How can I make cucumber with capybara and selenium fire Ajax on page load

Question

I have the following as a cucumber story:

@javascript
Scenario: Showing the page
  Given I am a logged in user
  And there is a member with a site 
  And I go to the home page
  .....

When that home page is loaded, there is a drop down that is populated via AJAX on page, in the selenium run browser test the

$(document).ready(funtion(){}) 

is not run and as such a drop down select that I need to use is not present. Is there any way that I can force Selenium to fire a javascript event for page load via a step maybe

When the page is loaded information about members is retrieved via AJAX

or something like that. I need that dropdown box, but due to some Action Caching in other parts of the application that use the navigation drop downs but should only sometimes have this extra drop down I load them in after with javascript, I can't really change that.

Any Ideas?

EDIT: It turns out I had set up some test data wrong and that was failing a condition for it, so it seems that as usual the library is fine and I made a mistake, so it seems this will be fine.