5things we learned this week

1 Jubilee celebrations date back more than 5,000 years. Back then, says online magazine Mental Floss, Egyptian pharaohs had the knees-ups to mark 30 years in the job. They would ‘make various offerings to the gods’, and then be ‘recrowned’ in a lavish ceremony. But in order to qualify, the venerable ruler first had to put on a short kilt with a bull’s tail attached and run as fast as they could around a specially constructed race track through their palace grounds. If they couldn’t complete the course, they would be ‘promptly sacrificed’ and replaced with a younger, fitter successor.

2 There’s an island off the coast of Puerto Rico that is home to 1,500 monkeys and no humans. The 38-acre Cayo Santiago, widely known as Monkey Island, acquired its simian population in the late 1930s, when the primatologist Clarence Carpenter brought over 450 of the creatures from India. The monkeys destroyed pretty much all the natural vegetation, so now a group of humans arrive by boat once a day, toss them some food, then leave.

3 Recycling plastic doesn’t really work. The fundamental problem is that there are thousands of different plastics, each with their own composition and characteristics, says The Atlantic. And they can’t be recycled together. The proof is in the numbers: whereas America recycles 68 per cent of its paper, it manages just five per cent of its plastic waste.

4 Jackdaws have a democratic process to decide when to leave their roosts. When one of the birds wants to set off, it calls out to the others, who chime in with their votes. The quicker the sound builds, the sooner the flock leaves: if there’s broad popular support, all the birds can be out of the nest in as little as four seconds. But if they fail to reach a consensus, they fly away in dribs and drabs.

5 Young couples in Japan can get paid to move into housing complexes full of elderly people. Chiba, a city east of Tokyo, is offering newlyweds under-39 almost £2,000 to shack up alongside oldies ‘in an effort to reverse the area’s ageing population’, says Vice magazine. Japan has the world’s oldest population, and in some Chiba apartment blocks the majority of residents are over 65.

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