Giant predatory worms roamed the seafloor until 5.3 million years ago

February 18, 2021

An international study in which the University of Granada participated--recently published in the journal Scientific Reports--has identified a new fossil record of these mysterious animals in the northeast of Taiwan (China), in marine sediments from the Miocene Age (between 23 and 5.3 million years ago)

These organisms, similar to today's Bobbit worm (Eunice aphroditois), were approximately 2 m long and 3 cm in diameter and lived in burrows

An international study in which the University of Granada (UGR) participated (recently published in the prestigious journal Scientific Reports) has revealed that the seafloor was inhabited by giant predatory worms during the Miocene Age (23-5.3 million years ago).

The scientists identified a new fossil record (indirect remains of animal activity such as, for instance, dinosaur tracks, fossilised droppings, insect nests, or burrows) linked to these mysterious animals, which are possible predecessors of today's Bobbit worm (Eunice aphroditois). Based on the reconstruction of giant burrows observed in Miocene-age marine sediments from northeast Taiwan (China), the researchers concluded that these trace fossils may have colonised the seafloor of the Eurasian continent about 20 million years ago.

Olmo Míguez Salas of the UGR's Department of Stratigraphy and Palaeontology (Ichnology and Palaeoenvironment Research Group) participated in the study, which was conducted as part of a project funded by the Taiwanese Ministry of Science and Technology (MOST, 2018) of which the researcher was a beneficiary.

Míguez Salas and the other researchers reconstructed this new fossil record, which they have named Pennichnus formosae. It consists of an L-shaped burrow, approximately 2 m long and 2-3 cm in diameter, indicating the size and shape of the organism-- Eunice aphroditois--that made the structure.

Bobbit worms hide in long, narrow burrows in the seafloor and propel themselves upward to grab prey with their strong jaws. The authors suggest that the motion involved in capturing their prey and retreating into their burrow to digest it caused various alterations to the structure of the burrows. These alterations are conserved in the Pennichnus formosae and are indicative of the deformation of the sediment surrounding the upper part of the burrow. Detailed analysis revealed a high concentration of iron in this upper section, which may, the researchers believe, indicate that the worms continuously rebuilt the opening to the burrow by secreting a type of mucus to strengthen the wall, because bacteria that feed on this mucus create environments rich in iron.

Although marine invertebrates have existed since the early Paleozoic, their bodies primarily comprise soft tissue and are therefore rarely preserved. The fossil record discovered in this study is believed to be the earliest known specimen of a subsurface-dwelling ambush predator.

Olmo Míguez Salas notes that this finding "provides a rare view of the behaviour of these creatures under the seafloor and also highlights the value of studying fossil records to understand the behaviour of organisms from the past."
-end-


University of Granada

Related Fossil Record Articles from Brightsurf:

How to fix the movement for fossil fuel divestment
Bankers and environmentalists alike are increasingly calling for capital markets to play a bigger role in the war on carbon.

New fossil ape is discovered in India
A 13-million-year-old fossil unearthed in northern India comes from a newly discovered ape, the earliest known ancestor of the modern-day gibbon.

Fossil pollen record suggests vulnerability to mass extinction ahead
Reduced resilience of plant biomes in North America could be setting the stage for the kind of mass extinctions not seen since the retreat of glaciers and arrival of humans about 13,000 years ago, cautions a new study published August 20 in the journal Global Change Biology.

Australian fossil reveals new plant species
Fresh examination of an Australian fossil -- believed to be among the earliest plants on Earth -- has revealed evidence of a new plant species that existed in Australia more than 359 Million years ago.

Tracking fossil fuel emissions with carbon-14
Researchers from NOAA and the University of Colorado have devised a breakthrough method for estimating national emissions of carbon dioxide from fossil fuels using ambient air samples and a well-known isotope of carbon that scientists have relied on for decades to date archaeological sites.

Fossil record analysis hints at evolutionary origins of insects' structural colors
Researchers from Yale-NUS College in Singapore and University College Cork have analyzed preserved scales from wing cases of two fossil weevils from the Late Pleistocene era to better understand the origin of light-scattering nanostructures present in present-day insects.

Reconstructing the diet of fossil vertebrates
Paleodietary studies of the fossil record are impeded by a lack of reliable and unequivocal tracers.

Fossil is the oldest-known scorpion
Scientists studying fossils collected 35 years ago have identified them as the oldest-known scorpion species, a prehistoric animal from about 437 million years ago.

Canadian tundra formerly covered in rich forest: Ancient plant fossil record shows
Canada's northernmost islands, Ellesmere and Axel Heiberg islands in Nunavut, were home to a vibrant, temperate forest 56 million years ago, according to fossil research just published by University of Saskatchewan (USask) scientists.

New Colorado fossil record documents life's rebound after Cretaceous-Paleogene extinction
Nearly 66 million years ago, the reign of dinosaurs ended and the ascendency of mammals on Earth began.

Read More: Fossil Record News and Fossil Record Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.