Why did the boys sit apart?

From the text:

WE WERE SO HUNGRY that it hurt to drink water and we felt cramps in our guts. It was as though something were eating the insides of our stomachs. Our lips became parched and our joints weakened and ached. I began to feel my ribs when I touched my sides. We didn’t know where else to get food. The one cassava farm that we ravaged didn’t last long. Birds and animals such as rabbits were nowhere to be seen. We became irritable and sat apart from each other, as if sitting together made us hungrier.