It’s been over 80 years, but Abbott and Costello’s famous comedic skit “Who’s on First” lives on in our collective memories. Their increasingly ridiculous conversation about baseball and the name of the player on first base can still reliably produce a giggle in many circles.

But in the lab, questions about order can be anything but a laughing matter — particularly when it comes to the list of authors on a scientific paper. Many nonscientists don’t realize that, traditionally, the most important places on the roster are the first — indicating the person who conceived of and performed most of the research discussed in the paper — and the last — a hallowed place reserved for the senior scientist in whose laboratory the research was conducted.

In the biomedical research world, having many “first authorship” papers is largely seen as an indication of a scientist’s skill and tenacity; researchers with many “senior authorship” papers often garner a reputation of strong leadership and high productivity.

But as the National Institutes of Health and other funders increasingly reward collaborative research, and scientific projects grow more complex, determining authorship order is becoming less clear. Some are even venturing outside the lab to do so.