SCIENCE

Pseudoscientific claims that music helps plants grow have been made for decades, despite evidence that is shaky at best. Yet new research suggests some flora may be capable of sensing sounds, such as the gurgle of water through a pipe or the buzzing of insects. (Scientific American)

It’s a great time to play ‘Viridi’—and vocally tend your garden!

Teachers, scroll down for a quick list of key resources in our Teachers Toolkit. Heads-up: There are a lot of great links in today’s post!

Discussion Ideas

• The short Scientific American article poses the question “can plants hear?” So, what are plants? Leaf through this Encyclopedia of Life resource for some help.
  • Plants are eukaryotic organisms that are mostly multicellular and mostly photosynthetic. (Eukaryotes are organisms whose cells have differentiated organelles such as a nucleus.)
    • Most plants belong to the informal group viridiplantae, or green plants. The cells of green plants have a telltale cell wall made of cellulose. They also have organelles called chloroplasts, which contain the green pigment chlorophyll that gives the plants their name and are crucial to photosynthesis.
    • There are more than 350,000 species of plants on Earth, most of them viridiplantae.
    • Plants are found in almost every biome on Earth, from mosses in the Arctic (and, lately, Antarctic), to cacti and their relatives in the desert, to seagrasses along coastal ecosystems.
    • Flowers? Plants. Trees? Plants. Ferns? Plants. Mosses? Plants.
    • Fungi? NOT plants. Bacteria? NOT plants. Red or brown algae? NOT plants.
    • Leaf through the “tree of life” to see how plants are related.

• OK, so what is sound?
  • Sound is a series of vibrations created by waves of pressure (sound waves) and transmitted through a medium such as air or water.
    • “In space, no one can hear you scream.” That’s actually true. In the near-vacuum of outer space, there is no medium to transmit sound. (If you find yourself in interstellar space trying to scream, however, you have bigger problems than acoustics.)

• Why would it be a surprise if plants could hear?
  • Corny jokes aside, plants don’t have ears.
  • Many scientists are skeptical that plants have structural organs that allow them to detect and process sound waves.

• What scientific studies hint that plants may be able to detect sound waves—to “hear”?
  • Scientific American describes one recent study that tested pea seedlings whose roots were seemingly able to detect water flowing through hidden tubing. “They just knew the water was there, even if the only thing to detect was the sound of it flowing inside the pipe,” says one researcher.
  • Arabidopsis, a relative of cabbage, is able to “distinguish between caterpillar chewing sounds and wind vibrations—the plant produced more chemical toxins after ‘hearing’ a recording of feeding insects.”
  • Many plants, such as African violets, engage in “buzz pollination, in which a bee buzzing at a particular frequency has been shown to stimulate pollen release.” Cue this video to about 10:05 to learn more about buzz pollination.

TEACHERS TOOLKIT

Scientific American: Can Plants Hear?

Nat Geo: Game of the Week: Viridi

Encyclopedia of Life: What is a Plant?