I just saw another of those-Darwin Fish while traveling about. I've got to be straight with you-I can't stand them-and I find people who have them on their cars to be really annoying. What do you think? (If you have one-sorry-but what's your point?)
The following is from Wikipedia:
The Darwin fish is an ichthys symbol with "evolved" legs and feet attached and often with the word Darwin inside (like the ΙΧΘΥΣ or Jesus found in Christian versions). It symbolizes the theory of evolution, for which Charles Darwin laid the foundation, in contrast with Creationism, which is often associated with Christianity. Related to the Darwin fish is a fish with legs, the word 'evolve', and a hand that is holding a wrench.
The Darwin fish has led to a minor arms race in bumper stickers. A design was made with a larger "Jesus fish" eating the Darwin fish. Sometimes, the larger fish contains letters that spell the word "Truth." A further step shows two fish, one with legs labelled "I evolved", the other without legs labelled "You didn't". Another variant is the "ixnay" fish (a parody of "ΙΧΘΥΣ").