These days, about half of scientists who enter a scientific discipline go on to drop out after five years, according to a study published yesterday (December 10) in PNAS. In the 1960s, that half-life for scientists was seven times longer—35 years before they moved on to other professions.
“Entering graduate students should be aware of this, so that they would have realistic expectations and perhaps try to plan their lives accordingly,” study coauthor Staša Milojevic, associate professor of informatics at Indiana University, tells Inside Higher Ed.
The researchers used data from Web of Science to follow the publishing careers of more than 100,000 scientists in astronomy, robotics, and ecology from the 1960s to the 2010s. They defined a scientist’s entry to the field as the year he or she first published in the discipline’s principal journals and a scientist’s exit as the time when three years had gone by without any papers in these journals.
In addition to the decrease in career longevity, the researchers also noted a spike in the number of scientists who spend their careers in supporting roles—that is, not appearing as first or corresponding authors, an indicator of project leadership. The number of scientists who never led a paper rose from 25 percent in the 1960s to 60 percent in recent years.
“Altogether, the fraction of entering researchers who achieve full careers has diminished, while the class of temporary scientists has escalated,” the authors write in their study. They point out that until the 1980s (and the 1990s for astronomy), more than half of scientists had careers of 20 years or more, whereas that is no longer the case.
The researchers are not entirely sure what factors have caused this change, but it may have to do with the rise of “permadocs”—postdocs who do not go on to form their own labs—Milojevic tells Inside Higher Ed. Science increasingly depends on the work of these supporting scientists, yet the academic pipeline model has not adjusted accordingly, the authors write in their study. The university employment system calls for PhDs to conduct short postdocs, then pursue tenure-track academic jobs, yet that’s not what many scientists are doing these days, they write. “Instead, these support workers may be relegated to a series of short-term postdoctoral contracts or other forms of contingent academic work.”
“Our results suggest that, while essential, these supporting researchers are suffering from greater career instability and worse long-term career prospects in some fields,” the authors conclude.
One solution might be for institutions to use fewer postdocs and to establish more permanent staff scientist positions in labs, Milojevic tells Times Higher Education. Funders would accordingly need to support such positions.