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There is an animal behaviour that has become remarkably famous despite possibly not existing. The story is that an African bird called the greater honeyguide summons an animal called a honey badger to help it break into a beehive, and the two share the plunder. Despite decades of reports, including faked footage, we have never had hard evidence that this happens. Many zoologists have dismissed it as a myth. But I wouldn鈥檛 be writing about it if it was as simple as that.
Honeyguides
Let鈥檚 start with what we do know. The greater honeyguide (Indicator indicator) is a songbird that鈥檚 widespread in sub-Saharan Africa. They are mostly black and white, and they eat a lot of insects.
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Greater honeyguides engage in two notable behaviours. The first is brood parasitism: like cuckoos, they lay their eggs in the nests of other birds. They often target little bee-eaters (Merops pusillus), which lay their eggs in underground tunnels. The honeyguide mother punctures any eggs she finds when depositing her own. The chicks are similarly murderous: when one hatches in the darkness of the tunnel it reaches out, and if it finds a surviving little bee-eater chick it will repeatedly bite it,聽.
However, adult greater honeyguides are known for a far more appealing behaviour: guiding humans to bees鈥� nests. A honeyguide will fly close to a person and emit a chattering call, which it doesn鈥檛 use in other circumstances. It then flies away in the direction of a bees鈥� nest, and perches somewhere conspicuous. If the person follows, the bird flies to another perch, and may continue in this way for over a kilometre.
When the pair reach the nest, it鈥檚 the human鈥檚 job to break in. Many hunter-gatherers do this by starting a smoky fire to make the bees sleepy. The human takes the honey; the honeyguide gets juicy larvae and beeswax.
If you aren鈥檛 astonished by this, go back and think about how greater honeyguides reproduce. Because they鈥檙e brood parasites, they never meet their parents, so they can鈥檛 learn from them. The implication is that the guiding behaviour is somehow genetically controlled.
There鈥檚 also the fact they can digest wax at all, which most animals can鈥檛. 鈥淚f you were to eat a candle, you鈥檇 be rather ill,鈥� says Dominic Cram at the University of Cambridge. 鈥淏ut a honeyguide can literally eat a candle.鈥� It鈥檚 been theorised that they have special microbes in their digestive systems to help with this, but for now that鈥檚 just a hypothesis.
According to Cram, Western people first became aware of greater honeyguides when they set up monasteries in Mozambique. 鈥淭he honeyguides would fly in through the window and eat their candles. They would chase them out, and as they鈥檙e chasing this honeyguide away it would lead them to a bees鈥� nest.鈥�
So far, so relatively uncontroversial, if remarkable. But then there鈥檚 the question of whether honeyguides cooperate with animals other than humans.
Honey badgers
Honey badgers (Mellivora capensis), despite their name, are not badgers. They do belong to the same group as badgers, the mustelids, but this group also includes weasels and otters. Like the greater honeyguides, they鈥檙e found throughout much of sub-Saharan Africa, and also in Arabia and Asia. Also known as ratels, they are omnivores, feeding on anything from lizards and rodents to berries and roots. And they also like bee larvae and honey.
Reports that honey badgers are guided to bees鈥� nests by honeyguides date back to at least 1777. In that year, Swedish explorer Anders Sparrman (sometimes spelled 鈥淎ndreas鈥�) published 鈥淎n account of a journey into Africa from the Cape of Good-Hope, and a description of a new species of cuckow鈥�. The 鈥渃uckow鈥� in question is the greater honeyguide, and Sparrman describes the guiding behaviour in detail. He notes that the bird also guides 鈥渁 species of quadruped, which the Dutch name a 鈥楻atel鈥欌��, but gives no evidence and doesn鈥檛 seem to have seen the behaviour himself.
Similar partial accounts have emerged ever since. 鈥淭hese reports don鈥檛 appear to hold an enormous amount of water,鈥� says Cram. Often they鈥檙e second-hand, and they鈥檙e also incomplete: people have seemingly seen part of the interaction, but not the whole thing.
Cram is part of a team that has been studying greater honeyguides for many years. His colleague, Claire Spottiswoode, also at the University of Cambridge, is 鈥渦ndoubtedly the world expert on honeyguides鈥�, he says. They have spent a lot of time in honeyguide territory. 鈥淲e鈥檙e guided extremely regularly, hundreds or even thousands of times between us,鈥� he says. They have never seen honeyguides work with honey badgers 鈥� but it鈥檚 always the first question people ask when they give public talks.
Deciding to dig into the question properly, the researchers compiled every report they could find of honeyguides and honey badgers interacting. 鈥淭here is pretty poor-quality evidence,鈥� says Cram. 鈥淚t鈥檚 very patchy.鈥� The animals鈥� ranges do overlap, as do the periods when they鈥檙e active, and people have seen them together at bees鈥� nests. But there were no good accounts of honeyguides calling to honey badgers, or of honey badgers following honeyguides.
鈥淲ere it to just be a survey only of the literature, we would probably have concluded that the most likely outcome is that this doesn鈥檛 happen,鈥� says Cram.
Indigenous expertise
However, they didn鈥檛 stop there. They also asked the people best placed to know: Indigenous honey hunters. This project was spearheaded by Jessica van der Wal at the University of Cape Town in South Africa, who has built up a network of honey-hunting communities across Africa. She has interviewed 400 honey-hunters from 11 communities in nine countries.
Just 76 interviewees said they had seen honeyguides and honey badgers interact, and 111 said they believed the two cooperate. That鈥檚 a minority of the total. However, about two-thirds of the people who responded positively came from three communities in Tanzania: the Hadzabe, Maasai and a mixed-culture community in the south. The Tanzanian honey hunters were very likely to say they had seen the interaction or believed it existed. Honey hunters elsewhere said the opposite. 鈥淎cross most of those communities, it was very rare to have seen the two [animals interacting] and most people didn鈥檛 believe in it either,鈥� says Cram.
One possible explanation is that the behaviour is actually widespread, but for some reason the Tanzanian peoples are more likely to have seen it. That makes sense for one Tanzanian group, the Hadzabe, as they are hunter-gatherers who often move stealthily through the bush, and therefore might not disturb the honey badgers or the honeyguides. However, another Tanzanian group, the Maasai, are pastoralists that spend a lot of time noisily driving cattle, yet they also report seeing the same behaviour.
鈥淏ased on that, we tentatively ruled out the idea that it occurs everywhere but is difficult to see,鈥� says Cram. 鈥淲e think it鈥檚 probably more likely that it is indeed restricted to Tanzania and that鈥檚 why those three communities had seen it at much higher rates than communities elsewhere.鈥� The findings were聽聽in the聽Journal of Zoology.
Actually observing the behaviour is going to be tricky. If a human approaches, the honey badger is likely to flee, because many human groups in Africa hunt or otherwise persecute them, so they have learned to be wary of us. At that point, the honeyguide will turn its attention to the person.
The team suggests putting GPS collars onto honey badgers, which would allow them to be tracked as they followed honeyguides 鈥� or as they responded to speakers playing recorded honeyguide calls. 鈥淭hose experiments are going to be very challenging,鈥� says Cram.
If the behaviour does exist, it is ecologically important. Last year the team published a study showing that聽, so anytime a bees鈥� nest gets broken open it releases a substantial flow of nutrients.
Cram adds that the question is still unresolved. 鈥淲e don鈥檛 give a definitive answer here,鈥� he says. 鈥淚t is possible that [the honey hunters] are mistaken. However, the strength of evidence here, the near-universal belief in it in some communities and the high rates of observations of it in those communities, should certainly be taken into account.鈥�
For Cram, the study also shows the value of working closely alongside Indigenous people and valuing their expertise. He points out that the evidence supplied by Western scientists to date led the team to think the behaviour didn鈥檛 exist, and it was the Indigenous honey hunters鈥� testimony that swayed them. 鈥淭hat鈥檚 how strongly this can swing the needle,鈥� he says. 鈥淚t was long overdue.鈥�
