Suicidal defense mechanisms

Ants have three main types of suicidal defense mechanisms. Firstly, the ants can essentially 'blow' themselves up in a process called autothysis. This is where an ant will contract its abdominal muscle that surrounds a gland. This gland will then burst, spraying a toxic, sticky substance everywhere that can kill and/or immobilize its predator.

The second defense mechanism is where one to eight worker ants, will shut themselves out of the nest at night. This will prevent nocturnal predators from infiltrating the nest and it basically means that the ants are committing suicide because they rarely ever survive outside through the night.

The third suicide defense mechanism is a preventative strategy. When an ant can feel itself getting ill from some type of pathogenic disease, it will leave the nest and go and die in isolation, in order to prevent the rest of the colony getting ill.

Mating in ants

Ants are social animals. They live in a highly organised hierarchical society. The mating ritual between ants is very brief. Firstly, the queen ant gives birth to several eggs which then go on to become worker, soldier, males or young queens. The workers are mostly sterile, however, in the summer, the young queens and males are released to mate with other ants. Once the mating has occurred, the male ant soon dies and the young queen then goes to start her own colony. This is where she will lose her wings, either through ripping them of as a source of nutrition or her worker ants will chew them off for her.  

Defense mechanisms

Ants have several predators, therefore, they have adapted several defense mechanisms and strategies to protect themselves against their enemies:

• Ants are equipped with a nasty sting/bite that secretes formic acid, which is highly irritant. 

• Some ants block the entrance to their nest with their head in a process called phragmosis. This prevents enemies form infiltrating the nest.

• Ants use their powerful mandibles to throw small intruders out of the nest and these mandibles can also snap shut when they are in defense mode. 

The fishhook ant

The fishhook ant can use its sharp spikes on its back to penetrate their enemies. It can also use these hooks to interlock with other ants in the nest. This means that the ants will form a sort of lattice which will prevent the ant from being dragged away by a predator.

Ant Predators

An Ant-eater breaking into an Ants nest

There are several animals that prey on ants. So much so, that they have been given the name myrmecophages, which literally means ant eater in Ancient Greek. Several insects, rodents and birds are opportunistic predators of ants which means they only eat Ants if they are given the opportunity. 

However, some animals rely on ants for their dietary needs. The large mammal, ant-eater even has a body that is adapted for breaking into ant nests. It has a long snout and sticky tongue, which makes it easy to suck ants out from tiny holes. It also has sharp claws and strong forelimbs to help it break down the ants nest. 

One unlikely predator of ants are black bears. It may seem silly for such a large animal as a bear to eat tiny insects such as ants. However, ants are social creatures and can live in nests from only a few members all the way up to a million members. This means that if a bear breaks into an ants nest, it can find several ants at a time, therefore, providing it with a large and nutritious meal.

Interesting Ant documentary

I remember watching this documentary last summer when it first came out. It is such an interesting depiction of ant life and is definitely worth the watch.

                                         

Myrmecophytes

An ant eating nectar from an extrafloral nectary.

Myrmecophytes are plants that have mutualistic relationships with ants. This relationship involves the ant protecting the plant from predators such as herbivores and in return, the plant provides the ant with food bodies or extrafloral nectaries which are highly nutritious to the ant. The plant also provides the ant with a place to live (a hollow structure called the domatia).

The ants may also feed the plants in a process called myrmecotrophy. This is where, the ants live on the plant, in the domatia. When the ant is living here, it produces piles of excrement and waste, which acts as nutrients for the plant.

Interesting facts about ants

I believe Ants are very fascinating creatures, they have a number of attributes, which makes them unique insects. Firstly, Ants can lift up to 50 times their own body weight! This is the equivalent of a fully grown man carrying a truck, with his teeth.

Secondly, for every human on the planet, there are roughly 1.5 million ants! This means that if every human being on the planet was put on a scale and similarly, every ant was put on a scale, the two scales would roughly balance.

Thirdly, Honeypot ants are eaten as a delicacy. These ants have large swollen stomachs full of nectar. This storage of nectar acts a emergency reserve for the colony during times of drought. The aborigine people of Australia eat this ant as a sweet because of the high amount of nectar.

What do ants eat?

An ant 'tending' to its aphids.

The diet of ant varies widely from species to species. Whilst some ants eat solely nectar, others may be predatory and eat other insects such as flies, beetle eggs and wasps.  However, a large amount of ants eat honeydew through a process called 'aphid farming'. Ants have a mutualistic relationship with tiny insects called aphids. These aphids eat the sugary fluid from the plant phloem. They then excrete a sticky substance called honeydew, which is effectively 'aphid feces'. Ants stimulate the release of this honeydew by rubbing their antennae on the aphids. In return, the ants provide the aphids with protection from other predatory insects.

Leafcutter Ants carrying vegetation back to their nest.

Ants also enjoy eating fungi. So much so, that they actually farm the fungi in their nests. Fungi-eating ants are called Attine ants and there are more than 230 species of them. Leafcutter ants are a popular type of attine ant. They use leaves and other vegetation as a substrate for their fungi-growing activities.

Myrmecochory

Myrmecochory is basically a fancy word for seed dispersal. Ants are widely known as seed dispersers and they provide seed dispersal tasks for more than 3000 species of plants. You may wonder why an ant would act as a seed disperser (what do they get out of it?). Well, almost all seeds have a fleshy nutritious part called an elaiosome. This elaiosome is rich in proteins, sugars and fats are provides a nutritious meal for the ant. The ant will carry the seed, using the elaisome as a handle and it will then take this seed back to its nest. Once the seed is in its nest, the ant will eat the elaiosome and the seed will then grow out of the nest. This is beneficial to the plant because once the seed is in the ants nest, the seed will have more chance of surviving till germination because the ants nest is in a seclude location, therefore, this location can protect the seed from predation by small rodents and environmental damage (fire etc.)

Why are ants so important??

Class: Insecta   Order: Hymenoptera

Ants are arthropods and there are roughly 12,000 species of Ants that vary greatly in their size, morphology and eating habits.  Ants are often called ecological engineers because of the variety of tasks they perform for our ecosystem. They have roles in seed dispersal, pollination, increasing nutrient in the soil and they have mutualistic relationships with several organisms such as plant, animals and microorganisms. Farmers have also been known to use ants as a biological Pesticide.