Evolutionary biologists have revealed for the first time the genetic history of a famous killer whale and its group that historically collaborated with whale hunters off the New South Wales coast. The leader of the pod, known as "Old Tom" and famous for helping whalers hunt baleen whales in the 20th century, is genetically linked to New Zealand's current killer whales, new DNA research has found.
Old Tom also shared a common ancestor with killer whales in Oceania, the North Pacific, and the North Atlantic, but was most similar to modern New Zealand killer whales. However, much of Tom's DNA code is not found in other killer whales around the world, suggesting that Eden's killer whales may have become locally extinct.
Image depicting the ancestor of the killer whale "Old Tom", who was at the heart of the cooperative hunting relationship between killer whales and human whalers. Source: Isabella Reeves, Flinders University
"Old Tom" and his family, known as the Eden killers, would help whalers hunt down targets and be rewarded with lips and tongues from whale carcasses. This is the famous "law of the tongue".
This legendary relationship between the whalers and Old Tom's family lives on and has created a strong bond between whalers for many generations. Old Tom is 6.7 meters long and weighs 6 tons. After being washed ashore in 1930, he is now on display at the Eden Killer Whale Museum.
Led by Flinders University and Cetacean Research Center doctoral student Isabella Reeves, a global team of researchers worked with Old Tom on an ambitious journey, relying on ancient DNA technology, in an attempt to trace Old Tom's genetic ancestry by sequencing DNA and comparing his DNA to killer whales around the world.
Working with Thaua traditional custodian Steven Holmes, the researchers also revealed new insights in an attempt to decolonize the history of the Eden killers, which has never been formally recorded before.
Reeves' discovery and Aboriginal connection
Lead researcher Isabella Reeves said that while the genetic comparison did not reveal any direct descendants of Old Tom, the researchers did find that Tom shared most of his DNA variation with other killer whales, suggesting that they are now extinct locally.
Eden killer whales represent a rare partnership between humans and whales. Tracing Old Tom's genetic ancestry is an exciting journey to provide the first glimpse into the genetic history of a group that has captured the hearts of the community and whale enthusiasts alike.
"Our research has also lifted the veil on decolonization history and entered uncharted territory. Our work with a Traditional Custodian has given us a new perspective on Eden's whaling history, correcting historical inaccuracies and revealing an important aspect of this unique story, namely the bond between their people and these whales. Importantly, we want to ensure this aspect of the story is recognized in the future."
In Liangzhe Bay, the coastal Tahua people (part of the Yuin nation) legend have established a connection with the killer whales through dreams, and since the Tahua people rely on the ocean for resources, this relationship is highly respected and relied upon.
"We must recognize that Australia's Aboriginal people had relationships with killer whales before European colonization and the advent of local commercial whaling," Ms Reeves said. "This study corrects discrepancies in local records and provides new insights into the origins of Eden's killer whales and the history of killer whales in Australasia."
Traditional custodian Steven Holmes said the Tawa people had a long-standing friendship with Eden's whales, especially Old Tom.
"We considered the killer whales to be our brothers. Our Dreamtime stories connected us to the killer whales, who were reincarnated as killer whales when the Tawa died. They would help the whalers by herding other whales in Turembulerrer Bay (Two Fold Bay) for the whalers to kill. The indigenous whalers would reward the killer whales with the tongues of the dead whales. This soon became known as the 'tongue method.'"
Compiled from: ScitechDaily