Question

Why do snakes flick out their tongue?

( Only search mind not google )

Answer 1

Snakes are not able to breath in air through their nose to smell their prey.To do that ,they depend on a special organ called Jacobson's organ which is located deep inside the upper surface of mouth,which detects odours ,by flicking the forked tongue in and out rapidly,it picks up odour and puts it on to the jacobson"s organ .the amount of odour picked up by each tip of the forked tongue also provides information about the distance of the prey.

Answer 2

Snakes usually flick out their tongue to smell.

Let me be clear. Tongues of snakes don't have smell receptors.Tongue is an organ to collect the various smells or odors present in the air.
Once the smell is collected, these go directly to the receptor organ called Jacobson's Organ which is present at the roof of the mouth of the snake.Here, the collected odor is received and transformed into electrical signals  and then it is directed to brain that decipher what type and whose smell it is

So this is why snakes flick their tongue

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