|Your new coworker?|
For over 150 years, fishermen and dolphins in a small village in southern Brazil have fished cooperatively. They work together to find and trap ocean fish (mostly mullet), splitting the catch. This system is the primary means of support for over 100 local families.
The dolphins and humans have developed a close working relationship. Some of the fisherman "report that their fathers and grandfathers fished before them, sometimes with the same individual dolphins". Because the humans know individual dolphins, it is possible to trace lines of descent: many of the dolphins, just like the fishermen, are following in their parents' "profession" (though it seems to be matrilineal for the dolphins).
Even though the dolphins work with the humans, they are completely wild animals. Fishing is controlled by the dolphins, and will not occur until one of the dolphins initiates it. The fisherman do not attempt to train or control the dolphins, and will never even try to touch them (as they don't want to "distract the dolphins from their work").
On both the human and dolphin sides, the fishing behavior requires a substantial amount of coordinated effort and communication (the dolphins use certain dives and other cues to "speak" to the men). Dolphins don't participate in the fishing until they are fully adult, suggesting that for them it really is learned and takes time to master.
The idea of humans working as equal partners with another species to complete a mutually-agreed upon task makes me feel really sentimental.