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Discontent -

This lion looks like he's received some bad news. (Photo by Lemuel Butler)

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Agitated - Even a goose can get down and dirty when it wants to.

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Irate - This snake is slender, smooth, and sinister.

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Incensed - Here's the business end of an angry eel.

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Poker-faced - The day just doesn't seem to be going right for this fed up chimpanzee.

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Upset -

If you upset a hippo, they'll send in the heavy mob. 

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Disgruntled - Sometimes even a muscular, hefty English  bulldog doesn't like getting its paws wet.

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Bothered - You got something to say? This buffalo is in no mood for chit-chat.

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Piqued - This tiny hummingbird looks lost in thought.

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Bedraggled - This is what happens when a praying mantis forgets its umbrella.

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Miffed - I mean, did I ask for a shower? A picture that speaks volumes as to why cats don't like water.

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Bewildered - For this goldfish, seeing is believing!

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Morose - Has this monkey received some bad news or what?

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Dejected - Soaked through, this pony could probably use a towel and comb.

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Worried - Looks like this pug is waiting for its exam results. (Photo: Avigyan Chatterjee)

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Exasperated - A vocal zebra voices its displeasure.

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Outraged - An attacking swan doing its torpedo impression.

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Preoccupied - This young polar bear seems to have a lot on its mind.

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Marauding - Fancy an argument with this fuming mountain lion? Thought not.

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Overzealous -

An otter proudly shows off its new dentures. (Photo: Jason Hafso)

See also: Animals with the weirdest mating rituals 

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