Wild birds lead people to honey — and learn from them
The greater honeyguide can recognize distinct vocal signals to help people in Africa locate bee colonies
Peer-Reviewed PublicationIMAGE:
A MALE GREATER HONEYGUIDE ON A BRANCH SEARCHES FOR WAX.
view moreCREDIT: BRIAN WOOD
Key takeaways
- People in parts of Africa communicate with a wild bird, the greater honeyguide, to locate bee colonies and harvest their honey and beeswax.
- A study by UCLA anthropologist Brian Wood and other authors show how this partnership is maintained and varies across cultures.
- They demonstrate the bird’s ability to learn distinct vocal signals traditionally used by different honey-hunting communities.
In parts of Africa, people communicate with a wild bird — the greater honeyguide — in order to locate bee colonies and harvest their stores of honey and beeswax.
It’s a rare example of cooperation between humans and wild animals, and a potential instance of cultural coevolution.
UCLA anthropologist Brian Wood and University of Cape Town ornithologist Claire Spottiswoode were lead authors on a study showing how this valuable partnership is maintained and varies across cultures. Their article, “Culturally determined interspecies communication between humans and honeyguides,” was published in Science.
“Our study demonstrates the bird’s ability to learn distinct vocal signals that are traditionally used by different honey-hunting communities, expanding possibilities for mutually beneficial cooperation with people,” Wood said.
“Honeyguides seem to know the landscape intimately, gathering knowledge about the location of bee nests, which they then share with people, Spottiswoode said. “People are eager for the bird’s help.”
The honeyguides also benefit from locating the colonies: They eat the leftover honeycomb.
The study’s findings build on research published in 2014 that showed the immense benefits of this relationship for the Hadza people. Honeyguides increased Hadza hunter-gatherers’ rate of finding bee nests by 560% and led them to significantly higher-yielding nests than those found without honeyguides. This prior research also found that 8%–10% of the Hadza's yearly diet was acquired with the help of honeyguides.
Spottiswoode and Wood’s study was done in collaboration with the Hadza in Tanzania, with whom Wood has been conducting research since 2004, and the Yao community of northern Mozambique.
Their prior work in both communities documented differences in how each culture attracts honeyguides. Among the Hadza, a honey-hunter announces a desire to partner with the bird by whistling. (Listen to the Hadza vocal signal.)
In Mozambique, Yao honey-hunters do so with a trilled “Brr! ...” followed by a guttural “ ... hmm!” (Listen to the Yao vocal signal.)
Using mathematical models and audio playback experiments, the team studied these signals, their utility to people and their impacts on birds.
They experimentally exposed honeyguides in Tanzania and Mozambique to the same set of prerecorded sounds. This enabled the researchers to test whether honeyguides had learned to recognize and prefer the specialized signals that local honey-hunters used — or were innately attracted to all such signals.
The honeyguides in Tanzania were over three times more likely to cooperate when hearing the calls of local Hadza people than the calls of ‘foreign’ Yao. The honeyguides in Mozambique were almost twice as likely to cooperate when hearing the local Yao call, compared to the ‘foreign’ Hadza whistles.
The study proposes that differences in honeyguide-attracting signals are not arbitrary, but make practical sense. While honey-hunting, both the Hadza and Yao encounter mammals, but only the Hadza hunt them, using bows and arrows. The Hadza’s hunting might explain the less conspicuous whistles they use. Filmed interviews show Hadza hunters explaining that they can evade being detected by their prey because their whistles “sound like birds.”
“Not just among the Hadza, but in hunting cultures around the world, people use whistles as a form of encrypted communication — to share information while avoiding detection by prey,” Wood said.
Conversely, the guttural trill-grunt signal the Yao use to communicate with the honeyguide can help scare off animals they find dangerous.
Although both humans and birds can learn new signals, the authors propose that the mutually beneficial relationship between birds and people spawns local traditions of human-bird communication that remain stable over time.
“The benefits of the honey-hunter-honeyguide relationship should produce long-lasting, ‘sticky’ traditions,” Wood said.
JOURNAL
Science
ARTICLE TITLE
“Culturally determined interspecies communication between humans and honeyguides”
Honeyguide birds learn distinct signals made by honey hunters from different cultures
African honeyguide birds understand and respond to the culturally distinct signals made by local human honey hunters, suggesting cultural coevolution between species, according to a new study. Although the animal kingdom is full of interspecific mutualism, systems in which humans successfully cooperate with wild animals are rare. One such relationship involves the greater honeyguide (Indicator indicator), a small African bird known to lead humans to wild bees’ nests. Humans open the nests to collect honey, and the honeyguides eat the exposed beeswax. Human honey hunters in different parts of Africa often use specialized and culturally distinct calls to signal they are looking for a honeyguide partner and to maintain cooperation while following a guiding bird. For example, honey hunters from the Yao cultural group in northern Mozambique use a loud trill followed by a grunt (“brrr-hm”). In contrast, honey hunters from the Hadza cultural group of northern Tanzania use a melodic whistle. These successful calls have been maintained in these groups for generations. In a series of field experiments across these areas, Claire Spottiswoode and Brian Wood investigated whether honeyguides are more likely to respond to signals of their local human culture than to those of another culture or to arbitrary human sounds. Spottiswoode and Wood discovered that honeyguides in the Yao area were more than three times more likely to initiate a guiding response to the Yao’s distinct call than the Hadza’s whistle. Conversely, honeyguides in the Hadza area were more than three times as likely to respond to the Hadza’s whistle than the Yao’s brrr-hm. According to the authors, the geographic variation and coordination between signal and response observed in this behavioral system suggests cultural coevolution between honeyguides and humans has occurred. In a related Perspective, William Searcy and Stephen Nowicki discuss the study and its findings in greater detail.
For reporters interested in trends, this study builds on previous work published in a July 2016 Report in Science, which demonstrated the reciprocal signaling in honeyguides and honey hunters in Mozambique.
JOURNAL
Science
ARTICLE TITLE
Culturally determined interspecies communication between humans and honeyguides
ARTICLE PUBLICATION DATE
8-Dec-2023
Grunt or whistle: successful honey-hunters know how to communicate with wild honey-seeking birds
AUDIO:
HADZA HONEY-HUNTERS IN TANZANIA COMMUNICATE WITH HONEYGUIDES USING A MELODIC WHISTLE
view moreCREDIT: CLAIRE SPOTTISWOODE
In many parts of Africa, humans cooperate with a species of wax-eating bird called the greater honeyguide, Indicator indicator, which leads them to wild bees’ nests with a chattering call. By using specialised sounds to communicate with each other, both species can significantly increase their chances of accessing calorie-dense honey and beeswax.
Human honey-hunters in different parts of Africa use different calls to communicate with honeyguides. In a new study, researchers have discovered that honeyguide birds in Tanzania and Mozambique discriminate among honey-hunters’ calls, responding much more readily to local than to foreign calls.
“We found that honeyguides prefer the calls given by their local human partners, compared to foreign calls and arbitrary human sounds. This benefits both species, since it helps honey-hunters attract a honeyguide to show them hard-to-find bees’ nests, and helps honeyguides to choose a good partner to help them to get at the wax,” said Dr Claire Spottiswoode, an evolutionary biologist at the University of Cambridge’s Department of Zoology and the University of Cape Town, and joint lead author of the paper.
Hadza honey-hunters in Tanzania communicate with honeyguides using a melodic whistle, whereas Yao honey-hunters in Mozambique use a trill followed by a grunt.
The experiments showed that honeyguides in the Kidero Hills, Tanzania are over three times more likely to cooperate with people giving the local Hadza whistle, than people giving the ‘foreign’ Yao trill and grunt. And the honeyguides in the Niassa Special Reserve, Mozambique are almost twice as likely to cooperate in response to the local Yao trill and grunt, than the ‘foreign’ Hadza whistle.
The phenomenon seems to be self-reinforcing: honeyguides learn to recognise that a specific call indicates a good honey-hunting partner, and humans are more successful in attracting the birds if they use this call.
People who use a different call are less likely to attract a bird to guide them to the honey – so it’s in their interests to stick to the sounds used locally.
“Once these local cultural traditions are established, it pays for everyone – birds and humans – to conform to them, even if the sounds themselves are arbitrary,” said joint lead author Dr Brian Wood, an anthropologist at the University of California, Los Angeles.
The researchers compare this to different human languages, in which the sounds of words are arbitrary, but everyone has agreed on their meaning.
Spottiswoode added: “Just as humans across the world communicate using a range of different local languages, people across Africa communicate with honeyguide birds using a range of different local sounds.”
Like language, these culturally determined calls convey an underlying meaning – signalling a desire to partner with the bird to find honey.
The study is published today in the journal Science.
It is likely that cultural factors relating to the wider hunting practices of different groups have helped to shape the precise design of their honey-hunting calls.
For example, the melodic whistle made by Hadza honey-hunters in Tanzania to attract honeyguide birds sounds like a bird call. This reduces the risk of frightening away the prey animals they’re trying to hunt at the same time.
In contrast, the loud trill followed by a grunt made by Yao honey-hunters in Mozambique, sounds distinctively human. This may be a good way for them to frighten away dangerous large animals like elephants and buffalo.
The findings build on work published in 2016, which found that honeyguide birds in Mozambique respond to the calls of human honey hunters.
The researchers work closely with the Yao and Hadza honey-hunting communities in Africa, whose guidance they have relied on for over a decade.
“It’s such a privilege to witness cooperation between people and honeyguides – these are birds who specifically come to seek us out. The calls really sound like a conversation between the bird and the honey-hunters, as they move together towards a bees’ nest,” said Spottiswoode.
Humans are useful collaborators to honeyguides because of our ability to subdue stinging bees with smoke and chop open the nest, providing wax for the honeyguide and honey for ourselves.
This relationship is a rare example of cooperation between humans and wild animals. Wild honey is a high-energy food that can provide up to 20% of the calorie intake for honey-hunters – and the wax they share or discard is a valuable food for the honeyguide.
“What’s remarkable about the honeyguide-human relationship is that it involves free-living wild animals whose interactions with humans have evolved through natural selection, possibly over the course of hundreds of thousands of years,” said Spottiswoode.
She added: “This ancient, evolved behaviour has then been refined to local cultural traditions – the different human call sounds – through learning.”
The research is a collaboration between researchers at the University of Cambridge, the University of Cape Town, and the University of California Los Angeles, and many honey hunters who inspired and supported the experiments.
Yao honey-hunters in Tanzania use a trill followed by a grunt to communicate with honeyguides
Male honeyguide in Mozambique
In many parts of Africa, humans cooperate with a species of wax-eating bird called the greater honeyguide, Indicator indicator, which leads them to wild bees’ nests with a chattering call.
Yao honey-hunters using fire and tools to harvest a bees' nest in Mozambique
Humans are useful collaborators to honeyguides because of our ability to subdue stinging bees with smoke and chop open the nest, providing wax for the honeyguide and honey for ourselves.
A successful honey hunt in the Niassa Special Reserve, Mozambique
Yao honey-hunters
Honey-hunters Fatima Balasani and Seliano Rucunua call for honeyguides in Niassa Special Reserve, Mozambique
Yao honey-hunter Seliano Rucunua holding male honeyguide
Honeyguide birds in Tanzania and Mozambique discriminate among honey-hunters’ calls, responding much more readily to local than to foreign calls.
CREDIT
Claire Spottiswoode
JOURNAL
Science
METHOD OF RESEARCH
Observational study
SUBJECT OF RESEARCH
Animals
ARTICLE TITLE
Culturally determined interspecies communication between humans and honeyguides
ARTICLE PUBLICATION DATE
8-Dec-2023
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