Cycling is very much a team sport. People take turns on the front to allow others to slipstream. Team members attack and force others to reign in the attack at the expense of tiring themselves out to prevent a breakaway. Hell, people even drop off to the back to pick up food and drinks for the sprinters / climbers / whatever to save them energy so they can better fulfil their role for the day. Perhaps the best example is the roll out train for sprinters. If you understand whats happening its like chess at 70kph, its amazing. It's a team sport through and through.