Jurassic Fossil Reveals Violent Squid Attack in Progress
An international team of paleontologists from the University of Plymouth, the University of Kansas and the Forge Fossils has found a specimen of the squid-like cephalopod Clarkeiteuthis montefiorei preserved with the herring-like fish Dorsetichthys bechei in its two arms; the bones in the head of the fish are broken in a manner that suggests a quite violent attack.
The 195-million-year-old specimen was found in the 19th century near Lyme Regis on the Jurassic coast of southern England.
The fossil predates previously recorded similar specimens by more than 10 million years.
“Since the 19th century, the Blue Lias and Charmouth Mudstone formations of the Dorset coast have provided large numbers of important body fossils that inform our knowledge of coleoid paleontology,” said lead author Professor Malcolm Hart, a paleontologist in the School of Geography, Earth & Environmental Sciences at the University of Plymouth.
“In many of these mudstones, specimens of paleobiological significance have been found, especially those with the arms and hooks with which the living animals caught their prey.”
“This, however, is a most unusual if not extraordinary fossil as predation events are only very occasionally found in the geological record.”
“It points to a particularly violent attack which ultimately appears to have caused the death, and subsequent preservation, of both animals.”
The fossilized remains indicate a brutal incident in which the head bones of the fish were apparently crushed by its attacker.
The researchers have two hypotheses for how the two animals ultimately came to be preserved together for eternity.
“Firstly, the fish was too large for its attacker or became stuck in its jaws so that the pair settled to the seafloor where they were preserved,” they said.
“Alternatively, Clarkeiteuthis montefiorei took its prey to the seafloor in a display of ‘distraction sinking’ to avoid the possibility of being attacked by another predator. However, in doing so it entered waters low in oxygen and suffocated.”
Malcolm Hart et al. Life and Death in the Jurassic Seas of Dorset, Southern England. EGU 2020, abstract # 1466; doi: 10.5194/egusphere-egu2020-1466