Fossils trapped in amber are not only beautiful, they may also preserve real ecological interactions, such as possible parasitism and symbiotic relationships between ants and mites, according to a new cutting-edge morphological study of six Baltic, Dominican and Burmese amber specimens.
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 represent possible interactions between different organisms that shape the environment,” said paleontologist Dr. Jose de la Fuente of the Game and Wildlife Research Institute.
“The identification and morphological characterization of fossil ants, including other insects in amber, provides a snapshot of life on Earth millions of years ago.”
In the new study, de la Fuente and colleagues analyzed four pieces of Cretaceous amber (99 million years ago), one Eocene amber (about 56 to 34 million years ago), and one Oligocene amber (about 34 to 23 million years ago).
The specimens included ancient ants, other organisms, and a rare phenomenon called syninclusion.
“The earliest ants, first discovered in the late Cretaceous period, were known as stem ants and left no modern descendants. All ants living today evolved from crown ants,” the paleontologists said.
“Both species are among the six ambers we studied and the hell ant, which evolved from the stem ant.”
The researchers examined the specimens using powerful microscopes, identifying the different species found inside and measuring the distances between the ants and other species.
In three of the six pieces of amber, ants were found in close proximity to the mites.
In the first photo, we found a crested ants, a wasp, and two ticks so close that they may have been traveling on the ants.
The second specimen contained stem ants and spiders, and the third contained hell ants, snails, millipedes, and several unidentified insects.
The fourth specimen contained a stem ant and a mite approximately 4 mm apart.
The fifth part included three different types of ants that are related to mites and some termites, as well as poorly preserved mosquitoes and winged insects.
In the sixth specimen, they found stem ants, along with wasps and spiders that are believed to be parasitic wasps. It looks like the ants are eating something.
It is resting against the inclusion of another insect, which could be a worm or larva, but there is no sign that the two were interacting, so scientists think this is a coincidence.
“The closest ant co-inclusions likely reflect behaviors and interactions between these organisms,” Dr. de la Fuente said.
“The ant-mite interaction proposed in the fourth specimen may reflect two possible scenarios.”
“First, there is a special symbiotic temporal relationship in which the tick attaches to the ant and free-rides its dispersal to a new habitat.”
“Second is parasitism, when the mites feed on the ant host during transport.”
Although amber fragments containing ants are rare, and amber fragments containing multiple species even rarer, some evidence has been published showing interactions between mites and ants, sometimes mutually beneficial.
Future studies may be able to clarify this by using micro-CT scans to look for attachment structures that allow the mites to climb onto ants for travel purposes.
“Future studies will need to use advanced imaging techniques to improve the analysis of interactions between different organisms in fossil amber inclusions,” said Dr. de la Fuente.
“Nonetheless, these results provide evidence of the insect’s behavioral and ecological habits.”
team’s paper Published in today’s diary Frontiers of 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. Ecole. Evol 14;doi: 10.3389/fevo.2026.1724595