Wee, I'll start. In the movie: Who was making the noise for help before the mayor's stapler incident? How did it reach Horton's ears before there was a special way for the sound to travel?
Maybe it was all the Whos freaking out all at once when it suddenly made that big swerve, or just Jojo testing his array in the observatory. Or maybe the world itself cried out. I dunno.
Maybe the "yelp" Horton heard was the Mayor calling for his assistant, Miss Yelp.
Dr. Larue, the doctor Mayor McDodd went to in order to find out what would happen to his floating speck of a world, starts to believe him later in the movie because of the unexplainable snow... yet does NOTHING when he's being ridiculed by the Council! She told him straight to his face that he was right about their world being in terrible danger, so why doesn't she step up and defend the poor man?
Maybe she was afraid of being ridiculed too?
Dr. Larue didn't have any proof that the mayor was right, either - she speculated that the existence of their world on a speck would lead to things like tremors and weather changes, but that doesn't mean the council would be any more likely to accept it as an explanation over her just getting worked up over nothing.
The Whos in a Flower Field
Vladd drops the flower into an endless field of flowers that all look identical. So why did Horton go through what was obviously an unrealistic task of finding that one flower with that one dust speck. No one else would have bothered. The speck was safer in that sea of flowers than standing alone on an easy vantage point on a cliff.
Horton was feeling protective of his tiny friends. He may have feared that Katie would later go find it and cause more harm.
They were just dropped from the height of a mountain! He probably wanted to make sure they hadn't died. Also, just before the clover was stolen from him the mayor was asking him to prove he existed; if he didn't find the clover again he's pretty much condemning his friend to look like a nutjob to everyone forever.
The clovers could eventually get eaten or even blown away as we saw.
How did he find out?
How exactly did Morton learn that Sour Kangaroo sent Vlad Vladikoff after Horton? (In the movie)
All versions of the story portray many of the denizens of the Jungle of Nool as loose-lipped yentas. It can be assumed that Morton heard it from a guy who knows a guy who knows a guy, etc.
Offscreen teleportation?
In the climax, how did Kangaroo and the residents of Nool get to Horton despite the fact that he destroyed a bridge earlier, and the only way to get to Mount Nool was across said Bridge?
Maybe the bridge spans a gorge that actually closes itself up somewhere further to the left or right. Horton was in a hurry and may have thought he didn't have enough time to go around.
Inconsistent Hearing
During the climax of the movie...The animals of the jungle are shown to be willing to listen when Horton claims to hear the Whos making noise, even though they can't hear it themselves. Why doesn't he just give someone the clover, go somewhere far away where he can't hear them, have them say something to it that he wouldn't know or be able to guess on his own, and then come back and have the mayor tell him what it was they said? Wouldn't that be sufficient proof that there were people on it?
It was too late. By the film's climax Sour Kangaroo had whipped everyone up into such a frenzy that there wasn't much Horton could do other than hold out until the Whos made enough noise to be audible. Plus, he's panicking. Perhaps if he had thought of that earlier it would have worked.
Vlad's Motives?
What exactly is Vlad Vladikoff's motivation? First he demands an exorbitantly high price—the Kangaroo's own baby!—but once she mentions hiring someone else he's so desperate for the job that he does it for free. What does he gain from any of this?
I think it's a matter of pride. Vlad is insulted when the Sour Kangaroo suggest she'll get the Wickersham brothers to do it instead. After all, monkeys aren't intimidating. Could be a Batman Gambit on her part.
It was a Batman Gambit. She wanted Vlad to do the job, but wasn't willing to let him eat her son for him to do it.
Jojo's dreams
It's made clear from the beginning that Jojo didn't want to become mayor of Whoville. So what DOES he want to be? Judging by all the musical instruments in his observatory hideout and his singing voice, I think it's safe to assume that he wants become a musician or singer.
It's also possible he hasn't actually decided what he wants to be yet, he just knows he doesn't want to be mayor.
Does Mom know?
So did Jojo's mother know what he was building in the observatory? She knows where he is when Nedd needs him during the climax, but that would imply that she knew he spent his time in the observatory. How did she find out about this if Jojo never speaks, and why was she okay with it?
He just never speaks to his dad because he doesn't know what to say. And she's probably OK with it because he's the oldest, so he might be seventeen or something.
Kangeroo was on that timing.
Why did the Kangaroo still try to dump the flower into the lava pot even after her son and all the animals heard it?
This could mean the movie version of Kangaroo is evil enough to want to kill an entire civilization just so she doesn't have to face being told she's wrong, meaning her later regret is about everyone ousting her more than what she almost did. More charitably, she might have been too swept up in the moment. She couldn't process at first that other people hearing the Whos meant there really was life on the speck, and instead could only grasp that she was losing control of the situation. A third, unlikely possibility is that Kangaroo has hearing problems and still couldn't hear the Whos even when everyone else could.
Note that her joey heard the Whos and stopped her, so, perhaps, Kangaroo is just poor at listening. The other animals heard the Whos when they listened close enough.
She did try to take the clover back from Rudy, but there’s no proof that she was still going to destroy it once she had it. It was more like a last feeble attempt to save face in front of everyone.
What was going to happen to Horton?
I’ve been wondering this ever since I was little and this applies to nearly all the versions. What were the animals going to do with Horton after they caged him and destroyed the flower? Leave him in the cage for the rest of his days? Let him out after a certain period of time? Or something else entirely?
Horton not taking advantage of his strength as an elephant
An elephant is physically much stronger than a kangaroo. Why didn't Horton use physical force against Jane?
Because violence would bring the wrath of Nool down upon him, and he'd be overwhelmed by sheer numbers, as seen in the climax.
