Polish Scientists Make Extraordinary Discovery in Turkey: A 44-Million-Year-Old Iguana Fossil Defies Scientific Consensus

An international team including paleontologists from the Polish Academy of Sciences has uncovered a 44-million-year-old iguana fossil in Anatolia, providing the first evidence of these reptiles in the ancient Balkanatolia region.

The Lost Archipelago: The Exotic World of Balkanatolia

For most of the Paleocene and Eocene epochs—from 66 to 34 million years ago—the region of modern-day Anatolia and the Balkan Peninsula formed an isolated archipelago of large and small islands, resembling modern Indonesia. This exotic land, named Balkanatolia, was previously known exclusively for its peculiar and diverse island mammal fauna, including unique forms of primates, bats, marsupials, and other specific species. The contemporary reptile fauna of this area had remained entirely unknown until now, according to Dr. Hab. Georgios Georgalis from the Institute of Systematics and Evolution of Animals of the Polish Academy of Sciences (PAN).

Now, as part of new research, scientists from Poland, Germany, the USA, Turkey, and France have described the first lizard from Balkanatolia in an article published in the journal Scientific Reports.

A Surprising Visitor from Europe: Ocean Crossing on Tree Trunks After a Tsunami

To great surprise, the specimen belonged to iguanas—a group that currently has a rather extensive range but does not inhabit the broader area of Anatolia. Iguanas are also not currently found in Europe, but fossil records clearly indicate they were present on the continent during the Eocene. Consequently, the new iguana find from Balkanatolia is interpreted as the result of “seaborne dispersal” from Europe, likely facilitated by the animals drifting on tree trunks following a tsunami, explained the paleobiologist and first author of the publication.

Unique Dentition as the Key to Fossil Identification

The recovered fossil material is quite fragmentary, which precludes a more precise species identification and analysis of the animal’s external morphology. Nevertheless, iguana teeth are characterized by specific dentition, featuring three distinct cusps on the crown. Therefore, even this small fragment of the fossil clearly indicates the presence of an iguana in Balkanatolia for the first time.

The Puzzle of Paleobiogeography and the Search for More Complete Remains

Georgalis added that this feature is extremely rare and almost completely absent in other iguanas. He noted that it occurs only in certain extinct and modern groups of iguanas from France and the Americas, indicating that the paleobiogeography of this group in the Eocene was far more enigmatic than previously thought. The researcher expressed confidence that ongoing fieldwork in the region will yield more complete skeletal remains of the Anatolian iguana, allowing for more precise anatomical and taxonomic interpretations.

Extraordinary Migratory Capabilities of Iguanas Confirmed by Science

Furthermore, this same migration scenario—animals drifting on tree trunks—is currently used to explain the modern geographical distribution of iguanas on remote Pacific Ocean islands and the Caribbean Sea. The new discovery from Turkey provides further evidence of iguanas’ extraordinary ability to successfully migrate across oceans and colonize distant lands and oceanic islands throughout their evolutionary history, Georgalis concluded. The research was conducted as part of a grant funded by the National Science Centre (NCN).