Who are the early ancestors of scorpions, spiders, and horseshoe crabs? This long-standing mystery in paleontology has been solved thanks to the discovery of a significant fossil by a doctoral student at the Faculty of Geosciences and Environment of the University of Lausanne (UNIL), with support from a CNRS scientist. This fossil links modern species to those from the Cambrian period, approximately 505 million years ago.
Modern scorpions, spiders, and horseshoe crabs belong to a vast family of arthropods that first appeared on Earth around 540 million years ago. More specifically, they are part of a subgroup known as chelicerates, which are characterized by their pincer-like appendages used for feeding, dragging prey, or injecting venom. Identifying the ancient ancestors of this specific group has been a significant challenge for paleontologists.
Since the early days of fossil study, the question of which primitive arthropods could be considered direct ancestors to modern chelicerates has intrigued scientists. The challenge was compounded by a lack of fossils from the crucial period between 505 and 430 million years ago, a gap that left significant gaps in the evolutionary timeline.
Lorenzo Lustri, during his doctoral studies at UNIL, provided the missing piece of this puzzle. By examining a hundred fossils from the Fezouata site in Morocco, which date back to 478 million years ago, Lustri identified a fossil that bridges the gap between Cambrian organisms and modern species. This groundbreaking study was published in Nature Communications.
The Fezouata site, discovered in the early 2000s, has been the subject of numerous studies. The fossil described in the publication, one of the most abundant in the site, had not been previously detailed. Measuring between 5 to 10 millimeters, it was named Setapedites abundantis. This small but significant animal provides the first complete lineage of chelicerates, connecting the first arthropods to modern horseshoe crabs, spiders, and scorpions.
We initially planned just to describe and name this fossil. We never imagined it would hold so many secrets, says Lorenzo Lustri, the lead author of the study who defended his doctoral thesis in March 2023. It was an exciting surprise to realize, after meticulous observations and analyses, that it filled an important gap in the tree of life.
Despite this breakthrough, the fossil still holds more secrets. Its anatomical features offer further insights into the early evolution of chelicerates and may even link this group to other debated fossil forms. Additionally, a temporary exhibition about the Fezouata biota, in collaboration with UNIL, will soon be held at the Palais de Rumine in Lausanne, showcasing this significant discovery.
This discovery not only illuminates the evolutionary history of chelicerates but also highlights the importance of fossil studies in understanding the complexity of life’s history on Earth. The research conducted by Lustri and his colleagues has opened new avenues for exploring the early diversity and evolutionary pathways of ancient arthropods, providing a clearer picture of how modern species have evolved over millions of years.
Sources
CNRS | Lustri, L., Gueriau, P. & Daley, A.C. Lower Ordovician synziphosurine reveals early euchelicerate diversity and evolution. Nat Commun 15, 3808 (2024). doi.org/10.1038/s41467–024–48013-w
- Share this article:
Discover more from LBV Magazine English Edition
Subscribe to get the latest posts sent to your email.
The Satire of the Trades, the text used for centuries by children in Ancient Egypt to learn to read
For centuries, children in Ancient Egypt learned to read using a text known as The Satire of the Trades, a document dating back to around 2400 BCE. This educational text…
Qian Xuesen, the Scientist Expelled from the United States Who Brought China Into the Space Race
On October 31, 2009, an elderly man, nearly a century old, passed away in Beijing. His name was Qian Xuesen, and in China, he is considered a national hero for…
Two Wines Dominated the Market in Late Antiquity in the Mediterranean: Gaza and Cilician
A recent study has brought to light interesting details about the distribution and consumption patterns of two of the most important wines in the eastern Mediterranean during Late Antiquity. These…
Farnese Atlas, the First Known Representation of the Celestial Sphere
Atlas was one of the Titans in Greek mythology, son of Iapetus and the Oceanid Clymene, and brother of Prometheus. After the war against the Olympian gods, Zeus condemned him…
Orsippus of Megara, the First Athlete to Compete Naked in the Olympic Games
A quick glance at any artwork from Ancient Greece gives an idea of the almost religious importance of nudity, and if we interpret the images literally, how widespread its practice…
Sandby Borg, the Place where Archaeologists Found a Chilling Iron Age Scene Frozen in Time
The isolated island of Öland, off the southeastern coast of Sweden, holds within its windswept landscape the eroded remains of several fornborgs, circular stone fortifications built during the Iron Age.…
Spectacular Celtic Burial Chamber from the 6th Century BC Discovered in the Center of a 65-Meter-Diameter Burial Mound in Germany
In a remarkable archaeological discovery in the Danube Plain, near Riedlingen, Baden-Württemberg (Germany), an early Celtic burial chamber has come to light. This find is located at the center of…
Reliefs with Figures of Guardians, Celestial Ancestors, and Mythical Animals of the Kaanu’l Mayan Dynasty Found in Mexico
The recent archaeological discovery in the Dzibanché Archaeological Zone, Quintana Roo (Mexico), has provided new insights into the grandeur of the Kaanu’l dynasty, one of the most influential in the…
Lucone di Polpenazze, the Bronze Age pile-dwelling settlement that was preserved because a fire caused it to collapse into the lake
Located in the Lombardy region, near the impressive Lake Garda, the archaeological site of Lucone di Polpenazze is a living testament to Prehistory in northern Italy. This place, a large…
Sacred tunic of Alexander the Great identified in one of the Macedonian tombs at Vergina in Greece
A recent discovery in Tomb II at Vergina, Macedonia, Greece, has revealed what appears to be the sacred “chiton” or tunic of Alexander the Great, a finding that could change…
A House from 8,000 Years Ago Found in Serbia Belonged to the First Sedentary Farmers of Europe
Did the first agricultural societies in Europe live nomadically, or were they (seasonally) sedentary? How did sedentarism spread between Anatolia and Europe, and how did the first sedentary people influence…
New findings during the extraction of a Phoenician shipwreck in Spain, the most complete ancient vessel found in the Mediterranean Sea
The much-anticipated start of the extraction of the Phoenician shipwreck located in Mazarrón, Murcia, named Mazarrón 2—currently the most complete ancient ship found in the Mediterranean—has begun with a series…
Something went wrong. Please refresh the page and/or try again.
