The article mentions the bystander effect (a psychological process whereby people can be reluctant to help others, because they don't want to get involved, or feel a sense of diffusion of responsibility in a crowd) to explain why people can ignore others in need. However, while there is a lot of experimental evidence to show that bystander apathy can be recreated in the laboratory, studies of behaviour in real-life emergencies is much less conclusive. Much work has been done by colleagues of mine into the bystander effect, such as Mark Levine (http://psychology.exeter.ac.uk/staff/index.php?web_id=Mark_Levine) who disputes simplistic interpretations of the bystander effect. He argues that we should instead focus on the situations in which we intervene to help others, and has produced a large body of evidence to show that if we feel a sense of shared identity and hence empathy with others, then co-operation is much more likely. Therefore, rather than bemoaning ‘human nature’ as inherently selfish, perhaps we should look instead at how we can encourage people to help others in need.
The work that I did with colleagues into crowd behaviour in mass emergencies (http://www.sussex.ac.uk/affiliates/panic/) did focus a lot on survivors’ accounts of 7/7, and we found that altruism was the norm and not the exception. We argued that this was because the emergency created a sense of shared fate amongst the survivors, which encouraged co-operative and not selfish behaviour. This is not to say that we don’t recognize that there were some incredibly heroic people who helped others in the aftermath of the explosions (I felt privileged to have met a few during my research in this area, and was moved and inspired by their accounts). However, the general mood of the situation (relative calm and/or shock amongst survivors rather than mass hysteria) meant that those brave individuals were able to step forward and encourage general co-operation through their actions. This was because they were seen as representative of this calm norm and so were effective in helping others and encouraging general co-operation amongst survivors. Had there been an atmosphere of mass panic amongst survivors, I doubt that such brave actions would have been so influential amongst others. Therefore, I would argue that when general co-operation occurs in mass emergencies (and when it is physically possible to do so, it generally happens), it is not in spite of the crowd, it is because of it. Therefore, emergency management strategies should take this into account, as survivors may be able to provide vital help in the time before the emergency services reach survivors in the aftermath of future emergencies.