Letters to the Editor

Readers are curious about dark matter, plastics’ effects on pollination and Percy’s selfies

Readers discuss the psychedelic psilocybin, frogs and UFOs

Readers discuss black holes’ trippy effects on time, banned swimsuits

Readers discuss hypothetical ‘tauonium’ atoms

Readers ponder sign language in ancient humans, looped universe

Readers ask about noise pollution and beluga melons

Readers discuss dark energy, Ötzi’s tattoos and sneaky plant invasions

Readers react to a rare visual disorder, microplastics in arteries and more

Readers discuss accessible images in print and potassium’s climate potential

Readers consider medical privacy, where sharks rank in food webs

Readers discuss Mimas’ hidden ocean and ancient cave art

Readers discuss ancient plagues and a fern’s leaf revival