That orca thing is actually crazier than how jarch explained it, I think it's 2 different groups of dolphins and a group of orcas. They all have their own languages but they have second languages to talk to each other and a 3rd language that all 3 understand. With dogs though I'm pretty sure they don't use human languages to talk to each other... so a dog from China will still understand a dog from Australia. Because their language is just basic gestures and sounds.. it's only the humans from other countries they wouldn't understand.