Just like people across the United States all speak English with their own regional quirks, it turns out sperm whales living in different parts of the Mediterranean may be speaking the same whale language with regional variations. According to a new study published in the Proceedings of the Royal Society B, whales in the eastern and western Mediterranean appear to have developed distinct dialects.

Researchers analyzed more than 5,200 recordings of sperm whale “codas,” which are the rhythmic click sequences whales use to communicate. They were collected over nearly two decades in the waters around Spain’s Balearic Islands and Greece’s Hellenic Trench. Whales on both sides of the Mediterranean were fans of the same basic four-click pattern, but eastern whales delivered it at a much faster rate than their western relatives.

Mediterranean Sperm Whales May Speak With Different Accents, Study Finds

The best way to think of it is not as two languages but as someone with a deep Valley Girl California accent talking to someone with a thick Boston accent. Same language, different interpretations.

These whale dialects help organize whale society. These social animals form family groups that belong to larger “vocal clans,” and whales usually prefer associating with whales that speak their dialect. If it sounds remarkably human, it is, right down to how these vocal traditions are learned and are not genetically inherited.

The researchers think that Mediterranean sperm whales first arrived in the area around 20,000 years ago and eventually spread eastward. Those eastern populations became isolated, and their dialects gradually diverged from their western counterparts while still maintaining their original structure. Male whales continue to travel between regions, breeding with different groups, so the populations remain genetically connected, but their cultures diverge at some point.

We still have no idea what the whales are actually saying to each other, and if we ever do work out a way to understand it, we’ll apparently also have to account for regional dialect differences.