Boise Ed submitted this Carpe Diem as a CIDU, commenting: “There’s a stereotypical guy stranded on a tiny island and a ship passes by. We’re supposed to laugh at this? The boat is labelled ‘United Bananas’, so that apparently has something to do with the apparently intended humor.“
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P.S. At first I was completely puzzled and in total agreement with Ed, but only after I created this post (and examined the comic about a dozen times) did I finally discover the critical detail. Now I feel pretty silly (and I understand why this didn’t get posted before), but I’m still not going to reveal the answer.
Comics I Don't Understand 
Oh. I think I get it now, but I won’t spill the beans. The devil is in the detail.
Oh. I think I get it now, but I won’t spill the beans. The devil is in the detail.
The art doesn’t make it easy to figure out the joke, unfortunately, especially at the unnecessarily tiny size.
If the man, his island, and the tree were looming large in the foreground, with the ship seen over his shoulder, I think it would have been very clear.
Another problem is the tree is the wrong kind.
There was just one banana (growing from a palm tree, as larK points out). And the boat has taken that banana, but has not picked up the shipwrecked guy. Hey, it’s just business.
Reading your comments, at first I wasn’t sure what “tiny detail” y’all were talking about. The fact that the banana is missing in the second panel is literally the first thing I saw, before I even noticed the words on the ship. Heck, the banana is almost half the size of the guy.
Might be because I’m on a computer and some of you are on your phones. Or maybe I just notice weird things, I dunno.
I spotted it pretty quickly but I do think the evening scene combined with the wrong tree kind of makes the banana look like a crescent moon rising.
That’s the typical stranded-on-an-island-trope tree.
(Banana for scale).
Leave the guy, take the banana.
Many people have a banana hanger in the kitchen. He uses the tree as a banana hanger and he is down to his last banana. Or was until it was taken from him.
Xine Fury (6): It’s hard for me to imagine reading comics or watching movies or sports on that little phone screen, but I know some folks do that.
Andrew Millar (7): That’s exactly how I first saw it, as a low moon crescent. Its subsequent absence just seemed to indicate that some time had passed.
Day-o. Day-ay-ay-o.
I have used the phone to read comics while waiting somewhere. I hold it sideways and expand the image, panning if needed. It’s not my preferred way, but it’s serviceable.
How does one use a banana hanger with one banana?
@Boise Ed: You start with two bananas hanging on the hanger and you remove one banana by breaking it off below the stem.
With a banana hammock.
Ah. I guess it helps if you really enjoy Slylock Fox.
I don’t really enjoy Slylock Fox.