CRITTER CHATTER
Talking duck tape discovered, plus marmoset conversations
TALKING DUCK
New research published in the journal Philosophical Transactions of the Royal Society B documents the first ever scientific evidence of a talking duck. The duck, a male musk duck named ‘Ripper’, hand-reared in captivity at the Tidbinbilla Nature Reserve near Canberra, Australia, was recorded saying the phrase “you bloody fool” repeatedly. In the recordings, made 30 years ago by retired researcher Dr Peter Fulgar, Ripper can also be heard imitating the sound of a door slamming.
Dr Fulgar’s recordings resurfaced recently after Professor Carel ten Cate of Leiden University came across a brief mention of them in a book on bird vocalisations and followed the reference up. Initially believing it was a hoax, he was convinced after hearing the recordings. He also unearthed Dr Fulgar’s recordings of a second Tidbinbilla musk duck imitating the call of another duck species. While further investigation didn’t turn up any more talking ducks, ten Cate did find evidence of a musk duck at Pensthorpe Natural Park in the UK that had been heard imitating the sounds of “coughing, and a snorting pony” and one at Slimbridge Wildfowl Trust, also in the UK, that could replicate its keeper’s cough and the squeak of a turnstile. This is the first time mimicry has been confirmed in a duck species, although
some songbirds, crows, parrots and hummingbirds also do it. The rather creepy recording of Ripper speaking can be found on YouTube https://www.youtube. com/watch?v=46RSYCXwSXo. Irishexaminer.com, 7 Sept 2021.
EAVESDROPPING MARMOSETS
The forests of north-eastern Brazil are home to the common marmoset ( Callithrix jacchus). Like squirrels, they spend a good deal of their time in trees, and are similar in size. They have a sophisticated social structure with extended families of up to 15 marmosets living, eating, and hanging out together. However, while there are only one or two breeding pairs within each group, it seems that when the babies are born the whole clan take turns in caring for the youngsters. Because marmosets rely on others for help, they have to evaluate who will (or won’t) be reliable in terms of cooperation and mutual support. New research by Judith Burkart and Rahel Brügger, evolutionary anthropologists at the University of Zurich, demonstrates the miniature primates will eavesdrop on the conversations of other marmosets in order to assess them based on what they are “saying”. Essentially, they prefer to mingle with those they feel will make the best nannies for their young.
Burkart and Brügger placed a single marmoset in a room and played it recordings of marmoset vocalisations from a hidden speaker. The chatter might be that of a positive interaction, an infant calling for food and an adult responding gently, for example; or it might be a negative one, with the adult reacting aggressively to the hungry baby. As a control, the scientists only played back recordings from a single animal.
They then focused an infrared camera on the faces of the marmosets, to record the temperature of their noses: a drop in nasal temperature would indicate that the marmoset was alert and engaged. Initial findings indicated that the animals became aroused during the combined calls but not during the individual vocalisations, which told the researchers they were reacting to “conversations”.
Next, the scientists let the marmosets into an adjoining room containing toys and a mirror. Since they don’t recognise their own reflections, marmosets are likely to approach a mirror and socialise with the image. The experiment was arranged so that the animals would assume the calls that they’d just heard were coming from the individual reflected in the mirror. After hearing a positive interaction played back, the marmosets readily entered the room and ran up to the mirror, ready to socialise with the stranger – but after the negative, uncooperative vocalisations, the marmosets were hesitant to approach the reflection: they preferred interacting with a “stranger” who was cooperative, which indicates that they aren’t just passive observers, but make decisions about others based on what they hear – just as humans do. The team plan to build on their success and use temperature-mapping to investigate bigger questions, such as the primate origin of human traits like morality. sciencemag. org, 3 Feb 2021.