesting their opinions. said LaVine.
"Nobody had a thought. We speculated that it may be a wiwaxia, a fairly
unusual species from around that period, but the Spence region doesn't have
many examples of it. It might also be a scale worm, albeit no authentic
scale worms from that era are known. Perhaps it was a young jellyfish,
although given its sharp edges and straight lines, it would be strange. So I
was unable to receive a reliable response.
The fossil was then subjected to scanning electron microscopy and
energy-dispersive X-ray spectroscopy by LaVine and associates from the
University of Missouri.
The KU researcher explained, "We mainly wanted to make sure that this was a
biological thing because it's possible it could have just been some weird
mineral growth." So, the main reason we gave it to them was for that. It is
somewhat shorter than the length of a smartphone at around 7 or 8 cm. For
that kind of fossil, it's rather large. We were able to undertake the
scanning to rule out the possibility that it was merely a mineral
growth.
Finally, LaVine and her co-authors were able to identify the fossil as
belonging to a hitherto undiscovered species of annelid, a varied phylum
that contains around 21,000 species of "segmented worm" that may be found in
terrestrial, freshwater, and marine settings all over the world.
Shaihuludia shurikeni is the scientific name given to the species by
LaVine, who also co-authored the study revealing the new fossil worm. Frank
Herbert's "Dune" novels give the worms on the planet Arrakis the native name
Shai-Hulud, while the Japanese term "shuriken" (literally, "throwing star")
refers to the form of the blade-like chaetae (the stiff bristles that
distinguish many annelids).
LaVine stated, "I've participated in describing species before, but this is
the first one I've named. "Actually, I was able to identify its genus, so I
guess I can add that to my resume. Because I'm a big ol' nerd and at the
time I was getting extremely psyched about the "Dune" movies, it was the
first thing that sprang to mind.
Shaihuludia shurikeni is a huge deal, much like the fictional worm of the
same name. It's not every day that a new species of Cambrian annelid is
described.
Lead author Julien Kimmig is a paleontologist from the State Museum of
Natural History in Karlsruhe, Germany. "Annelids are very rare in the
Cambrian of North America, and so far we only knew of a single specimen from
the Spence Shale," he said.
"The newly discovered annelid Shaihuludia shurikeni is particularly
fascinating since it is distinct from other Cambrian annelids in that it
possessed some really spectacular chaetae. Because much of the soft tissue
is preserved as an iron oxide "blob," which suggests the animal died and was
degrading for some time before it was fossilized, the method the fossil is
preserved is also very interesting. However, we demonstrate in the research
that even with poor preservation, fossils may still be identified.
Burgessochaeta were unexpectedly reclassified as a result of the team's
reexamination of a fossilized annelid that had previously been discovered in
the Spence Shale. Burgessochaeta had previously only been discovered in a
renowned fossil deposit in British Columbia, Canada.
Burgessochaeta is mostly found in the Burgess Shale, according to LaVine.
Canadia, which is sort of a wastebasket genus for many of the annelids that
emerge out of these types of deposits, was the name of a similar worm that
was once discovered in our Spence Shale decades ago.
"For a very long time, no one really looked into it, but when we acquired
this one, we looked at the other annelid located there a bit more closely.
Perhaps this was a different version of it or somehow connected to it,
LaVine speculated. This is the first time the second annelid from the Spence
Shale has been described outside of the Burgess Shale, and we found it to be
closer to Burgessochaeta.
Both worm species would have lived in an invertebrate-dominated marine
habitat that included trilobites, brachiopods, mollusks, and early
arthropods. The abundant marine fauna of the mid-Cambrian is renowned.
This revelation makes us consider the depths of time, according to LaVine.
"Every animal we are familiar with is present when we glance outside. Now we
may stroll by a duck, visit a beach, and observe all the sea life that lives
there. We anticipate things somewhat. However, after that, we may use a
little of our imagination to speculate about what might have happened a
million years ago, or in this case, more than 500 million years ago. How
does the ocean seem in such case?
"You're going to see a lot of the same guys, but evolution has made them a
little bit alien. It's fascinating to consider that the same piece of land
upon which we now stand has witnessed a variety of historical events and
environmental conditions over the course of billions of years. Aliens'
worlds have existed under our feet.
Provided by
University of Kansas
