Note: The regular daily commentary follows below this **** Special Feature! ****
Frequent commenter Daniel P made what seems a kind of back-handed compliment on Rivera’s drawing of a traditional Mark Trail image in yesterday’s strip as a “boomer” era version. But it reminded me that in a strip lasting over 70 years, images of characters can modify over time. Here are a few examples:

Making assessments from single images may not be fair, but they are still representative. Tom Hill was Dodd’s uncredited assistant who did lots of dailies from the 1950s on, so I’m giving him recognition. Elrod’s less animated and somewhat wooden model (c 1978-2013) was typical for him, while Allen (who seemed to favor a corner angle pose that made readers think he merely photo-shopped the image) returned to a more Dodd-like model, but gave Mark hair that was glued in place, as well as an expression that also seemed glued in place. Rivera’s original take on Mark Trail had a certain rough naturalism that she ultimately transformed into what we see today. Speaking of which, on to today’s strip!

We interrupt this adventure to bring you virtually the same information you saw in yesterday’s strip!

Every now and then Rivera feels the need to repeat content from the prior day, as we see today. About the only thing new is Forrest Trail’s “Elvis” sideburns. Yep, pretty wild, man.

Now, could Ed Dodd, Jack Elrod, or somebody actually named “Forrest Trail” have been involved in research that led to the EPA? I was not able to locate any citations.