Ants Make Individuals Weaker to Build Bigger Societies

Biology is full of tradeoffs, and one of the most familiar is whether success comes from quality or quantity — from building stronger individuals or producing more of them.

A study published in Science Advances shows how that tradeoff has played out in ants. By comparing hundreds of species, researchers found that ants with especially large colonies tend to build workers with thinner exoskeletons, investing less in individual protection to support far more workers overall. The findings suggest that as societies grow more complex, evolutionary pressure can shift away from individual durability and toward systems that succeed through numbers and coordination.

“There’s this question in biology of what happens to individuals as societies they are in get more complex. For example, the individuals may themselves become simpler because tasks that a solitary organism would need to complete can be handled by a collective,” said senior author Evan Economo, in a press release.

How Ant Colonies Trade Strength for Numbers

Ant colonies range from a few dozen individuals to societies with millions of workers. As colonies grow, jobs that would overwhelm a solitary insect — foraging, nest defense, and limiting disease — can be distributed across many bodies.

To see how that shift might reshape individuals, the researchers focused on the cuticle, the hardened outer layer of the exoskeleton. It helps protect ants from predators, dehydration, and infection, and supports movement — but it is also nutritionally costly to build, drawing on nitrogen and minerals that can be scarce.

Measuring the Cost of Ant Protection

Using high-resolution 3D X-ray scans, the team measured cuticle and body volumes across more than 500 ant species. Cuticle investment varied, in some species it made up only 6 percent of total body volume; in others, up to 35 percent.

When the researchers mapped those measurements against colony size and evolutionary history, they found that species investing less in cuticle tended to support much larger colonies. Rather than maximizing protection worker by worker, these ants appear to rely more on collective strategies to buffer weaker individual armor.

“Ants reduce per-worker investment in one of the most nutritionally expensive tissues for the good of the collective,” said the study’s lead author, Arthur Matte. “They’re shifting from self-investment toward a distributed workforce, resulting in more complex societies. It’s a pattern that echoes the evolution of multicellularity, where cooperative units can be individually simpler than a solitary cell, yet collectively capable of far greater complexity.”

Read More: Bumblebees and Ants Battle in Violent Nectar Wars, Leading to Death and Food Shortage

When Numbers Beat Strength

Thinner armor sounds risky, but in a large colony the risk is spread out. Losses are absorbable, dangerous tasks can be shared, and defense can emerge from coordination rather than toughness.

That colony-level resilience may help explain another pattern: ants with lower per-worker investment also tended to show higher diversification rates — meaning they split into new species more frequently over evolutionary time. One hypothesis is that colonies with lower nutritional demands can expand into nutrient-limited habitats, opening new ecological opportunities that speed diversification.

What Ant Colonies Reveal About Tradeoffs Everywhere

The pattern the researchers uncovered isn’t limited to insects. Similar quality-versus-quantity tradeoffs show up in human history, from military organization to everyday decisions — cases where scale and coordination can matter as much as individual strength.

“The tradeoff between quantity and quality is all around. It’s in the food you eat, the books you read, the offspring you want to raise,” Matte said. “It was fascinating to retrace how ants handled it through their long evolution. We could see lineages taking different directions, being shaped by different constraints and environments, and ultimately giving rise to the extraordinary diversity we observe today.”

Read More: Our Ancestors Used to Make Yogurt Using Live Ants — And the Recipe Still Works

Article Sources

Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:

• This article references information from the recent study published in Science Advances: The evolution of cheaper workers facilitated larger societies and accelerated diversification in ants