Saturday, July 03, 2021





Scientists find unexplained collection of fossilized shark teeth in Jerusalem



Researchers found a collection of 80-million-year-old Squalicorax shark teeth from an Iron Age archaeological site in Jerusalem. Photo by Omri Lernau


July 3 (UPI) -- Scientists have uncovered a mysterious cache of shark teeth in the City of David in Jerusalem. The teeth were discovered at least 50 miles from where similar fossils might be unearthed by paleontologists.

Researchers detailed the discovery of the unexplained fossil collection this weekend at the Goldschmidt Geochemistry Conference.

The teeth were found buried in a material used to fill the basement of an Iron Age house for conversion into a larger dwelling.

"These fossils are not in their original setting, so they have been moved," lead researcher Thomas Tuetken said in a press release.

"They were probably valuable to someone; we just don't know why, or why similar items have been found in more than one place in Israel," said Tuetken, a geoscientist and paleontologist at the University of Mainz.

Scientists found ancient food waste, including fish bones, and pottery fragments near the shark teeth cache.

Researchers also recovered hundreds of bullae, clay seals used on confidential letters and packages. Those materials were determined to be 2,900 years old.

At first, the researchers assumed the shark teeth were contemporary with the other artifacts, but an archaeologist working on the excavation suggested the fossil teeth might belong to a Late Cretaceous shark.

Researchers analyzed the organic matter, elemental composition and crystallinity within the shark teeth and determined they were indeed ancient fossils, not Iron Age food scraps.

"Their strontium isotope composition indicates an age of about 80 million years," Tuetken said. "This confirmed that all 29 shark teeth found in the City of David were Late Cretaceous fossils -- contemporary with dinosaurs."

"More than that, they were not simply weathered out of the bedrock beneath the site, but were probably transported from afar, possibly from the Negev, at least [49.7 miles] away, where similar fossils are found," Tuetken said.

Since the discovery, separate archaeological excavations have yielded similarly displaced shark teeth caches in Maresha and Miqne.

"Our working hypothesis is that the teeth were brought together by collectors, but we don't have anything to confirm that," Tuetken said.

"There are no wear marks which might show that they were used as tools, and no drill holes to indicate that they may have been jewelry. We know that there is a market for shark's teeth even today, so it may be that there was an Iron Age trend for collecting such items," Tuetken said.

Paleontologists determined the shark teeth belonged to Squalicorax, or crow shark, an extinct genus of the mackerel shark family that lived during the Cretaceous period.

A paper describing the discovery was published in the journal Frontiers in Ecology and Evolution.

The City of David and the sharks' teeth mystery

GOLDSCHMIDT CONFERENCE

Research News

IMAGE

IMAGE: FOSSILISED SQUALICORAX TOOTH NR. #07815 FROM THE JERUSALEM SITE. view more 

CREDIT: OMRI LERNAU

Scientists have found an unexplained cache of fossilised shark teeth in an area where there should be none - in a 2900 year old site in the City of David in Jerusalem. This is at least 80 km from where these fossils would be expected to be found. There is no conclusive proof of why the cache was assembled, but it may be that the 80 million-year-old teeth were part of a collection, dating from just after the death of King Solomon*. The same team has now unearthed similar unexplained finds in other parts of ancient Judea.

Presenting the work at the Goldschmidt Conference, lead researcher, Dr. Thomas Tuetken (University of Mainz, Institute of Geosciences) said:

"These fossils are not in their original setting, so they have been moved. They were probably valuable to someone; we just don't know why, or why similar items have been found in more than one place in Israel".

The teeth were found buried in material used to fill in a basement before conversion to a large Iron-Age house. The house itself was situated in the City of David, one of the oldest parts of Jerusalem, found nowadays in the largely Palestinian village of Silwan. They were found together with fish bones thrown away as food waste 2900 years ago, and other infill material such as pottery. Intriguingly, they were found together with hundreds of bullae - items used to seal confidential letters and packages - implying a possible connection with the administrative or governing class at some point. Normally archaeological material is dated according to the circumstances where it is found, and so at first it was assumed that the teeth were contemporary with the rest of the find. Dr. Tuetken said:

"We had at first assumed that the shark teeth were remains of the food dumped nearly 3000 years ago, but when we submitted a paper for publication, one of the reviewers pointed out that the one of the teeth could only have come from a Late Cretaceous shark that had been extinct for at least 66 million years. That sent us back to the samples, where measuring organic matter, elemental composition, and the crystallinity of the teeth confirmed that indeed all shark teeth were fossils. Their strontium isotope composition indicates an age of about 80 million years. This confirmed that all 29 shark teeth found in the City of David were Late Cretaceous fossils - contemporary with dinosaurs. More than that, they were not simply weathered out of the bedrock beneath the site, but were probably transported from afar, possibly from the Negev, at least 80 km away, where similar fossils are found".

Since the first finds, the team have found other shark teeth fossils elsewhere in Israel, at the Maresha and Miqne sites. These teeth are also likely to have been unearthed and moved from their original sites.

Dr. Tuetken said:

"Our working hypothesis is that the teeth were brought together by collectors, but we don't have anything to confirm that. There are no wear marks which might show that they were used as tools, and no drill holes to indicate that they may have been jewellery. We know that there is a market for shark's teeth even today, so it may be that there was an Iron Age trend for collecting such items. This was a period of riches in the Judean Court. However, it's too easy to put 2 and 2 together to make 5. We'll probably never really be sure".

The shark teeth which have been identified come from several species, including from the extinct Late Cretaceous group Squalicorax. Squalicorax, which grew to between 2 and 5 metres long, lived only during the Late Cretaceous period (which was the same period as the late dinosaurs), so acts as a reference point in dating these fossils.

Commenting, Dr. Brooke Crowley (University of Cincinnati) said:

"This research by Dr. Tuetken and colleagues is an excellent example of why it is so important to approach a research question with as few assumptions as possible, and how sometimes we have to revisit our initial assumptions. It also highlights how beneficial it can be to apply multiple tools to answer a research question. In this case, the authors used both strontium and oxygen isotopes, as well as x-ray diffraction and trace element analysis to establish most likely age and origin of the fossil teeth. It was a monumental of work but these efforts have revealed a much more interesting story about the people who lived in this region in the past. I am very excited by this work and hope that one day, we might be able to unravel the mystery of why these fossil teeth are being recovered from cultural deposits".


CAPTION

Artist's impression of a Squalicorax shark

CREDIT

Dimitri Bogdanov

Dr. Crowley was not involved in this work. The work relating to the Jerusalem finds has been published in the peer-reviewed journal Frontiers in Ecology and Evolution 8:570032 (https://doi.org/10.3389/fevo.2020.570032), Dr. Crowley edited this paper for the journal. This press release contains additional material not mentioned in the publication.

Notes

This work is presented on 6th July, but is being released to the press early.

*The find dates from the time of the immediate descendants of King Solomon; Rehoboam, Abija, Assa, and Jehoshapat.

The Goldschmidt Conference is the World's main geochemistry conference. It is hosted alternately by the European Association of Geochemistry (Europe) and the Geochemical Society (USA). The 2021 conference (virtual) takes place from 4-9 July, https://2021.goldschmidt.info/. The 2022 conference takes place in Hawaii.













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