Member Rara Avis
Marti, the list is pulling the information from everyone's Profile. If they haven't entered their birthday into their profile (and Marge hasn't), or if they entered it incorrectly (a handful of people put the month and year), they won't be in the list. I'm hoping, now that we have the page available, more people will start entering the data.
Oh, and for the record, the list also only includes Members who have posted at least 100 times and done so in the last year.