Yes!

By Date: Choose to view the most recent messages at the top or at the bottom of the page. Click Sort by Date at the top of the "Date" column to flip it.

As List or By Topic: Above the list of messages, click Group by Topic to clump messages into topics. In this view, above the list of messages, you can return to the basic list view by clicking List as Individual Messages. In the Group by Topic view, you’ve got a number of additional sort options that are explained here.

Groups remembers your sorting preference.

(Note: preferences are set on your browser and expire after seven days. As long as you visit the site at least once every seven days, using the same browser, you should not need to reset your preferences).