Male bottlenose dolphins create the biggest known multi-level alliance network outside of humans, according to an international team lead by University of Bristol academics.

These cooperative group ties boost male access to a disputed resource.

Male dolphins forming an alliance
dolphins
(Photo : TJ Fitzsimmons/Unsplash)

The researchers examined association and consortship data from 121 adult male Indo-Pacific bottlenose dolphins in Shark Bay in Western Australia, along with colleagues from the University of Zurich and the University of Massachusetts.

Their findings were published in the Proceedings of the National Academy of Sciences today (PNAS), as per ScienceDaily.

Male dolphins in Shark Bay establish first-order coalitions of two to three males to pursue consortships with individual females jointly.

Second-order coalitions of four to fourteen unrelated males fight with other alliances for female dolphin access, whereas third-order alliances form amongst collaborating second-order alliances.

Cooperation between friends is prevalent in human civilizations, according to co-lead author Dr. Stephanie King, Associate Professor at Bristol's School of biological sciences.

Their ability to form strategic, cooperative ties at numerous social levels, such as national and international commerce or military alliances, was formerly considered to be unique to our species.

Not only have scientists demonstrated that male bottlenose dolphins form the largest known multilevel alliance network outside of humans, but they have also demonstrated that cooperative relationships among groups, instead of simply coalition size, allow males to devote more time to females, increasing their reproductive success.

According to Dr. Simon Allen, Senior Lecturer at Bristol's School of Biological Sciences, who contributed to the study, the findings show that the duration for which these teams of male dolphins consort females is dependent on being well-connected with third-order allies, that is, social ties between alliances lead to long-term benefits for these males.

Intergroup cooperation in humans was assumed to be unique and dependent on two additional characteristics that separate humans from our common ancestor with chimps: the emergence of pair bonds and male parental care.

The findings, however, show that intergroup alliances can emerge without these characteristics from a more chimp-like social and mating system, according to Richard Connor, Professor Emeritus at the University of Massachusetts and now affiliated with Florida International University, who co-led the study with Dr. King.

Professor Dr. Michael Krützen, one of the study's authors and the Head of the Anthropology Institute at the University of Zurich, added, "It is unusual for non-primate studies to be conducted from an anthropology department, but our study shows that important insights into the evolution of character traits previously thought to be uniquely human can be gained by examining other highly social, large-brained taxa."

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Mating Dolphins

Some people may be surprised to find that wild dolphin populations throughout the world are gradually declining, as per Study.

Climate change, in conjunction with anthropogenic activity, is causing habitat degradation and endangering dolphin species.

Dolphin reproduction, also known as dolphin mating, is the complicated process through which new offspring or individuals are produced. Dolphins only have one calf every three to five years.

The sea mammals are members of the Cetaceans marine mammal group or order. Cetaceans include not just dolphins but also whales and porpoises.

Cetacean mating occurs when dolphins, whales, and porpoises form pods to generate new individuals.

Although the pod size fluctuates when it comes time to mate, marine animals do share several morphological similarities.

Dolphins, whales, and porpoises all have blubber-covered bodies. Blubber is a sort of animal fat that adds to the Cetaceans' fusiform-shaped bodies.

Almost all Cetaceans have a dorsal fin on the top of their bodies that helps to stabilize them while they move.

Cetaceans have a huge brain, which experts attribute to their complex behavioral and social systems. Cetaceans have a spiracle or blowhole at the top of their heads that allows them to breathe air.

They are also warm-blooded animals that can change their body temperatures to survive on all of the world's seas. Finally, they all give birth to live offspring or calves by internal reproduction.

Dolphin sexual selection is very competitive and aggressive since they have more than one probable partner. Sexual selection is the process of choosing a mate with whom to have children.

Male dolphins begin the sexual courting with vocalizations and elaborate swimming patterns, but their physical traits, such as body size and behavioral dominance, are frequently what attract females.

Male dolphins will also try to attract a female's attention by giving her a gift.

They will also battle other male dolphins in the area, which involves raking each other with their teeth.

Raking is when they scrape their teeth along with another's body, which is done with enough force to leave distinctive scars.

Scientists have also observed female dolphin pods driving away males until they are ready to mate.

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