Ant-Icide: Can this Happen!!

These days i started to work late nights from my hostel.. previously i used to do that from my Department. As usual, before sitting infront of the computer, i brought a bottle full of "chilled water"... and kept it besides the CPU. After few minutes, i saw an group of Ants coming towards the bottle just like soldiers marching for a War. Being a kind-hearted person, i started to watch whats gonna happen. I was convinced that they are after that cold-water since its already mid-April and an evening walk in such a season is not a bad-idea. Few-minutes passed, meanwhile i was drowned into the magic of "e"nternet and forgot how's & what's happening around me. When i decided to sleep, i saw that so called Ant gang is no-more. Their dead bodies are lying near the bottle. I was pretty sure that this happened by mistake until the same thing repeated the other night. Then i decided to do an experiment on them. This time, no water bottle.. its just chilled water droplets on the surface. The result- surprisingly was same.. another Ant battalian comes and commits suicide. I doubt my room might be having a repository of Suicidal Ants. Whatever might be the reason... for now i believe that Ants commit Suicide atleast in my room...