A former Princeton postdoc has sparked a soul-searching conversation among Ph.D. students with a blog post that criticizes the intensifying rat race for tenure-track faculty positions.

Ethan Perlstein, an evolutionary pharmacologist and until recently a Lewis-Sigler Fellow at the University, once clung to the dream of becoming a tenured professor, jumping through academic hoops and deferring the start of a family to make it a reality. But as he neared the end of his fellowship without an enticing college job offer, he decided he could not put his life on hold any longer with another postdoc position.

Perlstein now thinks he was naïve to believe he could sail into a tenured professorship simply by checking all of the academic boxes needed and apprenticing as a postdoc at top-tier universities.

“My ‘postdocalypse now’ post is a cautionary tale of expectations versus reality that I think is common among a lot of academic trainees,” Perlstein said, referring to his provocatively titled blog post that laments the increasing obstacles for life-science students in the chase for tenure.

Sarah Grady, a fourth-year Princeton Ph.D. student in molecular biology, also flirted with the idea of becoming a professor before ultimately realizing the tenure-track rigmarole was not for her. “I’ve seen countless friends and lab members go through the process of finding a postdoc, finding another postdoc, publishing as much as possible in a short time, and competing with hundreds of others for a single faculty position,” she said.

“While I agree that academic postdocs can be a worthwhile experience for some, the combination of low pay, long hours, and little opportunity for professorships makes the rarefied air at a major university a little more difficult to breathe,” Grady added.

Amir Roknabadi, a third-year Princeton Ph.D. student in molecular biology from Iran, has read Perlstein’s post and knows that he faces long odds. But Roknabadi can’t shake the dream of becoming a professor, which he believes would afford him the freedom to pursue his intellectual passions as no other job can. Nevertheless, he looks down the road with some trepidation.

“There are too many Ph.D.s,” ­Roknabadi said, and standing out in such a large group of impressive candidates requires not only hard work, note­worthy publications, and brilliance — but also plenty of luck.

A 2012 survey by the American Association for the Advancement of Science found that 56 percent of postdocs said they expected to get tenure-track spots, but only 21 percent ended up with one.

“The market is clearly not functioning properly because it seems to be more of a lottery, as opposed to a meritocracy,” Perlstein said. “At the point where you’ve reached an ­assistant-professor search, you’ve got people who survived college, graduate school, and a postdoc — and sometimes multiple postdocs.”

In the 2011–12 academic year, 53 percent of Princeton Ph.D. students in the natural sciences went on to become postdocs, according to University statistics. The figures were lower for other disciplines: 23 percent of doctoral-degree recipients in the social sciences, 15 percent of those in the humanities, and 24 percent of those in engineering reported taking postdoc positions.

Daniel Wright, a fourth-year Ph.D. student in environmental engineering who once yearned to become a professor, now is looking outside of academia. “You have the opportunity to get involved in bigger sorts of projects, potentially projects that involve many different people across many different disciplines,” he said. “When I realized that, the other stuff just fell away.”

That echoes the new attitude of Perlstein, who said he can have just as big an impact outside of academia, particularly by blogging and tweeting his ideas. “As I progressed toward a Ph.D., being a scientist meant being an academic,” he said. “Now I see that science is a calling, but ‘professor’ is just a job title.”