Scientists studied ants and plants to identify them in a 60-million-year history. Plants provided food for ants and helped spread their seeds, influencing how plants interact with other organisms during climate and biodiversity emergencies.
Scientists have combined fossils, DNA, and data on the habitat preferences of modern species to explore how ants and plants have evolved over the previous 60 million years.
Matthew Nelsen, a research scientist at the Field Museum in Chicago, describes ants living underground and in the canopy of trees.
Matthew Nelsen's photo shows a leaf cutter ant, one of the more than 14,000 species that are alive today.
Nelsen and his colleagues investigated how ants and flowering plants, or angiosperms, originated 140 million years ago and spread to new environments.
Nelsen and his co-authors (Corrie Moreau at Cornell University, Kevin Boyce at Stanford University, and Richard Ree at the Field Museum) compared the climates that 1,400 modern ant species inhabit, including data on temperature and precipitation. This information was coupled with a time-scaled reconstruction of the ant family tree, based on genetic information and ant fossils preserved in amber. Many ant behaviors, like where they build their nests and what habitats they inhabit, appear to be deeply
One of the most essential ant-plant interactions is the ability to eat from a plant's extrafloral nectary. Credit: Matthew Nelsen
According to Nelsen, ants inhabited most of the forest 60 million years ago and built their nests underground. (They also evolved to draw water vapor out of small holes in their leaves, too; frogs, snakes, and epiphytic plants also moved to the trees around this time.)
Some flowering plants that inhabited these arid areas began to spread outward, eventually adapting to more drought-tolerant environments. Some of the ants may have followed the plants, since they provided food for them, according to Nelsen.
In light of the climate and biodiversity challenges we're facing, the researchers think it's important to demonstrate how plants played a role in ant evolution and proliferation.
"This research demonstrates the significant role that plants play in forming ecosystems," says Nelsen. "Shifts in plant communities, such as those we are seeing as a result of historic and modern climate change, can cascade and affect animals and other organisms relying on these plants."
Matthew P Nelsen, Corrie S Moreau, C Kevin Boyce, and Richard H Ree, in Evolution Letters, 31 March 2023. DOI: 10.1093/evlett/qrad008
