When Ace is at the crime scene after Roger Podacters murder, he comforts Rogers dog, who immediately starts growling the second Einhorn walks into the room. Ace jokingly chalks it up to the common theory that animals can sense evil. But after The Reveal, we know that the dog recognized Rogers murderer.
A minor one, but considering that even the dolphin started to puke when Ace revealed that Einhorn is a man, it does seem weird since it's implied that Einhorn slept with most of the cops in the precinct. However, dolphins are the only other animal besides humans that practice sex for enjoyment. Did the movie invert Bestiality Is Depraved?
Or a trained dolphin imitates what the people around it are doing because that's what a trained dolphin does.
He's rude and immature towards most people, while he's always kind to other animals. He has a reason to be when you consider how some people mistreat animals.
Dan Marino at one point asks Ace if he has any extra gum. Ace replies "That's none of your business, and I thank you to stay out of my personal affairs." To which Dan Marino replies "You are a weird guy, Ace!" This line seems to be just another example of Ace's general strangeness, until you recall why Ace was chewing the gum. He was trying to get the 'taste of Einhorn' out of his mouth. So, when Dan asked Ace for a piece, in order to prevent the next question ("Why do you have so much gum, Ace?") from even happening, Ace just immediately jumps into shutting down any further questions into his personal life. Ace basically didn't want to tell Dan Marino that he had made out with another man, so he shuts down the line of questioning immediately.
In Pet Detective, we never see how Ace escaped the shark he mistook for Snowflake. However in When Nature Calls, we see him brutally fighting a crocodile who gets so scared of him and tries to run for shore. Kinda makes you wonder what he did to escape the shark.
The possibility that Finkle might be the reason that Lois Einhorn (the missing hiker whose identity he stole) disappeared in the first place.
Highly unlikely, Since in the online script and a deleted scene, Ace tells Emilio the article is dated the very day before Finkle escaped.