30,000-Year-Old Fossil Feathers of Griffon Vulture Found in Italy

Fossil feathers are usually preserved as carbonaceous films and impressions in lacustrine and marine sediments, or embedded in amber, but rarely mineralized. In a new study, paleontologists examined mineralized plumage of a 30,000-year-old griffon vulture preserved in ash-rich volcanic sediments of the Colli Albani volcanic complex, Rome, Italy. The bird’s feathers were preserved in three dimensions, with preservation of tissue ultrastructures such as melanosomes. These ultrastructures are mineralized in nanocrystalline zeolite, a mode of preservation not previously reported in fossil soft tissues.

The fossil vulture was found in 1889 near Rome by a local landowner who recognized its remarkable preservation.

The entire body was preserved as a three-dimensional impression, with fine details such as the eye lids and wing feathers.

Led by University College Cork paleontologist Valentina Rossi, the new research shows that preservation of feathers extends to tiny microscopic feather pigment structures.

“Fossil feathers are usually preserved in ancient mudrocks laid down in lakes or lagoons,” Dr. Rossi said.

“The fossil vulture is preserved in ash deposits, which is extremely unusual.”

“When analyzing the fossil vulture plumage, we found ourselves in uncharted territory.”

“These feathers are nothing like what we usually see in other fossils.”

By analyzing tiny samples of the fossil feathers using electron microscopes and chemical tests, the authors found that the feathers are preserved in the mineral zeolite, a mode of fossil preservation never reported before.

“Zeolites are minerals rich in silicon and aluminum and are common in volcanic and hydrothermal geological settings,” Dr. Rossi said.

“Zeolites can form as primary minerals (with pretty crystals) or can form secondarily, during the natural alteration of volcanic glass and ash, giving the rock a mudrock-like aspect.”

“The alteration of the ash due to passage of water induced the precipitation of zeolites nanocrystals that, in turn replicated the feathers to the tiniest cellular detail.”

“The fine preservation of the feather structures indicates that the vulture carcass was entombed in a low temperature pyroclastic deposit.”

“We are used to think that volcanic deposits are associated with hot, fast-moving pyroclastic currents that will destroy soft tissues,” said University of Milan’s Professor Dawid Iurino.

“However, these geological settings are complex and can include low temperature deposits that can preserve soft tissues at the cellular level.”

“The fossil record is continually surprising us, be it new fossil species, strange new body shapes, or in this case, new styles of fossil preservation,” said University College Cork’s Professor Maria McNamara.

“We never expected to find delicate tissues such as feathers preserved in a volcanic rock.”

“Discoveries such as these broaden the range of potential rock types where we can find fossils, even those preserving fragile soft tissues.”

A paper on the findings was published in the journal Geology.

_____

Valentina Rossi et al. Fossil feathers from the Colli Albani volcanic complex (Late Pleistocene, Central Italy) preserved in zeolites. Geology, published online March 18, 2025; doi: 10.1130/G52971.1