This fellow/fellerette is a "great gray slug" (and I need to do some of my own --non-copyrighted-- photography of the slug critters who crawl up onto our porch).
There are several nice sites which describe the commonly known characteristics of these humble creatures, like:
--but what I'm interested in presenting here is their amazing features, such as the unusual qualities of their slime, their adaptability, and their (apparent) ability to simply know where there's food and water:
This has happened several times on our porches, --
--and probably most every time, had I been paying attention. What gets to me is that straight line of purposeful travel, even to climb up the side of a box we put on the porch --in hopes of defeating the slug's food homing "system".
How do they do that!?!?
Maybe the Wiki will eventually tell us:
(Goodness -!- but this is a short web page.)