54 Scientific American, September 2019DOMESTICATED LIARS
EVEN AT OUR very own home and hearth, animals may
deceive. Dogs are lauded for their supreme loyalty, yet
the real picture is more complicated. Working with
domestic dogs, ethologist Marianne Heberlein of the
University of Zurich arranged for the dogs to interact
with one of two women who either shared food with
them (call her Ms. Cooperator) or failed to share and
took the food herself (Ms. Competitor). The dogs
could then lead these partners to a favored food, a
nonfavored food or a location with no food. On day
one, the dogs led Ms. Cooperator more often to the
location with the preferred food. By day two, the dogs
had acquired more knowledge about their situation.
Now they led Ms. Competitor less often to the pre-
ferred-food location and inhibited their searching be-
havior toward the preferred food in her presence.
As anyone who has lived with dogs knows, they
are not great at forgoing beloved foods. Apparently
the dogs in this experiment wanted to increase
their chances of getting the desirable food later—
and knew that deceiving the selfish Ms. Competitor
might just increase their odds. Maybe, too, He-
berlein says, they just did not fancy the notion of a
disliked human getting a treat. Whatever their mo-
tivation, the dogs’ deception was tactical.
What is the take-home lesson here? Be nice to
dogs, and naturally, they will be nice to you. More
broadly, animal duplicity may be carried out with
awareness and sometimes even with emotional gus-
to. For this reason, we may see something of our-
selves in the dogs or in cuttlefish who give off false
signals in mating and birds who mislead to steal food.
And yet across species—including those animals who
deceive in the absence of premedi tated in tent—the
same individuals may act hon estly in some cir-
cumstances and connivingly in others. That Janus-
headed nature may sound familiar to us, too.
MORE TO EXPLORE
“False Orgasm” in Female Brown Trout: Trick or Treat?
Erik Petersson and Torbjörn Järvi in Animal Behaviour, Vol. 61, No. 2,
pages 497–501; February 2001.
It Pays to Cheat: Tactical Deception in a Cephalopod Social
Signalling System. Culum Brown et al. in Biology Letters, Vol. 8,
No. 5, pages 729–732; October 23, 2012.
Deception by Flexible Alarm Mimicry in an African Bird. To m P.
Flower et al. in Science, Vol. 3 4 4, pages 513–516; May 2, 2014.
Chimpanzees Strategically Manipulate What Others Can See.
Katja Karg et al. in Animal Cognition, Vol. 18, No. 5, pages 1069–1076;
September 2015.
Deceptive-like Behaviour in Dogs (Canis familiaris). Marianne T. E.
Heberlein et al. in Animal Cognition, Vol. 20, No. 3, pages 511–520;
May 2017.
Drosophila melanogaster Cloak Their Eggs with Pheromones,
Which Prevents Cannibalism. Sunitha Narasimha et al. in PLOS
Biology, Vol. 17, No. 1, Article No. e2006012; January 10, 2019.
FROM OUR ARCHIVES
The Orca’s Sorrow. Barbara J. King; March 2019.
scientificamerican.com/magazine/saWHY
WE
TRUST
LIES
THE MOST EFFECTIVE MISINFORMATION
STARTS WITH SEEDS OF TRUTHBy Cailin O’Connor and James Owen Weatherall
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