Proved. Plants can talk or communicate to each other by some unknown mode of communication. We had this art, but we lost it.

Proved. Plants can talk or communicate to each other by some unknown mode of communication. We had this art, but we lost it.
http://www.biomedcentral.com/1472-6785/13/19/abstract
Even light, and other communication mediums were blocked still, neighbouring plants could communicate with each other.
http://news.nationalgeographic.com/news/2013/13/130507-talking-chili-plant-communication-science/
In fact, in good old days, in India, Ex. Vikram Vetal tales, King Vikram talks to the walls and the doors...and these non-living doors, walls, windows could tell him, who lived their earlier, etc. Thus, this art was existing in the past that was documented as well. However, the science or art is lost when we could not preserve the all important knowledge.

Still there are evidences that few people in the world know the languages of animals and they communicate to each other.

Elephants communicate with each other:
http://video.nationalgeographic.com/video/animals/mammals-animals/elephants/elephant-gestures-play/
I also have met people in Madhya Pradesh, Karnataka and Kerala and Tamilnadu and even in Indonesia, who can/ could talk to elephants in their own but different language/s and understand each other. Any how those people who know the language of animals are not Harvard or MIT or Oxford or Cambridge or IIT or IIM graduate or any top University graduate world over, or Ph. D. like me, but they are not less literate is what I feel. They are Doctorate in their own field, if we recognize them, reward them, record how they do it, then learn from them, then only humanity will be benefited otherwise soon it will be a lost art or science. After, 50 years we'll again reinvent this wheel......thanks to humanity...for not respecting each other and spent time in war, hatred, egoism, egotism, and corruption. Long live humanity. Aum Shanti:...1....2....3.

Any how, if humanity loves to reinvent the wheel again and again and not providing such knowledge free of cost to needy then present science may also be lost if we stress too much on copy right, patent and all those fantastic business, before it reaches for the help of human kind.

Dr. Ashish Manohar Urkude,
ashish.urkude@gmail.com