I work with a senior researcher who, in my opinion, has strange views on author order. To be clear- I really don't care and there isn't conflict here but I find the situation strange.

I am a PhD student and I work with some scientists at a US national lab. I am my advisor's only grad student, and I am the only student in the group at the national lab if that matters.

We are preparing abstracts for an upcoming conference, where there is a different member of the group being considered the senior author depending on the topic of the abstract. The thing that I find strange is that one senor researcher wants to be listed last on the abstract where they are the senior author, and the other wants to be listed second and claims that's how it works in their field of electrical engineering. As a result, there are two abstracts being submitted on very different topics with the same name being listed last. On one of those the last author contributed very significantly, whereas on the other they contributed...enough to be listed as a co-author.

Anyone hear of this? Again, I really don't care since my name is where it belongs (imo) on everything and nobody else seems to have a problem other than finding it odd, but I was wondering if anyone had any insights.