Fossils preserved in amber are not only exquisite but also provide insights into ancient ecological interactions, including potential parasitism and symbiotic relationships between ants and mites. This revelation comes from a groundbreaking morphological study analyzing six amber specimens: Baltic, Dominican, and Burmese.
Fossils of an ant colony preserved in Baltic Sea amber from Lithuania. Image credit: José de la Fuente & Agustín Estrada-Peña, doi: 10.3389/fevo.2026.1724595.
“Inclusions in amber reveal potential interactions between various organisms that shaped prehistoric environments,” stated paleontologist Dr. Jose de la Fuente from the Game and Wildlife Research Institute.
“The identification and morphological analysis of fossil ants and other insects in amber offer a glimpse into life on Earth millions of years ago.”
In this pioneering study, de la Fuente and colleagues examined four pieces of Cretaceous amber (dating back 99 million years), one Eocene amber (approximately 56 to 34 million years ago), and one Oligocene amber (roughly 34 to 23 million years ago).
The specimens comprised ancient ants and other organisms, as well as a rare phenomenon known as syninclusion.
“The earliest ants, identified from the late Cretaceous period, were known as stem ants, which left no modern descendants. All existing ants evolved from crown ants,” the researchers emphasized.
“Both ant types are present in the six amber specimens we investigated, including the hell ant, which evolved from stem ants.”
The researchers utilized advanced microscopy to identify various species and document the distances between ants and other organisms in the specimens.
In three of the six amber pieces, ants were discovered in close proximity to mites.
The first specimen revealed crested ants, a wasp, and two ticks closely associated, suggesting they may have been traveling on the ants.
The second piece showcased stem ants alongside spiders, while the third contained hell ants, snails, millipedes, and numerous unidentified insects.
The fourth specimen featured a stem ant and a mite approximately 4 mm apart.
The fifth amber fragment included three distinct types of ants related to mites and termites, as well as poorly preserved mosquitoes and winged insects.
In the sixth sample, stem ants were found alongside wasps and spiders believed to be parasitic. It appeared the ants were consuming something, resting against another insect inclusion that might be a worm or larva, yet no interaction was evident, hinting it could be a coincidence.
“The closest co-inclusions of ants likely reflect behaviors and interactions between these organisms,” Dr. de la Fuente noted.
“The ant-mite interaction observed in the fourth specimen may indicate two potential scenarios.”
“First, a special symbiotic relationship where the tick hitches a ride on the ant to disperse to new habitats; second, parasitism occurring when the mites feed on the ant host during transport.”
While amber fragments featuring ants are scarce, those with multiple species are even rarer. Existing evidence suggests interactions between ants and mites may sometimes be mutually beneficial.
Future studies could clarify these interactions using micro-CT scans to explore attachment structures that may facilitate the mites’ travel on ants.
“Advanced imaging techniques are essential for enhancing the analysis of interactions among diverse organisms in fossil amber inclusions,” concluded Dr. de la Fuente.
For more details, read the research team’s paper published today in Frontiers in Ecology and Evolution.
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Jose de la Fuente and Agustín Estrada-Peña. 2026. Description of fossil amber containing ant co-inclusions. Front. Ecol. Evol 14; doi: 10.3389/fevo.2026.1724595.
Source: www.sci.news
