Crematogaster ants are found worldwide. They are also known as Acrobat ants or Cocktail ants because of their habit of raising their abdomen above their head, especially when disturbed or alarmed. Their heart-shaped gasters or abdomens have given rise to their other name, Valentine Ants. In comparison to other ant species, these ants are nothing more than a slight nuisance. However, if their colony is disturbed, they sometimes bite. There are various species of this light brown to black ant. Most species are arboreal and they are known as tree ants.
Crematogaster ants have an interesting interdependent sort of relationship with Rufous woodpeckers. The ants are an important part of the woodpeckers diet and help the bird during nesting. They build pagoda-style nests for Rufous woodpeckers, the size of a football. The ants make the nests by sticking together layers of dry leaves and mud with their saliva. The pagoda structure makes the nests so strong that they are not destroyed by heavy rains – in fact, the rain water flows down the nest without damaging it. The woodpecker makes an opening in the side of the nest and carves out a small chamber in the centre of the nest. While this building work is in progress, the ants do not attack the woodpecker, though some ant larvae get killed. Similarly, after the bird lays its eggs, it does not eat the ants in the colony; neither does it allow other woodpeckers to have a go at them.
What do the ants get in return for their labour? Food. When the eggs hatch, the woodpecker brings the chicks food. The ants gorge on the crumbs that litter the nest when the chicks feed.
Acrobat ants survive by preying on other insects, like wasps, termites and grasshoppers. They use venom to stun their prey and have a complicated trail-laying process to lead comrades to food sources. Acrobat ants can be found either outdoors or indoors. Outdoors, acrobat ants are usually inhabit trees but they often live in many damp and dark areas such as under rocks or piles of wood. Indoors, they usually build their nests around electrical wires in homes. These locations are often very near large food supplies and may be around other ant nests.
As with most insects that live and work as a cooperative group (eusocial), acrobat ants tend to form castes based on labour duties. This division is normally behavioural but also has a physical basis, including size and age. Soldiers are usually larger and equipped for finding food and protecting the colony. The worker ant is smaller than soldiers and queens, and its main task is to assist the queen in rearing the young ones.
Through a system of mutualism, plants provide shelter and food to the ants, while the ants provide protect the plants from individuals that might consume them. Many acrobat ants depend on plants such as Macaranga as their main source of food. They also fight away other herbivores that might come to eat up the plant. The ants become alarmed when the plant gets damaged or under attack. They at once come out from their plant shelter and become aggressive. They can also recruit other ants to help put up a defence.
The woodpecker makes an opening in the side of the nest and carves out a small chamber in the centre of the nest. While this building work is in progress, the ants do not attack the woodpecker, though some ant larvae get killed. Similarly, after the bird lays its eggs, it does not eat the ants in the colony; neither does it allow other woodpeckers to have a go at them.
Source: Read Full Article