Cultural hitchhiking: How social behavior can affect genetic makeup in dolphins

March 18, 2014

A UNSW-led team of researchers studying bottlenose dolphins that use sponges as tools has shown that social behaviour can shape the genetic makeup of an animal population in the wild.

Some of the dolphins in Shark Bay in Western Australia put conical marine sponges on their rostrums (beaks) when they forage on the sea floor - a non-genetic skill that calves apparently learn from their mother.

Lead author, Dr Anna Kopps, says sponging dolphins end up with some genetic similarities because the calves also inherit DNA from their mothers. As well, it is likely that sponging dolphins are descendants of a "sponging Eve", a female dolphin that first developed the innovation.

"Our research shows that social learning should be considered as a possible factor that shapes the genetic structure of a wild animal population," says Dr Kopps.

"It is one of the first studies to show this effect - which is called cultural hitchhiking - in animals other than people."

The study is published in the journal Proceedings of the Royal Society B.

Dr Kopps and her colleagues identified individual dolphins in western Shark Bay about 850 kilometres north of Perth. They observed them from a boat as they foraged for food, travelled around the bay, rested, and played with other dolphins.

Genetic samples were also taken, and analysed for mitochondrial DNA type, which is only inherited from the mother.

It was found that the dolphins that lived in shallow waters, where sponges do not grow, mainly fell into a genetic group called Haplotype H.

The dolphins living in deep waters, where sponges do grow, were predominantly Haplotype E or Haplotype F.

"This striking geographic distribution of a genetic sequence cannot be explained by chance," says Dr Kopps, who carried out the research while at UNSW and is now at the University of Groningen.

As well, the DNA results from 22 dolphins that both lived in deep water and used sponges as tools showed they were all Haplotype E.

"For humans we have known for a long time that culture is an important factor in shaping our genetics. Now we have shown for the first time that a socially transmitted behaviour like tool use can also lead to different genetic characteristics within a single animal population, depending on which habitat they live in" she says.
-end-
The team includes UNSW's Professor Bill Sherwin and researchers from the University of Zurich and Murdoch University.

Media Contacts:

Dr Anna Kopps (in the Netherlands): +31 50 363 2075, anna.kopps@gmx.com

Professor Bill Sherwin: + 61 (2) 9385 2119, w.sherwin@unsw.edu.au

UNSW Science media: Deborah Smith, + 61 (2) 9385 7307, + 61 (0) 478 492 060, deborah.smith@unsw.edu.au

University of New South Wales

Related Dolphins Articles from Brightsurf:

Study finds high levels of toxic pollutants in stranded dolphins and whales
Researchers examined toxins in tissue concentrations and pathology data from 83 stranded dolphins and whales from 2012 to 2018.

Tracking humanity's latest toxins in stranded whales and dolphins
As humanity develops new types of plastics and chemicals, researchers are constantly trying to keep up with understanding how these contaminants affect the environment and wildlife.

Young dolphins pick their friends wisely
Strategic networking is key to career success, and not just for humans.

Dolphins learn foraging skills from peers
Dolphins can learn new skills from their fellow dolphins. That's the conclusion of a new study reported in the journal Current Biology on June 25.

Dolphins learn in similar ways to great apes
Dolphins learn new foraging techniques not just from their mothers, but also from their peers, a study by the University of Zurich has found.

Shelling out for dinner -- Dolphins learn foraging skills from peers
Dolphins use empty gastropod shells to trap prey. A new study demonstrates for the first time that dolphins can learn this foraging technique outside the mother-calf bond - showing that they have a similar cultural nature to great apes.

Good night? Satellite data uncovers dolphins on the move at nighttime
More than 1,000 bottlenose dolphins live in Florida's Indian River Lagoon year-round.

Cooperative male dolphins match the tempo of each other's calls
When it comes to working together, male dolphins coordinate their behavior just like us.

Dolphins gather in female family groups
Social clusters including mothers' groups play an important role in the life of southern Australian bottlenose dolphins, a new study shows.

Lights on fishing nets save turtles and dolphins
Placing lights on fishing nets reduces the chances of sea turtles and dolphins being caught by accident, new research shows.

Read More: Dolphins News and Dolphins Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.