An international team of researchers have described a remarkable new species of fish that lived in the sea in the time of the dinosaurs in the late Jurassic about 150 million years ago.

The new species of bony fish had teeth like a piranha, which the researchers from the ARC Centre of Excellence for Coral Reef Studies (Coral CoE, Australia) and Jura-Museum Eichstätt (Germany), suggest they used as piranhas do: to bite off chunks of flesh from other fish.

As further support for that notion, the team also found the victims – other fish that had apparently been nibbled on – in the same limestone deposits in South Germany (the quarry of Ettling in the Solnhofen region) where this piranha-like fish was found.

“We have other fish from the same locality with chunks missing from their fins,” said Prof David Bellwood of Coral CoE at James Cook University.

“This is an amazing parallel with modern piranhas which feed predominantly not on flesh but the fins of other fishes. It’s a remarkably smart move as fins regrow, a neat renewable resource. Feed on a fish and it is dead; nibble its fins and you have food for the future.”

The newly described fish is part of the world famous collections in the Jura-Museum in Eichstätt. It comes from the same limestone deposits that contained the first feathered proto-bird known as Archaeopteryx.

Careful study of the fossilized specimen’s well preserved jaws revealed long, pointed teeth on the exterior of the vomer, a bone forming the roof of the mouth, and at the front of both upper and lower jaws. Additionally, there are triangular teeth with serrated cutting edges on the pre-articular bones that lie along the side of the lower jaw.

The tooth pattern and shape, jaw morphology and mechanics suggest a mouth equipped to slice flesh or fins, the international team of researchers report. The evidence points to the possibility that the early piranha-like fish may have exploited aggressive mimicry in a striking parallel to the feeding patterns of modern piranha.

“We were stunned that this fish had piranha-like teeth,” Dr Martina Kölbl-Ebert of Jura-Museum Eichstätt (JME-SNSB) said.

“It comes from a group of fishes (the pycnodontids) that are famous for their crushing teeth. It is like finding a sheep with a snarl like a wolf. But what was even more remarkable is that it was from the Jurassic.”

“Fish as we know them, bony fishes, just did not bite flesh of other fishes at that time. Sharks have been able to bite out chunks of flesh, but throughout history bony fishes have either fed on invertebrates or largely swallowed their prey whole. Biting chunks of flesh or fins was something that came much later,” Kölbl-Ebert explained

Or, so it had seemed.

“The new finding represents the earliest record of a bony fish that bit bits off other fishes, and what’s more, it was doing it in the sea,” Bellwood said, noting that today’s piranhas all live in freshwater.

“So when dinosaurs were walking the earth and small dinosaurs were trying to fly with the pterosaurs, fish were swimming around their feet tearing the fins or flesh off each other.”

The researchers call the new find a “staggering example of evolutionary versatility and opportunism.” With one of the world’s best known and studied fossil deposits continuing to throw up such surprises, they intend to keep up the search for even more fascinating finds.

Citation: Kölbl-Ebert, M, Ebert, M, Bellwood, DR & Schulbert, C (2018) A Piranha-like Pycnodontiform Fish from the Late Jurassic. Current Biology 278(21): 3516 – 3521 DOI: 10.1016/j.cub.2018.09.013

Author Contact:

Prof David Bellwood (AUSTRALIA) – on leave until Nov.
david.bellwood@jcu.edu.au

Dr Martina Kölbl-Ebert (GERMANY)
Koelbl-Ebert@jura-museum.de

For More Information:

Catherine Naum, Communications Manager
ARC CoE for Coral Reef Studies
catherine.naum1@jcu.edu.au
P: +61 (0) 7 4781 6067 (AEST, +10 UTC)
M: +61 (0) 428 785 895

An international team of scientists has used the 23-million-year fossil record to calculate which marine animals and ecosystems are most at risk of extinction today.

In a paper published in the journal Science, the researchers found those animals and ecosystems most threatened are predominantly in the tropics.

“Marine species are under threat from human impact, but knowledge of their vulnerabilities is limited,” says study co-author, Professor John Pandolfi from the ARC Centre of Excellence for Coral Reef Studies at the University of Queensland.

The researchers found that the predictors of extinction vulnerability, geographic range size and the type of organism, have remained consistent over the past 23 million years.

As such, they were able to use fossil records to assess the baseline extinction risk for marine animals, including sharks, whales and dolphins, as well as small sedentary organisms such as snails, clams and corals.

They then mapped the regions where those species with a high intrinsic risk are most affected today by human impact and climate change.

“Our goal was to diagnose which species are vulnerable in the modern world, using the past as a guide” says study lead author, Assistant Professor Seth Finnegan from the University of California Berkeley.

“We used these estimates to map natural extinction risk in modern oceans, and compare it with recent human pressures on the ocean such as fishing, and climate change to identify the areas most at risk,” says Professor Pandolfi.

“These regions are disproportionately in the tropics, raising the possibility that these ecosystems may be particularly vulnerable to future extinctions.”

The scientists say that identifying the regions and species at greatest risk means conservation efforts can be better targeted.

“We believe the past can inform the way we plan our conservation efforts. However there is a lot more work that needs to be done to understand the causes underlying these patterns and their policy implications,” says Asst. Professor, Seth Finnegan

Co-author, Dr Sean Anderson from Simon Fraser University, British Columbia adds, “It’s very difficult to detect extinctions in the modern oceans but fossils can help fill in the gaps.”

“Our findings can help prioritize areas and species that might be at greater risk of extinction and that might require extra attention, conservation or management – protecting vulnerable species in vulnerable places.”

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Paper

The paper, Paleontological baselines for evaluating extinction risk in the modern oceans by Seth Finnegan, Sean C. Anderson, Paul G. Harnik, Carl Simpson, Derek P. Tittensor, Jarrett E. Byrnes, Zoe V. Finkel, David R. Lindberg,Lee Hsiang Liow, Rowan Lockwood, Heike K. Lotze, Craig M. McClain, Jenny L. McGuire, Aaron O’Dea, & John M. Pandolfi., is published in the journal Science

Copies of the paper can be accessed at: http://www.eurekalert.org/jrnls/sci/

 Contacts

John Pandolfi, j.pandolfi@uq.edu.au, +61 (0) 400 982 301

Seth Finnegan, sethf@berkeley.edu, +1 (951) 452-2759

Sean Anderson, sean_anderson@sfu.ca

Paul Harnik, paul.harnik@fandm.edu, +1 (717) 358-5946

Eleanor Gregory, (Communications), eleanor.gregory@jcu.edu.au, +61 (0) 428 785 895