Why do women live longer than men?

In the UK today, male life expectancy is 78 years old, whereas women will on average live four years longer.

Evolutionary biologist Dr Yan Wong looks at the latest evidence suggesting that where ageing is concerned, men seem to be at a genetic disadvantage. From research on ancient Korean eunuchs to laboratory fruit flies, new studies seek the answer to why males across the animal kingdom live faster and die younger.

So, is the gender gap here to stay?