Lichens, which are complex symbiotic associations between fungi and algae (or cyanobacteria), fulfill vital ecological functions and inhabit a wide array of surfaces, including petrified remains. Emerging scientific investigations indicate that these organisms can serve as bio-indicators for locating fossils in western North America and are amenable to detection via remote sensing technologies.
Preferential colonization of dinosaur bones by lichens. Image credit: Pickles et al., doi: 10.1016/j.cub.2025.09.036.
“This groundbreaking research underscores how contemporary life forms can assist in the discovery of ancient ones,” commented Dr. Brian Pickles, a researcher affiliated with the University of Reading.
“It is truly astonishing to contemplate that these lichens, essentially self-contained miniature biomes, are established on the fossilized remnants of dinosaurs that perished more than 75 million years ago.”
“The deployment of drone technology for the identification of lichen spectral signatures holds the potential to fundamentally transform the methodologies employed by paleontologists in their search for fossils.”
In the course of their investigation, Dr. Pickles and his associates observed that two particular lichen species—namely, Rusavskia elegans and Xanthomendoza trachyphylla—were found to colonize as much as 50% of exposed fossilized bones, while colonizing less than 1% of the surrounding geological fragments.
This phenomenon is likely attributable to the fact that dinosaur bones offer the alkaline, calcareous, and porous environmental conditions that these specific lichens find most conducive.
“This discernible pattern of lichen growth, favoring fossilized bone, has been acknowledged for many years, but it has only recently been subjected to quantitative analysis,” stated Dr. Caleb Brown, a researcher at the Royal Tyrrell Museum of Palaeontology.
“Upon initial discovery of dense concentrations of exposed fossil bone, such as in bonebeds, it is frequently the vibrant ‘expanse’ of orange lichen that captures attention first, rather than the bones themselves.”
Employing drones equipped with sophisticated sensors, the research team successfully identified lichen-adorned fossils from aerial imagery captured at a resolution of 2.5 cm per pixel.
The lichens exhibit distinct spectroscopic characteristics, manifesting as reduced reflectivity in the blue light spectrum and amplified reflectivity in the infrared spectrum.
This innovative methodology presents considerable advantages for paleontological exploration, particularly in remote and challenging terrains where conventional ground-based surveys are difficult to implement.
The adoption of this approach could significantly expedite the pace of fossil discovery, concurrently diminishing operational expenses and minimizing environmental disturbance.
This current research builds upon a foundation of anecdotal observations that have been documented by paleontologists over several decades.
As far back as 1980, paleontologist Darren H. Tanke hypothesized that the characteristic orange hue of lichens found on Centrosaurus bones might indeed be detectable by orbital satellites—a prediction that appears to be closer to realization now that such occurrences can be identified through advanced airborne drone technology.
“This investigation utilizing drones establishes a crucial precedent for the mapping of substantially larger geographical areas through the deployment of aircraft and satellites,” remarked Dr. Derek Peddle, a researcher associated with the University of Lethbridge.
“The novel lichen indicators we have developed are poised to enhance our capacity to Llocate fossils across extensive and varied landscapes.”
“It is immensely gratifying to integrate our advanced imaging capabilities with the specialized knowledge of this international team to propel dinosaur discovery forward through the remote sensing of lichen populations.”
The collaborative publication detailing their findings was released this week in the esteemed scientific journal Current Biology.
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Brian J. Pickles et al. 2025. Remote sensing of lichens with drones for detecting dinosaur bones. Current Biology 35 (21): R1044-R1045; doi: 10.1016/j.cub.2025.09.036
