After sitting on a series of all-male conference panels, Owen Barder started answering speaking invitations with more than a “yes” or “no”. “I got into the habit of writing back and saying: ‘Have you thought about inviting a woman instead?’” says Mr Barder, director of the Center for Global Development in Europe, a research group.

He is not alone in pointing out the predominance of conference panels consisting of men. Hundreds of posts submitted to a Tumblr social media account show photographs of all-male panels. Accompanying each post is the headline: “Congrats, you have an all-male panel!” along with an ironic depiction of masculinity in the form of actor David Hasselhoff giving a thumbs-up.

The dearth of women in public speaking reflects broader issues, from the lack of female chief executives to the predominance of men on corporate boards, particularly in industries such as technology, engineering, investing and financial services. “Historically men have dominated panels, and this isn’t surprising when you look at senior leadership in organisations and see mostly white men,” says Anna Beninger, research director at Catalyst, a non-profit body dedicated to promoting workplace diversity.