Earth's climate is more imbalanced than at any other time on record, with 2015-2025 confirmed as the hottest 11 years on record, as highlighted by the World Meteorological Organization's annual State of the Global Climate report.
Millions of people have a heart rhythm disorder called atrial fibrillation, which causes the heart's upper chambers or atria to beat chaotically rather than in a smooth, coordinated rhythm.
Bacterial meningitis is once again in global headlines, with recent cases linked to the University of Otago in New Zealand and a fast-growing outbreak at the University of Kent in England.
Early signs of Alzheimer's disease may be hidden in the way a person speaks, but it's not yet clear which details of our diction are most critical for diagnosis.
When a virus jumps to humans from another species, it can seem like a supervillain bent on world domination - especially if it goes on to ignite a pandemic, as many zoonotic viruses have done in recent decades.
Comb jellies - very simple, gelatinous creatures best-known for their hypnotic underwater light shows - first appeared in Earth's oceans around 550 million years ago.