BWB – Science still debates

Common dolphins are actually the most abundant dolphin species in the world, with about six million individuals across all oceans. Since the 1990s, there have been two recognised species: short- and long-beaked common dolphins (Delphinus delphis and Delphinus capensis). However, research in the early 2010s discovered that long-beaked common dolphins around the world aren’t closely related to each other, but instead evolved independently from short-beaked common dolphins. The length of their beak changed in different areas of the world due to their environment (a process known as convergent evolution). So scientists are still debating whether they are two different species or the same species with different ecotypes.

Short-beaked common dolphins prefer subtropical and temperate waters and are primarily offshore in large pods. Long-beaked common dolphins are found in smaller pods and have more teeth, which are adapted to a wider variety of coastal prey. They are also more localised, occurring in coastal regions such as West Africa, California, and Peru. Their hourglass pattern is often less distinct. An interesting fact: the long-beaked common dolphin has one of the highest tooth counts among toothed whales, with around 230 teeth that are conical in shape.

By Eva Köhle