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Women can expect to be judged as less competent and receive lower pay than men in the field of science even when their qualifications are equal to those of their male counterparts, according to a Yale University study of undergraduate science students.

"Whenever I give a talk that mentions past findings of implicit gender bias in hiring, inevitably a scientist will say that can't happen in our labs because we are trained to be objective. I had hoped that they were right," Jo Handelsman, professor of molecular, cellular, and developmental biology at Yale University, said in a statement.

The small, non-random experiment found that science faculty at six leading universities were more inclined to hire and mentor male undergraduate degree applicants over female applicants when reviewing identical resumes where the only difference in credentials was the gender assignment.

"It is kind of scary that women receive less mentoring simply because of they're women," Handelsman told ABC News. "It makes me wonder about all the other impacts there might be because mentoring is a broad word for advising and responding and additional activities."

The study, which included 127 participants, assigned a summary to a fake, less-than-stellar applicant that was assigned the name John or Jennifer. The science faculty was asked to review the material about the male and female applicant for a laboratory management position. The bias against women happened regardless of the gender of the faculty member reviewing the application.

"The fact that faculty members' bias was independent of their gender, scienti?c discipline, age, and tenure status suggests that it is likely unintentional, generated from widespread cultural stereotypes rather than a conscious intention to harm women," according to the study published by the Proceedings of the National Academy of the Sciences this week.

On a scale of 1 to 7, women and men faculty members gave male applicants an average of 4, and the female applicants averaged 3.33 even though their credentials were identical.

Subtle bias even led to lower income for the female applicant. According to the study, the mean offered salary for the female applicant was nearly $4,000 less than that of the male applicants.

The mean salary offered to the female applicant was $26,508, while the male applicant received an average offer of $30,238.

"I think this shows just how subtle and pervasive these cultural stereotypes are," Corrine A. Moss-Racusin, a postdoctoral associate in MCDB and psychology, said in a statement. "There has been a feeling that women are underrepresented in the sciences because of personal or lifestyle choices, but it is clear that gender bias is also present."