At the risk of sounding trivial, this is my story: My principal supervisor has 3 of us all working in the same broad area. I started one semester ahead of two female colleagues. Though I have a working room next to my sup's office, I only consult about once in a fortnight when I have something solid to discuss, unlike my colleagues who are able to pop into her office almost daily or several times a day. They discuss, chat, have girl talk etc which I have no problem with except that they get to discuss my work too without my involvement while the reverse never happens. I then get comments related to my work from the grapevine or I eavesdrop. This way, I have even had to cede some of my initial objectives to them. Such is their influence. I understand the bonding coz, unlike I, they worked under the same Sup for their masters, but still it smacks of intrigue, competition and, though I hate to say it, even chauvinism (am male) hard to dismiss any more. How should I deal with this before it turns out to be a storm?

I quite agree there is a possibility that being male reduces your chance of engaging in the informal conversations to the same extent. The equalities agenda on gender generally only acknowledges discrimination can occur in one direction, which is of course quite wrong. I think you have a number of options: positively engage your supervisor or the other supervisees about their work on an informal basis, so you have the possibility to benefit from their work in the same way that they are from yours; you could ask for weekly/fortnightly/monthly team meetings for your supervisor and fellow PhD students and yourself to discuss where everyone is up to/collaboration opportunities; or insist that your supervisor does not disclose too much of your work and ideas/IP to fellow PhD students (in some competitive research areas this may be legitimate request though may damage your relationship with supervisor/fellow PhDs);

or move supervisors (clearly a bit drastic for the level of the problem at the moment, especially since you don't complain about the quality of your actual supervision in your post). I think that, while you may be right that you cannot engage in all the girly talk, everyone concerned would benefit from your participation in discussions about the general research area that you are engaged in, so you should try to find some mechanism (as outlined above, or another) to engage. In addition, do make an effort to talk to other academics in the department/university researching similar things to yourself and in other universities, to maximise on your understanding of developments in your research area.

Read the bottom post before the top post!

what exactly you are worried about. My basic question will be, do you think their mutual bonding in any way affects your outcomes.
are you concerned about a) unfair treatment because of possible favoritism...is the output of your work dependent on their work in some way. Do you think your supervisor is treating you unfairly e.g., not giving you fair opportunities or time or feedback b) or are you feeling socially isolated.(in-group out-group issues).. do you interact with these colleagues...how do they behave when you interact with these females...
I am not clear what is the basic issue here...

so are you not happy because your colleagues get on better with your sup than you do? i don't quite understand - if you think that is the case (maybe because they have known each other longer than you do) then why do you not pop around more often then? you could ask if someone fancies a cup of tea or if you could all go have lunch/dinner together because you think the group would profit from socialising more etc. you said you are right next door to your sup.

of course they're going to talk about work (too) when they're chatting with each other, that's only natural. it would be strange if they didn't. maybe you should come out of your office more often and socialise?

I think this is common then a team of people work on an overall project. I don't, but there are a couple of big projects like that in my dept. Clearly some people are more in the loop than others. The important thing is not to cede your project to the others, inch by inch. Now that you see the danger, you can better forstall this in future. Be clear about having your own bouned chunk of work.

it seems to me that the major problem is letting some of your thoughts "fall into the hands of" of your colleagues.. If you guys are working in the same small field, then your sup should know not to do that; if not, I think it is OK. About bonding, no tips ..