The science shirt strikes me as extremely derivative, if not an outright rip off, of Zach Weiner's design at smbc. Most obviously visible at his kick starter here:

Which, I'm pretty sure, was also an original comic on his site. I'm sure this was an accident- you can't check the entire internet for every shirt every day- but you should take this one down and put up tomorrow's. He's an artist who makes his living selling swag for his artwork online. Don't eat his cake.