A key factor in many of these cases appears to be the strong social cohesion of toothed whales.
Prosqualodon was related to and looked like modern toothed whales.
Dolphin, a toothed whale that is related to the porpoise.
In general, three different types of sounds are produced by dolphins (and other toothed whales).
Narwhals, like other toothed whales, have big brains in relation to their body size.
Certainly over toothed whales, the dolphins, can produce loud sounds.
It is not yet known whether toothed whales regularly use such a weapon.
This is very different from the way that toothed whales eat.
Compared to toothed whales at that time, the squalodontids were likely more mobile.