It's a well-known fact that dogs have tear ducts designed to flush dirt from their eyes, but this activity has never been linked with emotion - until now.
Professor Takefumi Kikusni decided to investigate after his poodle had puppies and he noticed that the dog's face changed when it pampered her babies. It had tears in it's eyes. Immediately, that clicked his mind. He started to ponder over that when humans are filled with emotions, they cry. Similarly, the case can be with animals too. He regards that the 'Oxytocin' hormone might be responsible for it. Oxytocin hormone is also known as the maternal or 'love hormone'. It is a known fact from the earlier observations that oxytocin is released in both dogs and their owners during interactions. Hence, an experiment was conducted that if the hormone necessarily brought tears in the eyes of dogs or not.
A researcher from Japan has concluded that the tear volume in the eyes of the dogs is much greater when the dogs reunite with their owners than it is when they meet someone whom they don't know well.
It's really very surprising to know that animals shed tears in joyful situations such as the case of reuniting with their owners. But then this very study by Professor Kikuski has green signalled the same. Although, the Japanese team hasn't responded to this research as they are still wondering to accept the cause of tears.
The truth can lie in any of the statements. But both of them convey about the certainity of the dog-human bond. It has also been proposed that this phenomenon may forge a deeper relationship with the dogs and humans.
It is possible that dogs show teary eyes while they enter into any interaction with humans. But then drawing an inference or running an approximation around it is in itself a win for all of us. It's a revolution indeed where the humans have started to understand the plight of speechless animals. It stands as a mutual victory in the arena of animal welfare.
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