
-
Israel says expands Gaza offensive to seize 'large areas'
-
Curry drops 52 as Warriors win, Jokic bags career-high 61 in Denver loss
-
South Korea mobilising 'all resources' for violence-free Yoon verdict
-
Myanmar quake victim rescued after 5 days as aid calls grow
-
Real Madrid coach Ancelotti tax fraud trial set to begin
-
Warner showcases 'Superman' reboot, new DiCaprio film
-
'Incredible' Curry scores 52 as Warriors down Grizzlies, Bucks edge Suns
-
Asian markets edge up but uncertainty rules ahead of Trump tariffs
-
Nintendo's megahit Switch console: what to know
-
Nintendo to unveil upgrade to best-selling Switch console
-
China practises hitting key ports, energy sites in Taiwan drills
-
Oil, sand and speed: Saudi gearheads take on towering dunes
-
All eyes on Tsunoda at Japan GP after ruthless Red Bull move
-
'Image whisperers' bring vision to the blind at Red Cross museum
-
Hay shines as New Zealand make 292-8 in Pakistan ODI
-
Other governments 'weaponising' Trump language to attack NGOs: rights groups
-
UK imposes online entry permit on European visitors
-
How a Brazilian chief is staving off Amazon destruction
-
Meme politics: White House embraces aggressive alt-right online culture
-
China launches military drills in Taiwan Strait
-
US senator smashes record with 25-hour anti-Trump speech
-
Brazil binman finds newborn baby on garbage route
-
US senator smashes record with marathon anti-Trump speech
-
Trump advisor Waltz faces new pressure over Gmail usage
-
Niger junta frees ministers of overthrown government
-
Trump set to unleash 'Liberation Day' tariffs
-
Boeing chief to acknowledge 'serious missteps' at US Senate hearing
-
Real Madrid hold Real Sociedad in eight-goal thriller to reach Copa del Rey final
-
Nuno salutes 'special' Elanga after stunning strike fires Forest
-
PSG survive scare against Dunkerque to reach French Cup final
-
Sundowns edge Esperance as crowd violence mars quarter-final
-
Nottingham Forest beat Man Utd, Saka scores on Arsenal return
-
Elanga wonder-goal sinks Man Utd as Forest eye Champions League berth
-
Stock markets mostly advance ahead of Trump tariffs deadline
-
US movie theaters urge 45-day 'baseline' before films hit streaming
-
Saka scores on return as Arsenal beat Fulham
-
Third-division Bielefeld shock holders Leverkusen in German Cup
-
Ball-blasting 'Torpedo bats' making waves across MLB opening weekend
-
Newsmax shares surge more than 2,000% in days after IPO
-
Thousands of Hungarians protest against Pride ban law
-
GM leads first quarter US auto sales as tariffs loom
-
Tesla sales tumble in Europe in the first quarter
-
No 'eye for an eye' approach to US tariffs: Mexico
-
NFL club owners back dynamic kickoffs, delay tush push vote
-
Trump 'perfecting' new tariffs as nervous world braces
-
Trump nominee says to press UK on Israel arms
-
French court says Le Pen appeal ruling could come before presidential vote
-
The battle to control assets behind Bosnia crisis
-
Prabhsimran powers Punjab to IPL win over Lucknow
-
Mass layoffs targeting 10,000 jobs hit US health agencies

Wild birds analyze grunts, whistles made by human honey-hunters
In parts of Africa, expert honey-hunters call out to a species of bird known as the greater honeyguide, which leads them to wild bee nests -- a mutually beneficial practice.
In a new study published Thursday in Science, researchers have found that honeyguide birds in Tanzania and Mozambique distinguish between honey-hunters' calls, responding more readily to signals used in their local area.
"The assignment of meaning to arbitrary or semi-arbitrary sounds is one of the features that characterizes human language," joint lead author Claire Spottiswoode, an evolutionary biologist at the University of Cambridge, told AFP.
The new research shows this phenomenon "extends to our interactions with other species, showing how continuous we really are with the rest of the natural world."
The Hadza, a group of hunter-gatherers in northern Tanzania, use a melodic whistle to initiate a partnership with honeyguides, while the Yao people of Mozambique use a trill followed by a grunt that sounds like "brrr-hmm!"
Once a nest is found, the humans crack it open, harvesting the honey and bee larvae, while the birds feast on the exposed beeswax.
Using mathematical models and audio playback, Spottiswoode and her co-author Brian Wood, a UCLA anthropologist, studied these signals, how helpful they were for people, and their effects on the birds.
They found the honeyguide birds of Tanzania were more than three times more likely to cooperate after hearing local Hadza whistles compared to "foreign" Yao calls.
Conversely, the honeyguides of Mozambique were almost twice as likely to seek a partnership after hearing a Yao trill-grunt than a foreign Hadza whistle.
The authors called this an example of "cultural coevolution," with humans of an area more likely to be successful if they stick to the local tradition, just as the birds of that region keep their ears out for the specific local call.
As for why such stark differences arose between the communities, practical considerations may be at play.
The Hadza hunt mammals using bows and arrows, and using a bird-like whistle reduces the chances of frightening away the other prey they are also after.
The Yao, meanwhile, don't hunt mammals and their trill-grunt might be a good way of scaring off elephants or buffaloes whom they don't wish to startle in a close encounter.
"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.
- A dying practice -
How exactly honeyguides learn localized human calls is an area for future study.
Perhaps they watch and copy the behavior of older birds, or perhaps they form positive associations between the human signal and a reward.
Nor is it known just how far this partnership goes back.
Our pre-Homo sapien ancestors acquired mastery of fire and stone tools between 1.5 - 3 million years ago, respectively, and so "it's plausible that this relationship could be really ancient," said Spottiswoode.
It wasn't until a seminal study published in 1989 that the scientific world was convinced the honeyguide-honey hunter relationship was real, not just a folktale or superstition.
But the practice is slowly dying out, partly as a result of changes in the way people obtain sweet food, and partly because people are prevented from interacting with honeyguides in protected nature parks.
"The birds still call to us, but we don't necessarily follow them," said Spottiswoode.
"We should really treasure these remaining places where the relationship still thrives and where this rich interspecies culture still exists."
H.E.Young--AMWN