The way Pacific Islanders used to navigate using only cues found in the environment may seem irrelevant today. But natural navigation still holds surprising lessons.
Britain's most famous tree had stood at Sycamore Gap along Hadrian's Wall in Northumberland for 300 years before it was felled on Wednesday night with a chainsaw.
The fallen tree in England, which dates from the 18th century, was discovered by walkers in Northumberland after someone took a chainsaw to its trunk overnight.