Ologies: Myrmecology (ANTS) with Terry McGlynn [podcast]

If you haven't tuned into Ologies, this episode is an excellent introduction. Host Alie Ward, a delightful science communicator, interviews various experts, infusing humor and informative asides throughout the episode. This particular discussion with an ant specialist opens the door to the intriguing universe of ants. Key insights include:

• Most ants' primary adversaries are other colonies of their own species.
• Argentine ants, an invasive species, have completely overrun the Los Angeles area, forming a super colony spanning hundreds of miles—though still smaller than the one in South America. More on this in the Kurzgesagt video below.
• Ants convey messages through chemicals, a process we are still striving to fully comprehend.
• When an ant is dying, it releases a chemical that prompts others to carry it to the "dead pile." If this chemical is applied to a healthy ant, its companions will likewise carry it away.
• All worker ants are female, while males, equipped with wings, exist solely to mate and subsequently perish.
• Army ants specialize in attacking and consuming other social insect colonies; see the additional Kurzgesagt video below for more insights.
• The queen is the colony's captive, as sisters share more genetic similarity with each other than the queen does with her offspring. The relatedness of ants is a fascinating topic, further explored in The Selfish Gene section below.
• Some ants cultivate gardens! Leafcutter ants manage fungus gardens akin to human farming practices.
• Certain ants even engage in ranching, nurturing aphids for honeydew, employing management techniques reminiscent of human strategies.
• Occasionally, ants may find themselves in a death spiral, following each other in circles until they perish.
• The most effective method to manage ants in your home is to allow them to consume the food they find, then track them back to their entry point and seal it.
• Experiencing a bite from a bullet ant feels akin to smashing your finger with a hammer at full force.

Kurzgesagt: The World War of the Ants — The Army Ant

Kurzgesagt excels in delivering concise educational content adorned with stunning visuals. This video highlights the ferocity and destruction associated with army ants, revealing:

• Ants have been around for approximately 160 million years.
• There are roughly 10,000 ant species.
• An estimated 10 quadrillion ants exist, translating to about 1.25 million ants for every human.
• The Army ant genus, Eciton, encompasses around 200 species.
• These ants do not construct nests and are nomadic.
• A single large swarm can eliminate 500,000 creatures in a day.
• They overpower foes through sheer numbers.
• Army ants refrain from battling one another, contrasting with most other ant species.
• Leafcutter ants create some of the most sophisticated social structures worldwide, featuring several specialized classes, including soldiers capable of defending against army ant swarms.

Kurzgesagt: The Billion Ant Mega Colony and the Biggest War on Earth

This title is no exaggeration. Ants genuinely engage in warfare with one another, with ongoing territorial conflicts occurring globally. The emergence of super colonies, facilitated by human activity, has amplified these confrontations. Key takeaways include:

• Linepithema humile, commonly known as the Argentine ant, is a modest yet incredibly successful species.
• They are smaller than fire ants and army ants but excel in adaptability, forming enormous colonies.
• Approximately one queen exists for every 160 workers.
• Their spread outside native regions began in the late 1800s due to human migration and trade. Competing colonies initially restrained each other's growth, but as a few queens established themselves in new territories, they formed a continuous colony without rivals.
• Different colonies may clash, so relocating an ant a significant distance away can integrate it into the same colony.
• Argentine ants have supplanted 90% of California's native ant population.
• Red imported fire ants are now gaining ground in the Southeastern US, presenting competition to Argentine ants.

Smarter Every Day: How to Get Ants to Carry a Sign

This brief video delves into the complexity of leafcutter ants in the Amazon Rainforest. Observing thousands of these ants marching at night with green leaf fragments on their backs, accompanied by smaller ants tending to the leaves, is truly mesmerizing. Noteworthy points include:

• Leafcutter ants seek sodium in their foraging.
• If you wish for one to carry a sign, simply apply a bit of urine on it—purely for scientific purposes, of course.
• These ants exhibit some of the most complex social structures apart from humans, maintaining their own small fungus gardens.

Science Vs: Ants — Tales from the Underground [podcast]

This episode features two compelling stories about ants. Highlights include:

• The adaptability of ants is illustrated through a narrative of thousands of ants that fell into a nuclear bunker devoid of food or a queen. Remarkably, this makeshift colony survived for years due to the continuous influx of new ants.
• Matabele ants exhibit altruism by rescuing injured comrades, showcasing the distinct nature of ant society. If an ant is severely injured, it refrains from signaling for help to avoid burdening others.

The Selfish Gene by Richard Dawkins [chapter 10 of the book]

The central thesis of The Selfish Gene posits that organisms, including humans, do not use their genes for reproduction; rather, genes utilize organisms to propagate themselves. The entire spectrum of life serves as a vehicle for gene replication, not the reverse.

Dawkins presents many intriguing insights throughout the book, but chapter 10, which examines social insects, is particularly captivating.

The peculiar behaviors and complex social structures of various ant species can largely be attributed to the sterility of worker ants.

> “The majority of individuals in a social insect colony are sterile workers. The ‘germ line’—the line of immortal gene continuity—flows through the bodies of a minority of individuals, the reproductives. These are the analogues of our own reproductive cells in our testes and ovaries. The sterile workers are the analogy of our liver, muscle, and nerve cells.”

Workers are essentially expendable.

> “The death of a single sterile worker bee is no more serious to its genes than is the shedding of a leaf in autumn to the genes of a tree.”

The genetic relatedness within a typical ant colony defies our conventional understanding of kinship.

To illustrate this point, consider how human reproduction operates:

Humans possess 46 chromosomes, essentially two complete sets of DNA (23 chromosomes from each parent).

If we denote one set of chromosomes from Mom as 1a, 2a, ... up to 23a, and the other from Dad as 1b through 23b, each gene for a trait—say, eye color—can be represented by two versions (9a and 9b). The dominant version dictates our appearance.

During the formation of sex cells (sperm or egg), a unique combination of one DNA set is generated, leading to genetic variability and predictable relatedness. Children share half their genes with their parents, and siblings also share half.

Ant reproduction, however, diverges significantly from this process:

This alternative structure results in unique outcomes, which Dawkins elaborates on:

> “A hymenopteran nest typically has only one mature queen. She made one mating flight when young and stored up the sperm for the rest of her long life—ten years or more. She dispenses the sperm to fertilize her eggs over the years, with some remaining unfertilized to develop into males. A male has no father, and each of his body cells contains only a single set of chromosomes (all from his mother), unlike humans who receive a double set. A female hymenopteran possesses both a father and the usual double set of chromosomes. The developmental fate of a female—whether she becomes a worker or queen—depends not on her genetics but on her upbringing, particularly on the type of food she receives.”

Male ants lack fathers, potentially leading to awkward explanations.

Another consequence of this reproductive strategy is that sister ants share a unique degree of genetic similarity. Males and the queen share half their genes, queens and daughters are half-related, and sisters are actually three-quarters related.

This genetic structure leads scientists to believe that worker ants exert control over the colony, rather than the queen. Workers are more closely related to one another than to the queen, motivating them to utilize the queen for producing more of their own kind.

> “A gene for vicariously making sisters replicates itself more rapidly than a gene for making offspring directly. Hence, worker sterility evolved. It is presumably no accident that true sociality, with worker sterility, seems to have evolved no fewer than eleven times independently in the Hymenoptera and only once in the entire rest of the animal kingdom, namely in termites.”

The notion of countless sisters compelling their mother to produce more siblings is perhaps the most astonishing revelation about the ant world.

The truth is often stranger than fiction

It's no surprise that many science fiction authors draw inspiration from ants and other social insects when creating alien species. The xenomorphs from the Alien franchise immediately come to mind. Yet, the more I learn about social insects, the more I prefer the fictional terrors crafted by authors over the reality of being miniaturized and placed within an ant colony.

Originally published at https://www.hurtyourbrain.com.