Smarty Plants - "What a Plant Knows" by Daniel Chamovitz
When a plant is moved from one place to another in the house
or in your garden, you are usually trying to place it where it will grow more
successfully. Maybe the flowers were sparse or the stems were long and lanky or
the leaves were becoming crisp. Whatever signs prompted the observant gardener
to move it; the plant somehow signaled its need for different conditions and
got what it needed.
Scientists think plants know more than we give them credit
for and that our interactions with them would benefit from understanding what
has been discovered over the past decades.
In a new book, “What a Plant Knows”, scientist Daniel
Chamovitz explains how plants see, smell, feel, hear, understand where they
are, and remember. To help us understand the new science, Chamovitz compares
each sense we think of as being human and animal with the counterpart senses of
plants.
For example, plants use a set of genes to determine whether
they are located in the light or in the dark. Those same genes are in human and
animal DNA and serve the identical purpose – a response to light.
Chamovitz points out that plants have a more difficult
survival situation than humans and animals: While we have the mobility to move
away from undesirable circumstances, plants have to hold their ground and adapt
to whatever comes their way, including changing weather, pests, and encroaching
neighbor plants.
In response to their challenging environmental
circumstances, over time, plants developed sensory and regulatory systems that
they use to change their growth pattern in order to cope.
Plants see how much light they are in and the direction it
is coming from. They do not have an animal’s biological eyes but gardeners know
that when shaded, plants will move toward the light, even though they often
have to lean and become long and lanky.
They also can smell when their fruit is ripe, when a plant
nearby is being eaten by an insect and when someone has cut another plant’s
stems. One study even found that plants could smell whether they were next to
tomatoes or wheat.
Another example of plants’ ability to smell is that an
avocado will ripen if put into a bag with a ripe banana and that tomatoes will
ripen if put into a bag with an apple. Both apples and bananas emit ethylene
gas. Plants’ use of ethylene developed as a way to protect themselves from
drought, wounds, and aging.
Plants know when they are being touched, can tell the
difference between hot and cold, and vines know when there is a nearby plant or
fence to climb. The Venus Flytrap can feel the difference between wind blowing
and a frog walking across the hairs that signal it to close. It even knows
whether the prey is large enough to bother with, by the number of hairs that
are disturbed and how many seconds there were between the triggering of the
first and second hair.
Scientists found that plants do not particularly enjoy being
touched by us and will stop growing if touched too often.
Despite a hundred years of scientific experiments to try to
prove otherwise, Chamovitz concludes that plants cannot tell the difference
between Bach and rock music.
They can tell up from down, though. A plant whose pot falls over will continue to
grow upward, even if that means completely reversing direction. Plants were
sent to outer space to prove that it is gravity that makes roots grow down.
How Do Plants Know Which Way Is Up And Which Way Is Down? |
Loaded with fascinating information about plants: “What a Plant Knows: A Field Guide to the
Senses” by Daniel Chamovitz, 177-pages, published 2012, Scientific
American/Farrar, Straus and Giroux, www.fsgbooks.com.
Chamovitz’s blog is www.thedailyplant.com.
Comments
I'm sure it's in there, but plants are like animals and humans in the way that they respond to electricity... It is well known that skin wounds from minor to severe can be healed at a much faster rate when exposed to minute electric currents over the skin.
Similarly, plants that receive electrical stimulus can also experience rapid healing from wounding, fungal infections, and various forms of bacterial and viral diseases!
Part of the book was beyond my science vocabulary and understanding but what a great read!
I hope you pick it up and enjoy Chamovitz's summaries.
Oh, and, I put a link to his blog in my post. It's also very worthwhile.