There's a lot of nice documentaries about it that you could watch like I did. Or I am sure that there are lots of articles or books written about it.
If you've watched them, you could just
tell me the answer and save me the time...
I am also certain that dolphins, porpoises, killer whales can converse in both abstract and concrete concepts based upon watching their behavior.
I am also certain that lots of animals can think in abstract concepts but they lack the ability to communicate very well so most of their thoughts are trapped inside their brain.
I'm curious as to how you're so certain about this. Certainly you can
conjecture about the possibility, and I can't say with any degree of certainty that you're wrong, but I'd like to hear your reasons.
Many animals can look at a problem and decide what tool they need and then they can go make that tool or find the tool and bring it to the problem and solve the problem with the tool. Thus proving that humans are not the only "intelligent" species.
Humans are not the only species that communicates with sound waves.
Humans are not the only species that uses tools.
Humans are not the only species that farms.
Humans are not the only species that engages in organized warfare.
Humans are not the only species that can navigate from point A to point B using measurements of distance and angles of travel.
Humans are not the only species with Emotions.
I'm not disputing that. However, all of those are very concrete concepts, and not evidence of abstract thought.
The main thing that gives humans their advantages is their hands. If Dolphins had hands then they would rule the world.
The thing is that you don't need hands and you don't need to accomplish world domination to demonstrate a human level of intelligence. Human amputees can do that. Do dolphins demonstrate abstract thought?
We also have an interesting mutation in our voicebox that gives us superior communication skills than any of the other animals with hands. Our hands give us superior writing skills too, which helps us to pass knowledge from one point to another which allows a civilization to develop.
So you're claiming that certain animals can converse in abstract concepts, yet their communications are too limited to allow them to demonstrate human levels of intelligence? And you don't need writing to pass on a culture; civilization predates the invention of writing by at
least 2,000 years, and various pre-literate civilizations have survived pretty much to the present day, or at least to within the last couple centuries. If dolphins were really that advanced, why could they not have developed a civilization using oral tradition? Humans can.