London - Both sexes are less likely to recommend a woman for a job if it requires "brilliance", according to a study.
It also found girls aged five to seven were less likely to pick females for their team when told to choose "smart" children.
The study led by New York University asked more than 1 150 people to recommend two candidates for a job.
They were shown one advert requiring "superior reasoning skills", "brilliance" and "big, bold ideas", and another seeking "highly motivated" candidates with an "outstanding work ethic".
Men were less likely to choose women when the job was advertised as requiring intelligence, but surprisingly so were women.
The proportion of recommendations for women made by men fell from 33 percent to 31 percent for the "intelligent" job.
Two-thirds of women recommended other women for the "work ethic" job, but this fell to 54 percent when the position required "brilliance".
Similar results were seen in an experiment among 192 children, according to the study in the journal American Psychologist.
Senior study author Dr Andrei Cimpian said: "Women are members of our culture just like men are and they are not immune to the gendered associations that our culture attaches to the notions of brilliance and genius."