It is strange to see ants carrying their dead comrades back to their nest, especially if there is no food in the dead ant’s body. It turns out, they have reasons why ants do it.
One reason is that the ant colony functions as a single organism, and all of the ants within it work together to ensure the colony’s survival.
Another reason is to keep their colony from being contaminated with harmful chemicals from rotting ant carcasses. Finally, it helps the nest clean and free of diseases.
What is Necrophoresis?
This is the process seen in social insects like ants to keep their colony clean. Ants have undertakers that specialize in taking dead ants back to their dumping sites called middens.
These sites are strategically located inside their nest or sometimes near the colony. It is also important to point out that there are situations in which worker ants carry dead ants too but with another purpose.
Why Do Ants Pickup Dead Ants?
Why do ants carry dead ants back to their nests? Some believe it is because they are paying their respects to the deceased. Others believe it is because they are trying to prevent the spread of disease.
Whatever the reason, it is clear that ants have a strong sense of community and care for their fellow members.
Undertaker ants carrying dead ants by their strong mandibles is a common sighting if you are near a colony.
While it might seem like a macabre funeral procession, the truth is this behavior has different purposes. Each purpose has one goal: to keep the whole colony (especially the queen) safe and healthy.
To Clean Up
As a colony, the most important thing for each member is to stay healthy by keeping the colony and its surroundings clean.
One way they achieve this is by immediately removing any dead ants and transferring the carcass to the midden.
In addition, by getting rid of dead ants, workers make it easier for other members of the colony to find food and perform their other roles.
While many other animals may leave their dead to rot or decompose in place, ants demonstrate a remarkable awareness of their larger social ecosystem, and moving the dead away from living areas helps create a healthier, more productive environment overall.
To Prevent Contamination
If an ant died within the colony and is exposed, it can start to rot and spread diseases. This would be disastrous for the whole community since it only takes one sick ant to potentially infect the rest of the colony!
So they immediately carry the dead ant to a dumping site that is sometimes located deeply below their nest. If an ant died naturally outside the colony, it is still likely to be carried by a worker ant or an undertaker back into its nest for proper disposal.
To further prevent contamination, ants like the Agentianina red ant won’t carry their dead comrade back to the nest if the body is already in the final stage of decomposition.
These species will just dump the body in their respective dumpsite that can be found outside the nest.
Another reason ants might carry a dead ant is to take it down into the midden, where it will live out the rest of its days among other deceased colony members.
Middens are usually located near the bottom of the nest, and they serve as both a graveyard and a garbage dump. Here, the corpse can decompose without posing any threat to the colony.
The disposal of the ant’s dead body in the midden is also to keep larger animals from finding their way to the nest.
In some cases, ants might also carry dead ants back to their nests as food. This is most common in smaller colonies or if the colony is facing a shortage of food.
When an ant dies, its body still contains nutrients that can be used by the other members of the colony.
The ant community will then collect the dead ants and take them to a specific area in the nest where they will be used as food. By eating the dead ant, its comrades can recycle its nutrients and use them to survive.
How Do Undertakers Know If an Ant Is Dead?
Ants don’t have good eyesight, so they don’t rely on their eyes that much; instead, they generally depend on their finely tuned odor receptors.
They use their sense of smell when finding food and even analyzing if another ant is dead.
Time of Death
Ants can determine the time of death of other ants by their smell. Once an ant dies, its body starts to decompose, and it will release a different scent than living ants.
This is why undertaker ants can identify dead ants and carry them back to the midden. It usually takes between 24 up to 36 hours before an ant can figure out if another ant is dead – and this is the kind of smell they have.
The Smell of Death
If an ant smells bad, it is likely that it has died and needs to be removed from the colony. Generally, when an ant has died due to natural causes, it releases a chemical reaction that smells like olive oil called oleic acid.
According to a study by W.O Wilson, the smell of Oleic Acid is equivalent to the smell of death for an ant. It is also an interesting fact that if you bathe an ant with Oleic acid that it will be as good as death for the other ants.
Nevertheless, there are also other smells that other species of ants produce when they die. Just like the Odorous House ant releases a chemical that smells like blue cheese when squished.
On the other hand, not all odor that ants produce is equivalent to death. Ants, such as the carpenter ants, release a vinegar-like odor when threatened.
Ants carry dead ants back for a few reasons: to prevent contamination, feed on them, and dispose of them in the midden. By doing so, they keep their colony clean and safe from disease and predators.
Deceased ants can contaminate the colony if they’re not properly disposed of, so the workers need to carry them away from the nest.
Ants also eat other dead ants as a way to recycle their nutrients and use them to survive. Finally, some ants are just placed in the midden to decompose without posing any threat to the colony. Regardless of the reason, it’s clear that ants have a complex system for dealing with their dead.