QUESTIONS

Q: Can any ornithologist explain why the swallows nesting in my garage fly all the way from Southern Africa to Northern Europe to reproduce? Why don’t they simply wait for the southern hemisphere summer? David Roy, Valencia, Spain.

Q: What is the farthest you can drive in a straight line without crossing a major body of water? Marcus Wilson, Hereford.

Q: Which planetary body is closest to the centre of our galaxy? Paula Dovey, Winchester, Hants.