One down, 39,136 to go: the explorers who walk every street in their city
You don’t really know an urban landscape until you’ve visited all of it on foot – from slums to beauty spots. Just ask the thousands of ‘every-single-streeters’
Seven hours’ sleep is ideal amount in middle to old age, study finds
Too much and too little sleep linked with worse cognitive performance and mental health
‘Some people are freaked out’: how Laetitia Ky tackles abortion, sexism and race with her extraordinary hair
From vacuum cleaners to menstruation, the Ivory Coast artist and activist creates incredible sculptures with her hair to tackle taboos. She talks about how learning to love her natural hair taught her to love being a black woman – and western criticism of her work
Not Going Quietly review – healthcare activist Ady Barkan takes ALS to congress
Documentary follows Barkan, who has motor neurone disease, as he campaigns for better public healthcare in the US
Bless you! Meet the flu hunters trying to stop the next pandemic in its tracks
Remember flu? Despite lockdowns holding it at bay, a small group of scientists is searching the globe for deadly new strains – and to work out what to put in next winter’s vaccines
‘Will the babies be left in a war zone?’ The terrified Ukrainian surrogates – and the parents waiting for their children
The Russian invasion has put surrogate mothers in a desperate position – and left foreign couples fearing the worst
US boy with uncombable hair syndrome becomes Instagram hit
Locklan Samples of Georgia has a rare condition that means his hair stands out from the scalp and cannot be combed flat
Reasons to be cheerful: optimists live longer, says study
Those with a positive attitude to life may lower their anxiety levels by avoiding arguments or not perceiving traffic jams as stressful
‘Aggressive’ marketing of formula milk flouts code, warns WHO as it urges curbs
‘Misleading’ messages from $55bn-a-year industry are ‘unethical’, says report, which calls for plain packaging rules similar to tobacco
The herbalists of Tunis medina: on borrowed thyme – a photo essay
From the cavernous shops in Souq El Blat, herbalists share the rich and fascinating history of their proud and ancient trade – and their fears that it could disappear