5 Things About Ants

5 Things About Ants

Strength

Ants are pound-for-pound, virtually at the apex for strength in the animal kingdom, carrying objects on top of them that range from around ~10-50x their body weights.

They have dense muscles with far greater cross-sectional area relative to mass for force production, which they can maximise in groups to carry even heavier items an individual could not. Having a tough exoskeleton armour casing also helps with weight resistance.

Moreover, ants have two sets of strong jaws, the inner for chewing and the outer for combat, digging and object manipulation/light carrying.

Colonies and Roles

Ants operate in colonies/formicaries; success is often down to their divisions of labour - behavioural specialisations to uphold systematic function. There is usually one queen ant as the largest, alongside thousands of females and males. Still, the queen has little control over the colony as an individual since their survival fitness is determined collectively as a group.

The largest groups are named 'super colonies', which can span hundreds and hundreds of kilometres, with a few hundred million individuals. Furthermore, they seem really intelligent for insects, at the top level up there with honey bees (they're in the same taxonomic order).

Their social systems are so complex, regarding group role organisation, distinguished physiologies, problem-solving and cooperation, that they're in the distinct category of 'eusociality' or 'superorganisms' compared to most of the animal kingdom. Ants can have ~250,000 brain cells, so a colony of ~40,000 can have as many, if not more than one human.

For roles, the queen's only job is to lay eggs, and the winged males/'drones' function only to mate with the queen; they are significantly weaker, smaller and have less disease resistance than females. The vast majority of females have it by far the toughest. They are the wingless worker ants that build and maintain the nest, forage, defend, plus care for the queen, eggs and larvae. All workers are infertile, so if the queen dies, the colony will likely as well (unless there's a princess next in line).

The foraging workers are specialised to feed other ants because they have two stomachs - one for themselves and another as a storage unit for sharing or 'trophallaxis'. It's usually a nice regurgitation or salivary secretion, yet the role structure helps with operational speed - like a forager going to feed a more nest-oriented worker.

Sensing and Communication

Ants have no ears or canals but can sense ground vibrations and air currents through their antennae feelers, body hair, plus the subgenual organ sensor between the foot and knee. It's probably intensified for ants with no eyes in order to compensate for lacking sight, picking up surrounding tactile cues for navigation and foraging.

They also seem to have a keen sense of smell, having their own unique scent, and the capability to identify colony foreigners. Most notably is the receival of chemical pheromone signals - maybe a warning concerning present danger or a message after death to move the body to a 'burial ground', for instance. Apparently, when one gets crushed, a different pheromone gets released that attracts at longer distances and sends nearby ants into turmoil; sometimes, ants utilise this or a similar odour to turn enemy ants against each other.

The crucial use of pheromones pertains to trails. They get left on soil, leading to food sources from their nest and are imperative in retaining organisation + direction. Finders deposit the route indicative of success when journeying back to the nest; others follow and will reinforce the trail until the food is gone and the pheromones dissipate.

Any changes, such as blockages, can be responded to by delving off the original route, identifying a more favourable new one that's faster to save energy, which could become refined over time to eliminate multiple, less efficient trails (vital to return back quicker to shelter in adverse weather because they can venture a couple hundred metres out from the nest).

If something happens environmentally for a trail to deviate away from the majority of the foraging group, an 'ant mill' could form (seen in army ants). They're basically a slow death vortex, where ants follow each other in a circle for hours until they may die from fatigue.

Zombie Ant Fungus

'Ophiocordyceps' is infamous for its alterations on ants' behaviour. The fungus appears as sticky spores that attach to ants, then germinating infective strands that breach the exoskeleton.

After the initial infection and a substantial fungal mass buildup, the pathogen exudes a scary amount of control over them, including the muscles, immune, and nervous systems - entailing some form of genetic suppression. It makes sense as effectiveness and efficiency get optimised for the infection to spread more in future.

The rough procedure occurs as the ant gets drawn away from the colony, often unreactive to other ants, existing pheromone trails and general stimuli. Then they typically reach a light, warm, damp and humid area, the perfect abiotic conditions for the eventual spores to thrive.

Subsequently, the ant climbs high up on vegetation and practically latches onto it permanently via manipulated jaw hypercontraction, otherwise known as the 'death grip' (the final action), only to wither away next. Later, a stem-like entity protrudes through the ant's head, and releases more spores. The height reached appears to be an adaptation to allow the fungal spores to cover a greater distance - increasing other potential transmission chances.

Although, some species can recognise it and either kill the infected or carry them away from the colony to reduce overall contamination risks (they avoid infected dead too). If deemed not too late, they can allogroom to remove spores before the process happens. Some may even adjust to living arboreally, avoiding the forest floor and reducing vulnerability to the spore spread range.

Farming and Slavery?

Honey ants most commonly farm aphids in a mutual relationship. As the 'hosts', ants promote the growth of the dependent 'symbionts' (the aphids), sheltering and protecting them from natural predators.

In exchange, ants get honeydew, a digestive byproduct of aphids, after they eat plant sap. It's a high energy source obtained when the ant taps the aphid's abdomen with their antennae.

More interestingly, however, there's slavery (yes, slavery), where some species invade others' colonies (sometimes waging war for weeks). They capture larvae and pupae, forcing them to labour and raise individuals that're unrelated. It's called 'slave-raiding', a form of social parasitism - usually targeted towards a single species; and performed by 'slave-maker' ants - a job role to replenish working forces.

Additionally, ants can steal eggs and eventually make the offspring work for them. So any imprinting seems to be a partial factor for why slaves stay slaves.

A noticeable aspect is how the slave ants are actually still treated as equals or superiors to their captors in social hierarchies (perhaps since they have a higher value for contributing more to the labour force). 'Permanent social parasite' ants rely on the enslaved for life (which sounds inferior to the 'inferior'?), mostly asking for food, whereas 'facultative' ones don't depend.