“Ants cut back on how much they invest per worker in one of the most dietarily costly tissues to benefit the colony,” Matte explains. “They’re reallocating resources from individual maintenance toward a shared labor force.”
Strength of the collective
The team proposes that the pattern seen in ants mirrors a broader tendency in the evolution of social complexity. The shift from solitary existence to integrated societies parallels the move from single-celled life to multicellular organisms.
When an organism is a single cell, that cell must perform every role required for life. In contrast, cells in a multicellular animal frequently simplify and specialize, depending on the group for defense and nourishment.
“It’s a recurring theme in the evolution of multicellularity: cooperating units can be individually less complex than a lone cell, but together achieve much greater capabilities,” Matte says. Whether reducing individual investment to improve the group makes evolutionary sense outside of ants remains uncertain, and it likely involves reproductive dynamics more than simple nutritional trade-offs.
Disposable workers
This work examined ant species that already separate reproduction from labor, where workers do not breed. That reproductive division appears to be the crucial condition enabling a strategy of inexpensive workers. The researchers argue this explains why similar evolutionary shifts haven’t been detected, at least so far, in more complex social mammals like wolves—or in humans with their intricate societies. Both wolves and people retain strong individual reproductive interests. Ant workers can be rendered expendable because they do not transmit their own genes; they function as extensions of the queen’s reproductive role.
Before searching for ant-like solutions to trade-offs between quality and quantity in other taxa, the group plans more detailed studies of ants. Economo, Matte, and collaborators intend to broaden their work to other ant tissues, including nervous and muscular systems, to determine if the reduction in individual investment reaches beyond the exoskeleton. They are also examining ant genomes to identify genetic changes that enabled the shift from investing in fewer, higher-quality individuals to producing many cheaper workers. “We still need a lot of work to understand ants’ evolution,” Matte says.
Science Advances. 2025. DOI: 10.1126/sciadv.adx8068
