Paleontologists unearthed unique fossilized insects, afflicted by parasitic fungi, in amber approximately 99 million years old from northern Myanmar. Within the clear resin, fungal shoots clearly emerge from the insects’ heads and bodies—direct proof that fungi of the genus Ophiocordyceps had already developed the capacity to infect, kill, and utilize insects for spore dispersal during the Cretaceous period.
Two Hosts—Two Infection Scenarios
Parasites as a Factor in the Ancient Ecosystem
This is one of the oldest known demonstrations of so-called “zombie behavior” in fungi: by infiltrating the host’s body, they seize control of its conduct, and then form fruiting bodies protruding outside to cast off spores and infect new victims.
The investigation was conducted by a team headed by paleontologist Yuhui Zhuang from Yunnan University. The findings are detailed in the journal Proceedings of the Royal Society B. Scientists described two novel species of prehistoric parasitic fungi based on the amber specimens.
Two Hosts—Two Infection Scenarios
One amber piece contained a fly, the other an ant. In the fly, the fungus Paleoophiocordyceps ironomyiae sprouted from the head, while in the ant, the fungus Paleoophiocordyceps gerontoformicae emerged from the thorax. In both instances, the preserved fungal fruiting bodies were in superb condition due to the amber’s natural preserving qualities. This allowed paleontologists to document the instant the fungus had already gained mastery over the insect’s body but had not yet finished the tissue decomposition process.
Conrad Labandeira from the Smithsonian National Museum of Natural History, who was not involved in the study, remarked that the discoveries confirm that fungal parasitism in arthropods is an ancient strategy, strikingly similar to the conduct of contemporary fungi that infect ants in tropical forests.
Parasites as a Factor in the Ancient Ecosystem
The presence of such well-preserved parasitic structures is important for understanding ancient ecology and species evolution:
— fungal parasitism was already widespread around 100 million years ago and might have exerted considerable influence on insect populations;
— such finds reveal intricate interplays between microorganisms and macroscopic animals in prehistoric ecosystems;
— the morphology of the fungi and their infection mechanism offer clues to the origin of present-day forms of parasitism.
The researchers speculate that the insect infestation occurred immediately prior to them being encased in the sticky resin—the precursor to amber. This explains why the fungal shoots are so well preserved, allowing observation of the very moment of biological “takeover.”
These revelations broaden the scope of paleobiology and demonstrate how deeply rooted in life’s history are mechanisms once thought to be contemporary—such as the manipulation of victim behavior by parasites.
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