Growing up with both parents as working scientists, I was blissfully unaware that there were battles over authorship of journal papers. I think there were two reasons for that: first, in those days single authorship papers were still quite common in neuroscience and second, my parents often jointly authored papers and they had their own modus vivendi as far as who went first and who went second.
Later in life, especially during my postdoc years at the NIH, it became abundantly clear to me that my early experience observing my parents was far from the norm. For one thing, it was during that period of time that multi-authorships became ubiquitous. For another, in neuroscience, three specific types of authorship took on mythological importance: first, last and corresponding. To explain, for our non-scientist readers, in a multi-authorship paper coming from a single large lab, first authorship is usually reserved for the trainee who actually conducted most of the experiments and analyzed the data. Sometimes, but not always, the first author is also the writer of the first manuscript draft. The last authorship is therefore typically reserved for the lab’s principal investigator (PI; the senior scientist who initiated and obtained the sponsored support for the research being described). Also, in most cases the PI is the one with the underlying idea for the scientific approach. Usually, but not always the last author is also the corresponding author–the person who is responsible for all communication about the manuscript with the editorial staff at the journal.
On a multi-authorship paper, the authors in the middle (between the first and last) are typically listed in order of their contribution to the body of research being described in the paper. Sometimes however the contribution to the work is close to zero. It has been the case that middle authorships are offered up for simply providing access to some experimental reagent…and sometimes as a political gift for some previous or hoped for favor. The PI is the arbiter of the author order for a single laboratory paper.
As is becoming increasingly common, multi-authorship papers sometimes represent a collaboration between more than one laboratory. In this case things get confusing and the potential for authorship wars grows quickly. There is only room for one last author, but there are several PI’s. Because the second to last author is the implied least important contributor, one can’t simply bunch the senior folks down at the end of the authorship list. The potential obvious solution of having one senior at the front and one at the end of the authorship list might work for a two lab collaboration, but clearly displaces the junior person who conducted the actual experiments. There is another serious problem with such an arrangement: there is the implication that the first author is a trainee of the last author. In other words, a first authorship on a multi-authorship paper is good if you’re a grad student or a postdoc, but bad (actually damaging) if you are a PI. This single issue causes most authorship wars.
For multi-lab collaborations the problem is even further exacerbated.
The peace is sometimes kept by using footnotes or a separate section of the manuscript to explicitly describe the role of each author in the body of the work. On other occasions authors are listed alphabetically with a footnote to that effect. These practices are excellent and have gone a long way towards ameliorating some of the vitriole.
Thinking of an authorship list as a string, sometimes a sub-string will be listed alphabetically implying equal contributions for those in the sub-string, but leaving the first authorship and last authorship roles clear. Alternatively, the second-to-last author will be designated the corresponding author with the implication that both the corresponding author and the last author are both PI’s who presumably are signaling their equal contributions.
There is an unspoken code among scientists about authorships (at least in neuroscience): a more senior author should be generous to more junior authors, particularly in being sensitive to their need to signal their independence as PI’s to promotion and tenure committees. Also, a more senior author should strive to avoid taking the first authorship position, particularly for a body of work within a single laboratory, since this not only displaces the trainee who conducted the experiments, but also leaves another trainee, awkwardly at the end in the senior author position (a mis-signaling). This avoidance of the first authorship position even holds when the PI actually conducted most of the experiments (but only on a multi-author paper from a single lab). In these cases, the PI takes the last authorship position, and “gifts” the first authorship to the trainee who normally would have been second. The core idea here is generosity. Those who have ought to be generous to those who don’t. In rare cases, where both the idea for the science and the work itself are the intellectual product of a trainee, the PI may actually remove herself from the equation, gifting a single authorship (and that’s a gem) to the trainee. This is a mark of being an excellent mentor and word of such generosity gets around.
What about those wars? When they do happen, they are nasty and brutish. The destroy friendships, slow down science and potentially ruin careers. They undermine the public confidence in science and support the cartoonish notion of scientists as petty narcissists. We are not, and so those authorship wars are to be avoided.