Wham! Bam! Thank you, ma'am!
Boys will be boys! Androgyny in the dark ages & Gender-Bending for the workers
Foucault's theories should be a useful starting-point for this post. A visit to the magic site of David Gauntlett (an expert on Gender & Identity in popular culture) would prove most fertile for the academic & non-academic alike.
Mick Ronson was of course Bowie's most brilliant guitarist & arranger on his pivotal and career-forging records. Here he's getting the full publicity treatment, which bothered him. Less concerned with the semiotics of gender, he was disturbed (his mum’s house was daubed with homophobic graffiti) by the impact of this stage-behaviour on his musical credibility, since he considered these antics worthy of second-rate TV glam chasers, like the Sweet. Bowie, naturally, could see, semiotically, the value (cultural & commercial) of an androgynous image - and Mick's macho guitar/cock is swallowed wholesale by Dave!
It's an iconic image - what's interesting here is how much Bowie milked it, for this is a late Ziggy image.