A new study has found that dolphins whistle to each other as part of a male bonding ritual and rely on “wingmen” to vie for potential mates’ affection.
Experts from the University of Bristol say that bottlenose dolphins could become more popular simply through vocal exchanges helping them maintain weaker but vital social relationships.
Not only that, but a separate study using the same data showed that the more popular a dolphin is with other males, the more successful it is in producing calves.
This study was led by the University of Zurich.
Groups of male bottlenose dolphins have been found to work together to compete with rival groups for access to females, with the most popular males in the group having the most mating success.
A new study has found that dolphins whistle to each other as part of a male bonding ritual and rely on “wingmen” to vie for potential mates’ affection.
A Bristol study found that male dolphins can stay popular by using high pitched voices (pictured) with other males as an inexpensive way to keep their alliances going.
How do dolphins use their signature whistles?
Signature whistles are sounds made by dolphins that are used to identify different individuals.
Baby dolphins eventually make their own individual whistle, but in the early stages of life they use their mother’s whistle.
In a previous study, researchers observed a mother dolphin at Six Flags Discovery Kingdom in California who gave birth to a baby dolphin named Mira in 2014.
They recorded 80 hours of sounds from mother, calf and other dolphins in the enclosure during two months before birth and two months after birth.
Recordings showed that the mother dolphin began to increase her signature whistle two weeks before birth and continued to do so for two weeks after birth before subsiding.
On the contrary, the other dolphins in the enclosure at that time did not emit their characteristic whistle at a very high speed.
The Bristol study, meanwhile, found that male dolphins can stay popular by using high-pitched voice messages with other males as an inexpensive way to maintain their alliances, rather than through other physical activities.
Experts say this is an important interaction that needs to be maintained as groups grow larger and competition for resources intensifies.
Lead author Emma Chereskin, a student at the University of Bristol, said: “Many animals, including humans, use tactile contact to strengthen and validate important relationships.
“But as the number of intimate social relationships increases, so does the need for time and space available to maintain relationships through physical contact.
“Male bottlenose dolphins form strategic multi-level alliances, and we wanted to know how they maintain multiple alliances in large groups.”
While male dolphins are known to use physical contact, such as gentle petting, to bond with strongly bonded allies, research from the University of Bristol shows that they rely on less labor-intensive voice exchanges to stay in touch with weaker allies.
The scientists used nine years of acoustic and behavioral data from a population of dolphins in Shark Bay, Western Australia, which helped them evaluate how male dolphins bond with each other.
Bottlenose dolphins band together to hunt or defend themselves against predators. Adult males live mostly alone or in groups of two or three and join packs for short periods of time.
They typically have between 10 and 30 members, although “superpods” of over 1,000 have been recorded.
Senior author, Dr Stephanie King, also from Bristol, said: “We found that in major dolphin alliances, strongly bonded allies engage in more partner contact behaviors such as petting and rubbing, while loosely bonded allies engage in more exchanges. whistles.
“It shows that these weaker but still important social relationships can be maintained through voice exchange.”
Scientists used nine years of acoustic and behavioral data from a population of dolphins in Shark Bay, Western Australia, to help them assess how male dolphins bond with each other.
Male dolphins in Shark Bay, Western Australia live in complex social groups in which they form long-term bonds to cooperate with other males.
This confirms British anthropologist Professor Robin Dunbar’s theory that vocalization and language have evolved to replace grooming.
Increasing group sizes placed unbearable demands on the time available for physical contact.
Ms Chereskin said: “Our results provide new evidence that voice exchange can serve as a convergence function.
“But more importantly, and consistent with the social bonding hypothesis, voice exchange could function as a substitute for physical communication, allowing male dolphin allies to “communicate at a distance.”
“This evidence in support of the social bonding hypothesis beyond the lineage of primates raises exciting new questions about the origin and evolution of language across taxa.”
Male dolphins in Shark Bay, Western Australia live in complex social groups in which they form long-term bonds to cooperate with other males.
To do this, they unite in large stable unions.
Within these unions, males form smaller and less stable groups of two or three to mate with females, steal them from other unions, or defend themselves against attacks, according to researchers from the University of Zurich.
Within these unions, males form smaller and less stable groups of two or three to mate with females, steal them from other unions, or defend themselves against attacks, according to researchers from the University of Zurich.
“This kind of cooperation between males for the purpose of reproduction is very unusual in the animal kingdom,” said Livia Gerber, a former PhD student in the Department of Anthropology at the University of Zurich.
“It has only been observed in a much less complex form in some other primates.”
Together with an international team led by UZH professor Michael Krützen, she wanted to find out whether the complex social life of dolphins affected the reproductive success of males, or, like most other species, stronger or more experienced males are more likely to produce offspring. offspring.
The researchers analyzed behavioral data from 85 male dolphins over 30 years and used the genetic data to analyze the paternity of more than 400 dolphins.
The study found that well-integrated “popular” males with strong social bonds with many alliance partners produce the most offspring.
Gerber said: “Well-integrated men may be in a better position to take advantage of collaboration and gain access to critical resources like food or partners.”
“They may also be more resilient to mate loss compared to those with few but more intimate partners.”
Bottlenose dolphins inhabit warm and temperate seas around the world and can be found everywhere except the Arctic and Antarctic.
They are known for their intelligence, use sea sponges as tools to obtain food that would normally be unavailable, and communicate through pulsing sounds, clicks, and body language.
Both studies were published in the journal Current Biology.
WHY SCIENTISTS THINK WHALES AND DOLPHINS ARE GRIEF
Whales and dolphins have been seen on several occasions “carrying” or caring for their dead young.
These creatures may have been in mourning, or they may not have accepted or acknowledged that the offspring or companion had died.
Scientists still don’t know if aquatic mammals actually recognize death, and plan to do more research on the subject.
In 2016, scientists found evidence that whales and dolphins are “watchful” of their dead.
They analyzed several cases when mammals clung to the bodies of dead compatriots and were on duty over a dead comrade.
At the time, they said mourning was the most likely explanation.
The study collected observations of 14 events.
They found that mothers often carried their dead babies over the water, often accompanied by friends.
In many cases, the dead offspring decomposed, indicating that they had been kept for a long time.