Memes y Mamas

As others said, it depends on the research field. I'm a biologist, and when I was a student, we needed to write a report about a certain worm of the phylum Nematomorpha that we found when doing field research. Turns out that the "most recent" references for Mexico about that group were from the 1930s! So I wrote to an expert from the University of Arizona (I think) and he confirmed my findings: there are almost no research about those worms in my country. So we completed our report with those old references and our teacher said it was good. In fact, in evolutive biology, systematics and taxonomy is not so rare to cite papers even from the 19th century, but surely we are an exception 🤷🏻‍♂️.