BBC Knowledge June 2017

PHOTOS: GETTY X

TOP 10

1. Seagrass colony
   (Posidonia oceanica)
   100,000 years old
   Balearic Islands, Spain
   2. ‘Pando’
   Quaking aspen colony
   80,000 years old
   Fishlake National Forest,
   Utah, the USA
   3. ‘Jurupa Oak’
   Palmer’s oak colony
   13,000 years old
   Jurupa Mountains,
   California, the USA
   4. Mojave yucca
   12,000 years old
   Mojave Desert,
   California, the USA
   5. Huon pine colony
   10,500 years old
   Mount Reed,
   Tasmania, Australia

The percentage of

amphibian species at risk

of extinction. Threats are

habitat loss, pollution,

disease and climate

change.

32

The number of years ago

that humans first reached

North America – 10,

years earlier than

previously thought.

24,

IN NUMBERS

47

*Including clonal colonies with interconnected root systems, but discounting plants without reliably determined ages

The percentage of fish

that was mislabelled

in Los Angeles sushi

restaurants, according

to DNA tests.

Yes. In 2001, researchers at MIT monitored brain activity in rats as they solved a maze. They found

that the animals showed the same brain activity patterns during sleep. The match was so close that

the researchers could tell which part of the maze the rat was dreaming about. Cats and mice show similar

results, so it is likely that visual dreams are common to all mammals, including dogs. LV

Do dogs have visual dreams?

| & ANSWERS

QUESTIONS

16 June 2017

10 OLDEST PLANTS ON THE PLANET*