Whale species that migrate across the globe travel thousands of kilometers each year between cold and tropical waters. However, one population has remained in the same area for so long that it has developed its own unique path. The Arabian humpback whale has become almost unrecognizable. The Wildlife Conservation Society and its Omani partners have shown, in a study published in August 2026 in Frontiers in Marine Science, that the large whales confined to the Arabian Sea form a genetically isolated lineage from other populations. Until now, all these animals belonged to a single family spread across all oceans, without any suspicion of such a divergence. The Arabian humpback whale accumulates genetic differences, a sedentary lifestyle, and a song that no other population shares. Unlike all other humpback whales, those in the Arabian Sea do not migrate. Where their cousins shuttle between polar waters, rich in food, and the tropics, where they reproduce, these sedentary whales remain all year in the warm waters off Oman and India. They find food thanks to the monsoon, which stirs the depths and brings plankton to the surface. To measure this isolation, Rita Amaral's team at the Wildlife Conservation Society compared the DNA of 47 individuals from the Arabian Sea to 2,285 sequences of humpback whales from around the world. The results are clear, as genetic exchanges with other populations are almost non-existent. This group also shows the lowest genetic diversity of all the regions studied, indicating a reduced population that is closed in on itself. This isolation is not recent. By tracing the genetic clock, researchers estimate that the lineage separated from others 43,000 to 113,000 years ago, during the glacial period, when modern humans were just leaving Africa. Since then, these whales have practically no longer mixed their genes with those of the rest of the species. Their most telling signature is heard underwater. The males of the Arabian Sea sing a melody unique to them, shared between the coasts of Oman and India, but nowhere else. In this species, the whale song is transmitted and evolves from one group to another like a trend. Here, cut off from neighbors, it has diverged in its own corner until it became a language of its own. This uniqueness has a price. Today, there are fewer than 100 individuals off Oman, where monitoring is most regular, and their numbers have not increased in twenty years. The population is among the whales most at risk on the planet and is classified as "endangered" on the IUCN Red List. In these very frequented waters, the threats add up. More than two-thirds of the animals examined bear scars left by fishing nets, indicating repeated entanglements. To this are added collisions with ships, the noise of oil platforms, and intense maritime traffic that disrupts their sound exchanges. Recognizing this population officially is therefore not only a taxonomic issue. By naming it Megaptera novaeangliae indic, the fourth recognized lineage of humpback whales, researchers hope to mainly strengthen its protection. A clearly identified subspecies can indeed benefit from more targeted conservation measures in international programs.