gnus-treat-date
gnus-treat-date is a variable defined in `gnus-art.el
'.
Its value is headDocumentation: Display dates according to the `gnus-article-date-headers' variable. Valid values are nil, t, `head', `first', `last', an integer or a predicate. See Info node `(gnus)Customizing Articles'. You can customize this variable. This variable was introduced, or its default value was changed, in version 24.1 of Emacs.