why do cats leave their mouth open after smelling a certain object  or other animal?
914014
its called a flehmen response it helps smelling certain substances. See link for info so I don't have to write it all here.
158064
Humans ask questions to communicate, to satisfy their needs, wants and curiosities. This may just be my opinion, but I think that animals ask questions. When your dog or cat goes to the door and scratches on it or whines, you know they're saying, "Can I go outside"? "Do you really want a cleanup in aisle #3?" When your dog gets his leash and brings it to you, you know he's saying, "Can we go for a walk, please". My mother had a goldfish that would come to the top of the water when he wanted to eat. Was he asking for food? HMMMM
326708
B/c they don't like the smell.. Now that's ironic
319997
actually, we have different kinds of taste buds that do different things. some are only there to move food along, others have pores which entrap food and absorb the chemicals to stimulate our sensory neurons. We use our smell as well because all foods have odors that are detected by the odorant binding molecules located near the nose, superior to the roof of the mouth. To sum up your question, it has to do with the odorants binding to the receptors in the nose to send messages to the brain and also the tastant molecules being mixed with saliva to dissolve the taste to send messages to the brain. the cerebral cortex/
3708
ants navigate and communicate largely by sense of smell.  they leave behind chemical markers that signify certain things - "food this way" or "danger" or whatever.  (this can be tested by you!  if you find an ant trail, put down a piece of paper and the ants will be lost!  eventually they'll make a new trail across the paper - which you can then move and manipulate where they go.)  \n\nthe antennae on their heads are their smell organs - so when they meet, the two ants communicate by smelling each other - kinda like dogs.
537973
Cat pupils close from the sides to centre in a vertical line... \nHuman pupils stretch and opens in a circle...
580665
If you mean What for: for smelling, that is, detecting and interpreting information from chemical cues that are abundant in the aquatic medium. Unlike the nostrils of tetrapods (terrestrial vertebrates), those of fish are not involved in breathing, but are associated with a chemosensory epithelium only.\n\nHowever, another answer to your Why question is: Because they're Craniates, and nostrils are a primitive feature for the group. All the craniates have a complex brain associated with three pairs of sense capsules: olfactory capsules (for smell, at the front of the skull), optic capsules (orbits and eyeballs) and otic capsules (inner ear). All these sensory organs have some type of opening to the environment to receive stimuli; in the case of the olfactory capsules, the nostrils are these openings. \nBeing a useful feature, it has been preserved throughout the Craniate --> Vertebrate --> Gnathostomate lineage.\n\nInterestingly, the water flow through the nostrils of sharks follows a defined direction, because there's a fleshy fold in each nostril that acts as a partial division between the inhalant current and the exhalant water flow. \nSee an illustration here:\nhttp://www.elasmoworld.org/biology/anatomy/shark/external/diagrams/nostril.gif
854000
Absolutely....they communicate with each other, as well as humans.  Maybe we can't tell exactly what they're saying, but they're trying.  My cats talk to me all the time, and just like a baby has different cries....my cats have different meows!
21042
Most definately. Probabaly the most easy way to prove this is to read on animal behavior in the subject of embarassment or anxiousness. Have you ever seen a cat that has tried to jump on top of something and they goof up? Some might lick their paw in a moment of trying to recover grace or run away out of embarassment. I think these reactions are key indicators of animal self-awareness.
230156
Yes! It happened to our cat when I was a kid. She had a litter (none of which survived) and a week later she had a normal, healthy kitten who lived to a ripe old age.
281215
There's a product called "No!" that will rid the smell from your door step and make them stop peeing there. the reason they do it is to mark their territory, and they keep doing it because every other cat is. You can find the product at the grocery store.
324504
the question is why do you smell your dogs butt?
838998
Mine does that too...don't know why we do it...maybe to close off our mouth as an airway?
423644
Most people are allergic to cats because of the oils that are produced by the cat's hair. It is a known fact that washing a cat's hair for several weeks will actually allow the fur coat to stop producing these oils. This happens because when you wash a cat, the oils are stripped from the coat, and eventually the coat just stops producing them (this doesn't hurt the cat in any way).\n\nOf course, the trick is getting your cat into the bath tub.\n\nI am allergic to cats but have owned two cats for the last five years. I don't take any medications, but if a cat hair touches my face, my eyes will flare up and it'll look like I'm crying. This is why I keep eye drops handy.
945965
Here's an idea: have your object be a mirror, or at least something reflective.  Animals always think they see another animal in a mirror.  Cats will react by arching, puffing their tails, meowing, and even charging the mirror.
1117669
Your cat will become clumsy. Those whiskers help your cat to feel tight spaces. The head leads the way, of course, and cats are no good at judging tight spaces by themselves, they're clumsy by nature. They need those whiskers to judge whether they're too fat to fit through the space. And, by the way, they do land on their back often enough. Probably more often than you have in the last six months....\n\nChipmunks, on the other hand, don't need big old whiskers, and are quite agile, and can stand up straight and drink out of a Coke bottle, if it happens to have a straw in it. But, we prefer Pepsi, if given a choice.
88528
It is an involuntary reaction.  I wonder if it is to keep our eyes from popping out!  But, really, that's just how our brain directs our bodies during such a complex human action.  Do animals close their eyes when they sneeze too?