Researchers believe they have discovered fossils of the earliest insects covered in pollen from around 280 million years back in Russia. The remains of these ancient earwig-like insects, known as tillyardembiids, were found in a lagoon. These extinct tillyardembiids had pollen preserved on their heads, thoraces, legs, and abdomens, a researcher, Dr. Alexander Khramov, said.
Paleontologists in Russia discovered fossil remains of ancient earwig-like insects, known as tillyardembiids, in a lagoon near the village of Chekarda, about 1,600km from Moscow. These tillyardembiids, which hail from the Paleozoic era from around 542 to 250 million years ago, were found covered in pollen from seed-producing, non-flowering plants known as gymnosperms. This was long before flowering plants became more common, sometime between 100 to 50 million years ago. The scientists said their findings, published in the journal Biology Letters, predate the earliest known pollen-covered insects by 120 million years.
They also believe the behavior of these tillyardembiids could be seen as a precursor to insect pollination. Dr. Alexander Khramov, a senior researcher at the Paleontological Institute, Russian Academy of Science in Moscow, said: “Our discovery sheds light on the early evolution of insect pollination. “It provides direct, smoking-gun evidence of pollen dispersion by Paleozoic insects.” Dr. Khramov and his colleagues found a handful of extinct tillyardembiids with pollen preserved on their heads, thoraces, legs, and abdomens.
Recently, Khramov and his colleagues scrutinized 425 fossils of Tillyardembia in the institute’s collection. Six had clumps of pollen grains trapped on their heads, legs, thoraxes, or abdomens, the team reports on February 28 in Biology Letters. A proportion that small isn’t surprising, Khramov says, because the fossils were preserved in what started out as fine-grained sediments. The early stages of fossilization in such material would tend to wash away pollen from the insects’ remains.
The pollen-laden insects had only a couple of types of pollen trapped on them, the team found, suggesting that the critters were very selective in the tree species they visited. “That sort of specialization is in line with potential pollinators,” says Michael Engel, a paleoentomologist at the University of Kansas in Lawrence who was not involved in the study. “There’s probably vast amounts of such specialization that occurred even before Tillyardembia, we just don’t have evidence of it yet.”
Further study of these fossils might reveal if Tillyardembia had evolved special pollen-trapping hairs or other such structures on their bodies or heads, says Conrad Labandeira, a paleoecologist at the National Museum of Natural History in Washington, D.C., also not part of the study. It would also be interesting, he says, to see if something about the pollen helped it stick to the insects. If the pollen grains had structures that enabled them to clump more readily, for example, then those same features may have helped them grab Velcro-like onto any hairlike structures on the insects’ bodies.
Source: Science News