Breathing and the word choice
In January two thousand twenty-six, the question keeps coming back: do animals ever choose to die on purpose? The idea is often attached to two very different animals: dolphins, who must surface to breathe, and army ants, who can get trapped in a moving circle sometimes called a death spiral.
Key Takeaways
Breathing in one clear frame
- In science, “suicide” usually means intention: planning or choosing death as a goal. That is hard to prove in nonhuman animals.
- Many animal deaths that look like suicide can be explained by stress, illness, confusion, accidents, or forced behavior.
- Dolphins do not breathe the way humans do. They surface for air in patterns, and they can sleep in water in unusual ways.
- Army ants can form a “death spiral” when simple follow-the-scent rules loop into a circle and the column cannot break out.
- Some social insects die while defending the colony, but this is better described as sacrifice shaped by evolution, not a personal decision.
Story & Details
Breathing, intention, and what counts as evidence
The hardest part is the word itself. “Suicide” is not just dying. It is dying with a goal in mind. In humans, that can be described in words, planned, hidden, and repeated. In animals, those signals are rarely available. A single dramatic death, even a sad one, does not automatically show intention. Scientists look for patterns that are hard to explain by pain, panic, or simple reflex. They also look for alternative causes first, because many forces can push an animal toward death without any “wish” to die.
Breathing on purpose: what dolphins really do
Dolphins are mammals that live in water. They breathe air through a blowhole. That means a dolphin must surface, open the blowhole, inhale, and then dive again. This can look like “choosing to breathe,” because the timing is controlled and visible. But controlled timing is not the same as a conscious decision to live or die. Dolphins also have special sleep patterns that help them rest while staying safe. A well-known feature is that they can show sleep with one side of the brain at a time, which supports long periods of vigilance in water.
This matters because popular stories sometimes claim a dolphin can “decide” to stop breathing in the same way a human can decide to hold his breath. Physiology is more complex than that. Dolphins can hold their breath for long dives, and they can change breathing patterns with stress or training. Yet breathing is still tied to core brain and body systems that react to carbon dioxide and oxygen levels. A change in health, environment, or stress can shift these patterns without any clear evidence of intention.
A famous captive-dolphin story, and what it can and cannot prove
One widely repeated case centers on a dolphin named Peter, linked to a dolphin communication project in the United States (North America) during the nineteen sixties. The story is often told in a romantic and tragic way. It includes claims that the project blurred human-animal boundaries, including reports of sexual contact between a human caregiver and the dolphin. Later accounts describe Peter being moved to a different facility, deteriorating, and dying. Some retellings call it suicide, often by saying he “stopped breathing.”
That last jump is the key problem. A dolphin’s death after upheaval can fit many explanations: stress, reduced space, illness, changes in light and routine, and social disruption. Even if the final moment involved a failure to surface, that does not prove the goal was death, and it does not prove the cause was longing for a particular human. It shows something real and sobering: captivity and disruption can push a highly social, intelligent animal into a state where health collapses. But it does not give clean evidence of suicide in the human sense.
The death spiral of soldier ants: a trap made of rules
Now shift to ants. “Soldier ant” is a common name people use for the large workers in some species, and it is also used loosely for army ants and driver ants. The death spiral story is most closely tied to army ants: ants that move in huge columns, often with limited vision, following chemical trails.
The spiral begins with something small. An ant follows the scent of another ant. Another follows him. In a normal raid, that forms a useful path from the nest to food and back. But if the trail bends into a loop, the same simple rule can turn deadly. Ants keep following the strongest scent, and the strongest scent is now the circle itself. The result is an “ant mill,” a moving ring of bodies that can keep turning for hours. Some ants may escape if they break the trail and find a new scent path. If the circle stays strong and the environment offers no break, exhaustion and dehydration can kill many of the ants.
This looks like self-destruction from the outside. Inside the ant’s world, it is closer to a software bug than a plan. The ant is not trying to die. The colony is not “deciding” to sacrifice these workers. A useful collective rule has fallen into a bad loop.
“Suicidal” sacrifice in insects is usually colony logic, not personal choice
There are also insects that die while defending the colony. Some ants can rupture their own bodies to release sticky or toxic substances against enemies. The act is sometimes described as “suicidal defense,” because the worker dies. But the best way to understand it is evolutionary: the worker’s body is being used as a one-time weapon to protect relatives and the nest. It is sacrifice shaped by natural selection, not a private mental decision.
A similar point applies when parasites change behavior. In some ant species, a fungus can hijack the ant’s movements so the fungus can reproduce. The ant’s death may look like a deliberate march to doom. In reality, it is forced behavior driven by infection.
Conclusions
Breathing as a clue, not a verdict
Dolphins and ants both show how easy it is to project human stories onto nonhuman bodies. Dolphins surface to breathe in visible, timed patterns, so their deaths can feel like choices. Army ants follow scent rules in massive crowds, so their fatal loops can feel like group madness. But intention is a high bar. In January two thousand twenty-six, the most careful reading is still this: animals can die in ways that look self-caused, and some species can die while defending others, yet clear evidence of suicide as a conscious goal remains rare and contested. The better questions are often simpler: what pressure, what rule, what injury, what environment made death more likely?
Selected References
Breathing and evidence, in public sources
[1] https://pubmed.ncbi.nlm.nih.gov/18232440/
[2] https://www.fisheries.noaa.gov/insight/understanding-marine-wildlife-stranding-and-response
[3] https://pmc.ncbi.nlm.nih.gov/articles/PMC8665646/
[4] https://www.theguardian.com/environment/2014/jun/08/the-dolphin-who-loved-me
[5] https://pmc.ncbi.nlm.nih.gov/articles/PMC261877/
[6] https://pmc.ncbi.nlm.nih.gov/articles/PMC5919914/
[7] https://www.youtube.com/watch?v=JsfiUR0ZzLw
Appendix
Breathing glossary, A to Z
Ant mill: A circular loop of ants that forms when trail-following rules lock into a ring, making the group keep walking in circles.
Autothysis: A defensive act in some insects where a worker ruptures his own body to release substances that can trap or harm an enemy.
Breathing (Dutch): Used for simple talk about breathing in daily life. Sentence: “Ik adem.” Whole-sentence use: a plain statement of breathing. Word-by-word: “Ik” = I; “adem” = breathe. Natural variant: “Ik adem in.” Word-by-word: “in” = in. Another common sentence: “Ik kan niet ademen.” Whole-sentence use: a basic statement of inability. Word-by-word: “kan” = can; “niet” = not; “ademen” = to breathe.
Cetacean: The animal group that includes dolphins, whales, and porpoises.
Death spiral: A common name for an ant mill when the loop persists long enough that many ants die from exhaustion or lack of water.
Destructive disinfection: A colony defense behavior where ants reduce disease risk by attacking infected brood, often harming the infected individual to protect the group.
Dolphin sleep: Rest in dolphins that can include one-brain-hemisphere sleep patterns and other strategies that allow surfacing and vigilance.
Inclusive fitness: An evolutionary idea that a trait can spread if it helps relatives survive and reproduce, even if the individual worker pays a high cost.
Ophiocordyceps: A group of fungi known for infecting insects and altering behavior in ways that help the fungus reproduce.
Pheromone trail: A chemical scent line laid by ants that guides others to food, safety, or nest routes.
Self-destructive behavior: Actions that lead to death or harm without clear proof that death was the goal, often explained by stress, illness, confusion, or manipulation.
Stranding: When a marine animal ends up on land or in shallow water and cannot return to open water without help, often linked to illness, injury, navigation issues, or environmental stress.
Suicide: In the strict human-centered sense, death with intention as the goal; in animals, this is difficult to demonstrate with strong evidence.
Unihemispheric slow-wave sleep: A sleep state where one brain hemisphere shows sleep-like activity while the other remains more wake-like, seen in several marine mammals.
My Diary - Leonardo Cardillo 