Strange Nature

Short, surprising cards on strange nature. Each one is labelled Established, Debated or Speculative, so you always know how solid the evidence is.

• An octopus tastes with its arms.

  Established. Octopus suckers are lined with receptors that taste what they touch. About two thirds of an octopus's neurons sit in its arms, so each arm…

• There is an animal that can survive the vacuum of space.

  Established. Tardigrades, or water bears, are about half a millimetre long. In 2007 scientists sent them into orbit, exposed to open space, and some…

• One jellyfish can turn itself young again.

  Established. When injured or stressed, Turritopsis dohrnii can turn back into an earlier life stage and start over. In theory it can do this again and…

• Do trees talk to each other underground?

  Debated. Fungi wrap around tree roots and link them in vast underground networks, sometimes called the 'wood wide web'. Some researchers say older…

• A brainless slime mould redesigned the Tokyo rail network.

  Established. In 2010, researchers placed oat flakes on a map in the positions of cities around Tokyo, with a slime mould at the centre. It spread out,…

• Crows remember your face, and tell their friends.

  Established. At the University of Washington, researchers wearing a mask trapped and released some crows. For years after, crows scolded anyone in that…

• The mantis shrimp punches so fast the water boils.

  Established. Its club-like arms strike at around 80 km/h, among the fastest movements in the animal world. The strike creates bubbles that collapse with…

• The axolotl can regrow a leg, part of its heart and even its brain.

  Established. This Mexican salamander can replace lost limbs, spinal cord and pieces of organs, without scarring. Scientists study it to learn how…

• One of the heaviest living things on Earth is a forest that is a single tree.

  Established. Pando, in Utah, looks like a grove of about 47,000 aspen trees. They all share one root system and the same DNA. Together it weighs an…

• Birds may see Earth's magnetic field using quantum physics.

  Debated. Migrating birds can sense magnetic north. A leading idea is that a protein in their eyes, cryptochrome, reacts to the magnetic field…

• Bees understand the idea of zero.

  Established. In a 2018 study, honeybees were trained to choose cards with fewer shapes. When shown a blank card, they understood it as fewer than one.…

• Monarch butterflies fly to a place none of them has ever been.

  Established. Each autumn, millions of monarchs fly up to 4,000 km from North America to the same mountain forests in Mexico. The trip north takes…

• There may be sharks alive today that were born before Shakespeare.

  Established. Greenland sharks grow about a centimetre a year in icy Arctic waters. In 2016, scientists dated the lenses of their eyes. The oldest was…

• Dolphins call each other by name.

  Established. Each bottlenose dolphin develops its own 'signature whistle'. Others copy that whistle to call it, and dolphins respond when they hear…