It's unusual for a 'scientist' to be working alone now days. In academia it's fairly common for a single 'scientist' to manage 2-12 graduate and post doc students. And groups of 10's or even 100's of people working together on the same project is increasingly common.

PS: By 'scientist' I mean someone with a PHD doing research. Plenty of people do research that don't fall under that umbrella, but that's a side issue.