Marching ants in amber. Photo by Christine Sosiak
A 35-million-year-old Baltic amber hides the world’s oldest marching ant. This finding suggests that marching ants once existed in Europe.
Marching ants prefer to live in groups, usually numbering in the millions per colony. They prefer to migrate, do not have a fixed dwelling, and when they encounter obstacles such as puddles, they can connect their bodies together and build a bridge for large forces to pass.
However, this type of marching ant is mostly found in Africa and South America and has never been found in Europe.
The first marching ant fossils were found in amber 16 million years ago in the Dominican Republic, and this discovery is the second confirmed marching ant fossil. This discovery is the first proof that marching ants once existed in Europe. The paper was published Nov. 23 in Biology Letters.
It is worth mentioning that the amber hiding the marching ant was preserved in the Harvard Museum of Comparative Zoology for nearly a hundred years, until researchers such as Christine Sosiak of the New Jersey Institute of Technology discovered the secret.
“There are hundreds of drawers filled with fossilized insects in the museum, and while collecting data from the project, I happened to find small specimens labeled with common ant types.” “When I put this specimen under the microscope, I immediately realized that the label was not accurate — this is by no means a common ant species,” Sosiak said. ”
Sosiak and his colleagues then created a well-preserved 3D model of the ant based on high-resolution CT scan analysis. They found that, unlike most common ants, the insect has no eyes, only a sharp jaw, waist segment and large glands that secrete the protective fluids needed to live underground.
This means that the ants in amber are closer to the eyeless marching ants currently found in Africa and South Asia. They may use trace pheromones to hunt in groups and build short-lived underground nests to live underground pastoral life.
“It may have just gotten lost,” Sosiak speculated, suggesting that the marching ant may have lost its track pheromones, veered off course, and got stuck in the resin.
The researchers named the fossil Dissimulodorylus perseus, meaning the hidden Perseus, the Greek mythological hero Perseus, who used his limited vision to defeat the snake demon Medusa.
Study author Phillip Barden, an assistant professor of biology at the New Jersey Institute of Technology, believes that Europe was hotter and wetter than today when fossils formed, possibly providing an ideal habitat for ancient marching ants. However, Europe has undergone several cooling cycles over tens of millions of years, to the point that it may not be suitable for tropical species.
For now, the fossil will continue to be preserved at the Harvard Museum of Comparative Zoology for future study. (Source: Meng Lingxiao, China Science News)
Related paper information:https://doi.org/10.1098/rsbl.2022.0398