Thursday, 12 January 2012

Ants and Ant-lions


I`m sure a lot of you have come across this innocent looking pit while exploring outdoors and have passed by it without giving it a second glance. The more exploratory among us, especially as kids couldn't just help but pour some mud into it!


But hey, what is this? Who made this pit and why is it so perfectly conical? Look a little closer and you may get a clue.


Hang on…its so perfectly camouflaged but there seems to be some creature at the bottom of the pit!


Zoom in …and there’s definitely something there!


Zoom in further…and uh oh…are those claws I see in there? They look evil!


Yes, those are definitely claws and it seems to be attached to something too! Now its really caught my attention.


But hang on, I`m not the only one who is curious here. There’s an ant come along who seems to be equally curious!


It is a small ant, too small to move the sandy soil as it walks. It pauses by the ledge of the pit and looks in.


Luckily for it, the soil doesn't budge and it doesn't fall in. It’s not sure what is there at the bottom of the pit. It could be food.


But it wisely decides against exploring further and moves away. An ant’s daily life is full of such decision making and taking the wrong one could mean the difference between life and death!


I look in another pit nearby and that should give me an indication of the fate of ants who were too curious around this pit. There’s an empty shell of a dead ant embedded in the soil just around the rim of the pit.


As I`m looking at this, along comes another ant. This one is far lager in size and is equally curious as to what lies in the pit. He bends inward at the rim to investigate further and then things begin to happen quickly... too quick for my photographic reflexes!


The soil gives way beneath its feet and the ant slides down to the bottom of the pit. It struggles on its way to the bottom, but each futile attempt to move up releases the loose soil around the walls of the pit and carries the ant further down to the awaiting jaws. Yes these are jaws not claws!


The creature with the jaws itself makes the situation worse by flicking soil upwards from the centre, causing something of a controlled mudslide bringing the ant closer towards the centre.


Then as soon as the ant is within grasp. the jaws lock on to the helpless ant and pull it down into its muddy deathbed.


The ant struggles while it can, desperately trying to release itself, but the grip is a death grip and it knows its fate is sealed.


The creature slowly drags the ant inwards and soon nothing is seen at the pit bottom. No ant and no jaws… The creature will soon suck the ant dry and cast its body out of the pit.


So, what exactly are we dealing with here? What is this creature? If you haven't already guessed by now, it is called an Ant-Lion. The ant lion is the larval stage of the ant lion fly.


The claw like protrusions are actually its jaws, attached to the creature’s head. The ant lion is also sometimes called the Doodlebug.


The above and below 2 images, were taken in reverse order and actually show the creature digging itself into the mud although it appears as if it is emerging from the mud.


This is because, the ant lion cannot walk forward. It can only move backwards! Thus, its posterior is used to push itself into the sandy soil, while the feet are use to flick sand upwards and help build the conical pit/trap, with the insect placed in the centre.


Below is the insect removed from the pit , highly magnified. Notice the toothed jaws and hairy body.


While the jaws make it hard for insects (ants) to escape their death grip, the hairs alert the ant lion about any movement within the soil around its pit, and prepare them for the possible feast!


When outside the pit, it is an amusing sight to see the ant lion walk backwards. A lay person will almost be convinced that its head its on its abdomen and is likely to thing that the head and jaws are the tail/abdomen.


The larva, will soon pupate and from the pupa will soon emerge the ant-lion fly. But that's another story which I hope to feature another time!

PS: Here is the photo of an adult ant-lion fly taken at night. You can see the mane like hair from which it derives the name –Lion: