Ants – with their wise farming practices and efficient navigation techniques – could inspire solutions for some human problems

Photo by Kumar Kranti Prasad

By Scott Solomon, The Conversation

King Solomon may have gained some of his famed wisdom from an unlikely source – ants.

According to a Jewish legend, Solomon conversed with a clever ant queen that confronted his pride, making quite an impression on the Israelite king. In the biblical book of Proverbs (6:6-8), Solomon shares this advice with his son: “Look to the ant, thou sluggard, consider her ways and be wise. Which having no guide, overseer, or ruler, provideth her meat in the summer, and gathereth her food in the harvest.”

While I can’t claim any familial connection to King Solomon, despite sharing his name, I’ve long admired the wisdom of ants and have spent over 20 years studying their ecology, evolution and behaviors. While the notion that ants may offer lessons for humans has certainly been around for a while, there may be new wisdom to gain from what scientists have learned about their biology.

Ants have evolved highly complex social organizations.

Lessons from ant agriculture

As a researcher, I’m especially intrigued by fungus-growing ants, a group of 248 species that cultivate fungi as their main source of food. They include 79 species of leafcutter ants, which grow their fungal gardens with freshly cut leaves they carry into their enormous underground nests. I’ve excavated hundreds of leafcutter ant nests from Texas to Argentina as part of the scientific effort to understand how these ants coevolved with their fungal crops.

Much like human farmers, each species of fungus-growing ant is very particular about the type of crops they cultivate. Most varieties descend from a type of fungus that the ancestors of fungus-growing ants began growing some 55 million to 65 million years ago. Some of these fungi became domesticated and are now unable to survive on their own without their insect farmers, much like some human crops such as maize.

Ants started farming tens of millions of years before humans.

Ant farmers face many of the same challenges human farmers do, including the threat of pests. A parasite called Escovopsis can devastate ant gardens, causing the ants to starve. Likewise in human agriculture, pest outbreaks have contributed to disasters like the Irish Potato Famine, the 1970 corn blight and the current threat to bananas.

Since the 1950s, human agriculture has become industrialized and relies on monoculture, or growing large amounts of the same variety of crop in a single place. Yet monoculture makes crops more vulnerable to pests because it is easier to destroy an entire field of genetically identical plants than a more diverse one.

Industrial agriculture has looked to chemical pesticides as a partial solution, turning agricultural pest management into a billion-dollar industry. The trouble with this approach is that pests can evolve new ways to get around pesticides faster than researchers can develop more effective chemicals. It’s an arms race – and the pests have the upper hand.

Ants also grow their crops in monoculture and at a similar scale – after all, a leafcutter ant nest can be home to 5 million ants, all of which feed on the fungi in their underground gardens. They, too, use a pesticide to control Escovopsis and other pests.

Yet, their approach to pesticide use differs from humans’ in one important way. Ant pesticides are produced by bacteria they allow to grow in their nests, and in some cases even on their bodies. Keeping bacteria as a living culture allows the microbes to adapt in real time to evolutionary changes in the pests. In the arms race between pests and farmers, farming ants have discovered that live bacteria can serve as pharmaceutical factories that can keep up with ever-changing pests.

Whereas recent developments in agricultural pest management have focused on genetically engineering crop plants to produce their own pesticides, the lesson from 55 million years of ant agriculture is to leverage living microorganisms to make useful products. Researchers are currently experimenting with applying live bacteria to crop plants to determine if they are effective at producing pesticides that can evolve in real time along with pests.

Improving transportation

Ants can also offer practical lessons in the realm of transportation.

Ants are notoriously good at quickly locating food, whether it’s a dead insect on a forest floor or some crumbs in your kitchen. They do this by leaving a trail of pheromones – chemicals with a distinctive smell ants use to guide their nest mates to food. The shortest route to a destination will accumulate the most pheromone because more ants will have traveled back and forth along it in a given amount of time.

In the 1990s, computer scientists developed a class of algorithms modeled after ant behavior that are very effective at finding the shortest path between two or more locations. Like with real ants, the shortest route to a destination will accumulate the most virtual pheromone because more virtual ants will have traveled along it in a given amount of time. Engineers have used this simple but effective approach to design telecommunication networks and map delivery routes.

Photo by Carlos Pernalete Tua

Not only are ants good at finding the shortest route from their nests to a source of food, thousands of ants are capable of traveling along these routes without causing traffic jams. I recently began collaborating with physicist Oscar Andrey Herrera-Sancho to study how leafcutter ants maintain such a steady flow along their foraging paths without the slowdowns typical of crowded human sidewalks and highways.

We are using cameras to track how each individual ant responds to artificial obstacles placed on their foraging trails. Our hope is that by getting a better understanding of the rules ants use to respond to both obstacles and the movement of other ants, we can develop algorithms that can eventually help program self-driving cars that never get stuck in traffic.

Look to the ant

To be fair, there are plenty of ways ants are far from perfect role models. After all, some ant species are known for indiscriminate killing, and others for enslaving babies.

But the fact is that ants remind us of ourselves – or the way we might like to imagine ourselves – in many ways. They live in complex societies with division of labor. They cooperate to raise their young. And they accomplish remarkable engineering feats – like building structures with air funnels that can house millions – all without blueprints or a leader. Did I mention their societies are run entirely by females?

There is still a lot to learn about ants. For example, researchers still don’t fully understand how an ant larva develops into either a queen – a female with wings that can live for 20 years and lay millions of eggs – or a worker – a wingless, often sterile female that lives for less than a year and performs all the other jobs in the colony. What’s more, scientists are constantly discovering new species – 167 new ant species were described in 2021 alone, bringing the total to more than 15,980.

By considering ants and their many fascinating ways, there’s plenty of wisdom to be gained.

‘Silent Spring’ 60 years on: 4 essential reads on pesticides and the environment

Photo by Laura Arias, Pexels
Man Fumigating the Plants Laura Arias, Pexels

By Jennifer Weeks, The Conversation (US CC BY-NC-ND 4.0)

In 1962 environmental scientist Rachel Carson published “Silent Spring,” a bestselling book that asserted that overuse of pesticides was harming the environment and threatening human health. Carson did not call for banning DDT, the most widely used pesticide at that time, but she argued for using it and similar products much more selectively and paying attention to their effects on nontargeted species.

“Silent Spring” is widely viewed as an inspiration for the modern environmental movement. These articles from The Conversation’s archive spotlight ongoing questions about pesticides and their effects.

1. Against absolutes

Although the chemical industry attacked “Silent Spring” as anti-science and anti-progress, Carson believed that chemicals had their place in agriculture. She “favored a restrained use of pesticides, but not a complete elimination, and did not oppose judicious use of manufactured fertilizers,” writes Harvard University sustainability scholar Robert Paarlberg.

Rachel Carson. The author of Silent Spring (1962), the book that forced the nation to confront the toll of pesticides on the environment, Carson began her career with the U.S. Fish and Wildlife Service. A refuge on the southern coast of Maine now bears her name. (USFWS) (CC BY 2.0)
Rachel Carson. The author of Silent Spring (1962), the book that forced the nation to confront the toll of pesticides on the environment, Carson began her career with the U.S. Fish and Wildlife Service. A refuge on the southern coast of Maine now bears her name. (USFWS) (CC BY 2.0)

This approach put Carson at odds with the fledgling organic movement, which totally rejected synthetic pesticides and fertilizers. Early organic advocates claimed Carson as a supporter nonetheless, but Carson kept them at arm’s length. “The organic farming movement was suspect in Carson’s eyes because most of its early leaders were not scientists,” Paarlberg observes.

This divergence has echoes today in debates about whether organic production or steady improvements in conventional farming have more potential to feed a growing world population.

2. Concerned cropdusters

Well before “Silent Spring” was published, a crop-dusting industry developed on the Great Plains in the years after World War II to apply newly commercialized pesticides. “Chemical companies made broad promises about these ‘miracle’ products, with little discussion of risks. But pilots and scientists took a much more cautious approach,” recounts University of Nebraska-Kearney historian David Vail.

As Vail’s research shows, many crop-dusting pilots and university agricultural scientists were well aware of how little they knew about how these new tools actually worked. They attended conferences, debated practices for applying pesticides and organized flight schools that taught agricultural science along with spraying techniques. When “Silent Spring” was published, many of these practitioners pushed back, arguing that they had developed strategies for managing pesticide risks.

Archival footage of crop-dusters spraying in California in the 1950s.

Today aerial spraying is still practiced on the Great Plains, but it’s also clear that insects and weeds rapidly evolve resistance to every new generation of pesticides, trapping farmers on what Vail calls “a chemical-pest treadmill.” Carson anticipated this effect in “Silent Spring,” and called for more research into alternative pest control methods – an approach that has become mainstream today.

3. The osprey’s crash and recovery

In “Silent Spring,” Carson described in detail how chlorinated hydrocarbon pesticides persisted in the environment long after they were sprayed, rising through the food chain and building up in the bodies of predators. Populations of fish-eating raptors, such as bald eagles and ospreys, were ravaged by these chemicals, which thinned the shells of the birds’ eggs so that they broke in the nest before they could hatch.

“Up to 1950, ospreys were one of the most widespread and abundant hawks in North America,” writes Cornell University research associate Alan Poole. “By the mid-1960s, the number of ospreys breeding along the Atlantic coast between New York City and Boston had fallen by 90%.”

Bans on DDT and other highly persistent pesticides opened the door to recovery. But by the 1970s, many former osprey nesting sites had been developed. To compensate, concerned naturalists built nesting poles along shorelines. Ospreys also learned to colonize light posts, cell towers and other human-made structures.

Wildlife monitors band young ospreys in New York City’s Jamaica Bay to monitor their lives and movements.

Today, “Along the shores of the Chesapeake Bay, nearly 20,000 ospreys now arrive to nest each spring – the largest concentration of breeding pairs in the world. Two-thirds of them nest on buoys and channel markers maintained by the U.S. Coast Guard, who have become de facto osprey guardians,” writes Poole. “To have robust numbers of this species back again is a reward for all who value wild animals, and a reminder of how nature can rebound if we address the key threats.”

4. New concerns

Pesticide application techniques have become much more targeted in the 60 years since “Silent Spring” was published. One prominent example: crop seeds coated with neonicotinoids, the world’s most widely used class of insecticides. Coating the seeds makes it possible to introduce pesticides into the environment at the point where they are needed, without spraying a drop.

But a growing body of research indicates that even though coated seeds are highly targeted, much of their pesticide load washes off into nearby streams and lakes. “Studies show that neonicotinoids are poisoning and killing aquatic invertebrates that are vital food sources for fish, birds and other wildlife,” writes Penn State entomologist John Tooker.

In multiple studies, Tooker and colleagues have found that using coated seeds reduces populations of beneficial insects that prey on crop-destroying pests like slugs.

“As I see it, neonicotinoids can provide good value in controlling critical pest species, particularly in vegetable and fruit production, and managing invasive species like the spotted lanternfly. However, I believe the time has come to rein in their use as seed coatings in field crops like corn and soybeans, where they are providing little benefit and where the scale of their use is causing the most critical environmental problems,” Tooker writes.

California court ruling opens door for protection of insects as endangered species

Photo by Pixabay
Photo by Pixabay

By Liz Kimbrough, Mongabay (CC BY-NC-ND 4.0).

  • A court ruled this week that the California Endangered Species Act (CESA) can apply to invertebrates, including insects.

  • This means legal protections will be in place for four native, endangered bumblebee species in California.

  • The decision marks the end of a court battle between conservation groups and a consortium of large-scale industrial agricultural interests.

  • An estimated 28% of all bumblebees in North America are at risk of extinction, with consequences for ecosystems and crops, as one-third of food production depends on pollinators.

A California court has ruled that state legislation on endangered species can apply to invertebrates. The decision this week by the Third District Court of Appeal means insects, including four endangered native Californian bumblebee species and the monarch butterfly, will receive much-needed protection under the California Endangered Species Act.

“We are celebrating today’s decision that insects and other invertebrates are eligible for protection under CESA,” Sarina Jepsen, director of endangered species at the Xerces Society for Invertebrate Conservation, said in a press release. “The Court’s decision allows California to protect some of its most endangered pollinators, a step which will contribute to the resilience of the state’s native ecosystems and farms.”

In 2018, the Xerces Society, the Center for Food Safety (CFS), and Defenders of Wildlife petitioned the state of California to list four species of native bumblebees as endangered under CESA.

The California Fish and Game Commission voted to begin the process of listing these bees as endangered in 2019, but were then sued by a “consortium of California’s large scale industrial agricultural interests,” according to a Xerces Society press release. The trial court sided with the agricultural consortium, and the conservation groups appealed that decision in 2021. The decision this week marks a win for the conservation groups.

The four species are the western bumblebee (Bombus occidentalis), whose relative abundance has declined by 84%; the Suckley cuckoo bumblebee (Bombus suckleyi) which is considered critically endangered on the IUCN Red List and whose range has shrunk by 58%; the Crotch’s bumblebee (Bombus crotchii), now found in just 20% of its historical range; and Franklin’s bumblebee (Bombus franklini) which, despite extensive annual surveys, has not been seen since 2006.

Photo by Jiří Mikoláš
Photo by Jiří Mikoláš

According to California law, protections under the CESA mean that public agencies should not approve projects that would “jeopardize the continued existence” of any endangered or threatened species or adversely modify their habitat. These species are also protected from being removed from the wild or killed.

“It is a great day for California’s bumble bees!” said Pamela Flick, California program director with Defenders of Wildlife.

Sam Joyce, a certified law student with the Stanford Environmental Law Clinic who argued the case in the Third District, said the CESA is an important tool to protect and restore endangered species. He said the court’s ruling “ensures that CESA will fulfill its purpose of conserving ‘any endangered species’ by protecting the full range of California’s biodiversity, including terrestrial invertebrates.”

The IUCN’s Bumble Bee Specialist Group reports that 28% of all bumblebees in North America are at risk of extinction. Alarming on its own, this decline may also have consequences for ecosystems and crops, as one-third of food production depends on pollinators like bees.

“With one out of every three bites of food we eat coming from a crop pollinated by bees, this court decision is critical to protecting our food supply,” said Rebecca Spector, West Coast director at the Center for Food Safety. “The decision clarifies that insects such as bees qualify for protections under CESA, which are necessary to ensure that populations of endangered species can survive and thrive.”