By Dr. Becker
Humans are one of only a few species who can learn to imitate new sounds, thus communicating socially with others, including other species. This ability for vocal learning is a key foundation of language development.
Most animals use sounds to communicate, but they are born with the knowledge of how to use them; it’s not a learned concept, per se. Killer whales, however, are an exception. New research suggests they’re not only capable of vocal learning but also of socializing with other species, including bottlenose dolphins.
Killer Whales Learn to Communicate with Dolphins
When killer whales are socialized with bottlenose dolphins, something extraordinary happens: their usual clicks, whistles, and pulsed calls shift to more closely mimic those of the dolphins. While it’s known that whales who live together often communicate in different dialects, there’s been debate over whether these dialects were truly learned (versus innate).
The new study suggests killer whales do, indeed engage in vocal production learning and also are capable of contextual learning.1 As reported by Science Daily:2
“All three killer whales that had been housed with dolphins for several years shifted the proportions of different call types in their repertoire to more closely match the distribution found in dolphins – they produced more clicks and whistles and fewer pulsed calls.
The researchers also found evidence that killer whales can learn completely new sounds: one killer whale that was living with dolphins at the time of the experiment learned to produce a chirp sequence that human caretakers had taught to her dolphin pool-mates before she was introduced to them.
Vocal learning skills alone don't necessarily mean that killer whales have language in the same way that humans do. However, they do indicate a high level of neural plasticity, the ability to change circuits in the brain to incorporate new information.”
Killer Whales Are Highly Intelligent
Perhaps it’s not so surprising that a killer whale would learn to socialize with bottlenose dolphins, particularly if they’re raised in a captive situation. Killer whales, or orcas, have the second-largest brains of all marine mammals. Their brains can weigh up to 15 pounds, which in and of itself isn’t overly remarkable considering killer whales’ size.
However, when brain-weight-to-body-weight-ratios, which are used as a measure of intelligence, are factored in, killer whale brains are 2.5 times the average, which is similar to that of chimpanzees (for comparison, humans are seven times the average).3 There are other indications that killer whales are highly intelligent as well, including:4
- They have a “culture,” which includes learning from others and teaching difficult hunting techniques to offspring; they also live among extended family including grandparents and calves
- Learning local and complex languages that are retained for many generations
- Using bio-sonar, or echolocation, to find fish in murky water and even single out their favorite food, Chinook salmon
It’s because of this undeniable intelligence that holding killer whales in captivity has come under such intense scrutiny in recent years. Of note, there are no records of a killer whale harming a human in the wild, but several “attacks” against humans – some fatal – have occurred among killer whales in captivity.
It’s quite possible the captive situation stresses the animal and/or angers it to the point that it lashes out. Neuroscientist Lori Marino, part of the Neuroscience and Behavioral Biology Program at Emory University in Atlanta, told Phys.org:5
“…certainly, if we are talking about whether killer whales have the wherewithal and the cognitive capacity to intentionally strike out at someone, or to be angry, or to really know what they are doing, I would have to say the answer is yes… Living in a tank and having to splash people with your tail every day for 27 years would make anyone go nuts.”
Dolphins and Whales Are Closely Related
Another reason why it makes perfect sense that a killer whale might choose to communicate with a dolphin is this: dolphins are a type of whale. The name “whale” actually identifies several different types of marine mammals, including whales, dolphins, and porpoises.
All are known as cetaceans, but dolphins and porpoises belong to the toothed whale group. Killer whales, in turn, are actually dolphins, the largest variety known. They’re fascinating for quite a number of reasons:6
- Killer whales are very protective of their young, who are cared for not only by their mother but also by other adolescent females in the pod
- They’re often compared to wolves, as they hunt cooperatively, have complex social relationships and are top predators
- The shape and size of a killer whale’s dorsal fin, along with the unique saddle patches behind the dorsal fin, can be used to distinguish one from another
- Killer whales can live to be 50 to 80 years old and have no natural predators
Further, as noted by PBS:7
“Orca intelligence isn’t unexpected given that it is a highly social animal that hunts in coordinated packs. Some of the smartest animals in the world–chimps, elephants, dogs, humans – are also highly social.
As a result of their intelligence and sociability, killer whale pods have developed novel hunting strategies that are handed down through multiple generations. The techniques vary from region to region depending on available food items, but they are all are a testament to the killer whale’s keen predatory intelligence and ingenuity.”
For instance, a group of killer whales will charge an ice float, creating a huge wave, then diving under and “pushing” the wave further with their tails. The wave knocks seals right off the ice, making them easy prey. Killer whales are also known to purposely beach themselves while they grab sea lions and elephant seals right from the shore. They then hop and “flap” their way back into the water.
Killer whales will even take on sharks, which they push to the surface of the water then hit over the head with their tails. Next, they flip the shark over, which paralyzes it, and makes it an incredibly easy meal. The video below shows a group of killer whales “catching” a shark.
When you see their cooperative and calculated movements, it’s clear these creatures have intelligence likely far beyond what is currently known.