"... It was a while before he trusted me. Finally, I managed to communicate to him what I was after, and he's been helping me ..."
[Sirius Black in the chapter The Servant of Lord Voldemort]

This has been bugging me for a while: how can a dog and a cat communicate? Although Crookshanks is half Kneazle I doubt he'd be willing to work together with a dog.

Any ideas how this communication could work?

I don't think they would of been able to sit and talk like two people. It would of had to been through some type of telepathy. I do think animals can communicate with each other & other animals. Animals do communicate to people what they want without words.

I looked up telepthay and found this -anomalous cognition.
Anomalous cognition is a general term describing a transfer of information to a subject through currently unknown means. It fits descriptions of telepathy, extra-sensory perception, clairvoyance, precognition and other "perceptive" paranormal abilities. The term anomalous cognition is used by parapsychologists to reference awareness of information without having to specify or theorize a particular means by which that information was transferred.

Animagi can commuicate with true animals according to http://www.hp-lexicon.org/magic/animagi.html

Maybe this is where JK got the idea of how Sirius & Crookshanks could "talk". Who knows maybe "cat" doesn't translate clearly into "dog" and that is why Sirius had trouble at first.

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I'm a firm believer that animals can actually understand what humans say, they just do not have the ability to speak back.

So my guess is that Sirius eventually turned into a human.

i think maybe crookshanks is an animagus just a guess though lol

Crookshanks is NOT an animagus. JKR has spoken on it and debunked it.

i've formulated this idea.. consider it please.. PM me for your comments.. hehe
anyway remember when ron was buying scabbers rat tonic? crookshanks showed his agressions towards scabbers; maybe crookshanks knew that scabbers wasn't a true rat and knows his "TRUE" colors (wormtail!) so he knows scabbers deep down was a man hiding coz of cowardice.. so then sirius came along and revealed his plans against scabbers. and crookshanks of course agrees.. so they are in essence a duo fighting the dark side.. [ am i far]

That sounds really interesting and I'd say that it's a possibility. And I agree that animals can communicate with other animals and maybe that also works with animals and Animagi.

I think it's like someone has said if crookshanks actually saw through Scabber(wormtail) that day in diagon alley and any other day he went after him then there's no telling that he couldnt have told that sirius was indeed a human just transformed.

When haven't I sounded foolish ... LOL

I don't believe animals understand human speech. Human behaivor yes. If a cat (say a lion) growls at you ... you know you're dinner ... likewise if you come at a dog with a rolled up newspaper he isn't going to think you're going to give him a pat on the head.

That said, I don't think animals talk to each other verbally either, but if a mouse sees a snake hissing at it ... well no mouse is stupid enough not to understand danger.

My point, and I do have one ...

Sirius and Crookshanks, and even Scabbers for that matter, didn't verbally or (in my opinion) telepathically communicate anything. I think they just ... knew, neither of them liked Scabbers ... and they both knew why LOL obviously the cat, mouse, dog rivalry wasn't there otherwise the kneazle and the dog woulndt' have gotten along so well. A kneazle can't be that different from a cat right, then Sirius is a human/dog kind of person ... LOL

*complications* Aaaaaaaaaaaaaaaaaah *runs out screaming*

I have no clue ... but I think it was more based on their body language as animals act than speech or telepathy. Just a thought ... LOL told you all I sounded foolish.

The thing is anything is possible in the wizarding world! Even there, Crookshanks wasn't an ordinary cat...it said that somewhere in the book. In reality, some creatures can communicate with each other, such as whales using certain tones. Elephants have been proven to have this talent, as have dolphins, but it is not language as we know it, certainly.

they couldn't talk, but they had some other way of communicating.

Well, I think that since kneazles actually sense whether the wizard is "good" or "bad", Crookshanks was helping Sirius because he knew that Sirius was actually "good".
My guess would be that animals can communicate with each other and they have their own "animal" language. We know that Pettigrew can speak to other rats, so maybe cats and dogs can communicate also.

Well he could have bribed the cat or its just a thing of gainig trust plus there animals of cousre they can comunicate

Well, don't we already know that they weren't actually a dog or a cat?

Sirius was an Animagi dog and said that Crookshanks sensed that he wasn't really a dog. Crookshanks is only part cat, she is also part kneazle. And Kneazles are known for being very wise, intelligent creatures.

How did they communicate? Either by animal movements/instincts/sounds...or something else...

Crookshanks is only half cat, and the other half definetly has strong senses like that, and besides, Sirius isn't technically a dog, he's an Animagus.

I do believe in gernal animals can communiate within there species mostly using body language. Animals can communicate outside of their speicies in a similar. Look at the African planes, the Zebras, Gazelles and Wilderbeasts can all be seen grazing together. Birds are often seen on their backs picking off bugs. These animals can commuincate enough to understand that they are not a threat to each other and actually benefit from grazing together because their are more eyes to watch for preditors.

That being said, the HP world is not the Muggle world. The HP world has it's own set of unique rules. As we have seen repeatedly through the series just about anything is possible.

There is a way for animals to actually speak in the series. There is whole word used for that language... Parseltongue.

Parseltounge is the language of snakes. It is almost exclusively associated with Dark magic, and those possessing the ability to speak it ("parselmouths") are very rare. It appears to be a skill acquired not through learning, but through genetic inheritance or application of certain Dark magic. But the snake and the wizard speak to each other as seen throughout the series.

Harry is a Parselmouth. Other known parselmouths include: Salazar Slytherin and his descendants, including the Gaunts (Marvolo, Morfin, Merope), Lord Voldemort, and Herpo the Foul.

Dumbledore also seems to be able to understand Parseltongue. In HBP, when he repeats Morfin Gaunt's words "the big house over the way", which were spoken in Parseltongue. This means that either he himself is a Parselmouth or that he had previously viewed that memory with a Parselmouth who translated the conversation for him.

Fawkes does not have a lanuage associated just with Phoneixes but, he can understand Dumbledore when spoken to in English. In OoTP, Dumbledore asks Fawkes to warn him if Umbridge leaves her office. Fawkes does this by making one of his feathers appear with a bang in the office.

If these animals can communicate with wizards, I'm sure it can work with different magical species.

Also, Sirius was NOT genticly a dog. He was an Animagus. An Animagus is a witch or wizard who can turn into a particular animal at will. This ability is not innate: it must be acquired by magical means. Since there is only a handful of registered Animagus I would say it is not a common ability in the wizarding world. The most important thing to remember is that Animagi have full control over their transformations and retain all mental faculty, whereas say werewolves' transformations are involuntary and include severe changes in personality.

Sirius being a Animagus, combined with the fact that Crookshanks is NOT a cat but a Kneazle makes a world of difference.

A Kneazle is a magical cat-like creature closely enough related to cats to interbreed with them. Kneazles are considerably more intelligent than the average cat, and have a few knacks, in particular the ability to detect suspicious people (to whom they react badly). Crookshanks is half-Kneazle, which explains why he recognises Scabbers for Peter Pettigrew.

Sirius also suspected this.

Because Sirius, in his Animagus dog form and Crookshank, having Kneazle abilities, both had the same objective - get rid of Scabbers he is a bad wizard. They were united in this common goal and both had the same objective. Sirius being able to retain his sense of self while he is transformed into a dog allowed their communication to take place easier than your average Muggle cat and dog. Crookshanks would have been able to recoginze Sirius as a good wizard under the dog transformation.

In the world of magic, animals must be able to communicate. When the Maurauders transformed in order to help Lupin, they had to communicate somehow.

Everyone throw in an outrageous guess and we'll all have as much chance as being right as the next. Its the magic world after all so who knows. I think it would be from gestures, so a 'physical' communication kind of thing.
Like if two people who speak different languages try to communicate, you never know exactly what they're saying, but from physical actions you can get the jist of it.
Thats how i see it happening but obviously its a flat out guess. JKR might return to it in Deathly Hallows or maybe its just one of those things we weren't meant to think about

That's what I thought! For an animal, he seems pretty sure what he's doing, it's pretty strange to me...

Idk. Probably telepathy or maybe Crookshanks is an Animagus too.

I think in the Magical world anything is possible.

Crookshanks is half Kneazle, so he has some magical prowess as a feline. And I think because of that, Crookshanks knew that Sirius wasn't a real dog, so he trusted Sirius. And Sirius told Crookshanks all of his woes, and all of the things he was trying to do. And Crookshanks realized the truth of the statements, so he helped Sirius.

First of all, animals, not maybe all but most of them, do understand human's intention with our hormones released at that moment and with our behavious. Second of all, they do have a common body language. When an animal snarls, its not a good thing for sure.
And at last, *this is my thought*, magical animals can understand the country's language. Harry just says "go to Ron" to Hedwig and she delivers it. Harry talks to Hedwig and she understands most of it. Therefore Sirius transformed into human and told the situation. Also when he was dog, he used common body language. And I believe in that telepathy theory too.