Plants do sums to get through the night, researchers show

Plants do sums to get through the night
Professors Martin Howard and Alison Smith

( —New research shows that to prevent starvation at night, plants perform accurate arithmetic division. The calculation allows them to use up their starch reserves at a constant rate so that they run out almost precisely at dawn.

"This is the first concrete example in a fundamental of such a sophisticated arithmetic calculation." said mathematical modeller Professor Martin Howard from the John Innes Centre.

Plants feed themselves during the day by using to convert carbon dioxide into sugars and starch. Once the sun has set, they must depend on a store of starch to prevent .

In research to be published in the open access journal eLife, scientists at the John Innes Centre show that plants make precise adjustments to their rate of starch consumption. These adjustments ensure that the starch store lasts until dawn even if the night comes unexpectedly early or the size of the starch store varies.

The John Innes Centre scientists show that to adjust their starch consumption so precisely they must be performing a – arithmetic division.

"The capacity to perform arithmetic calculation is vital for and productivity," said metabolic biologist Professor Alison Smith.

"Understanding how plants continue to grow in the dark could help unlock new ways to boost crop yield."

During the night, mechanisms inside the leaf measure the size of the starch store and estimate the length of time until dawn. Information about time comes from an , similar to our own . The size of the starch store is then divided by the length of time until dawn to set the correct rate of starch consumption, so that, by dawn, around 95% of starch is used up.

"The calculations are precise so that plants prevent starvation but also make the most of their food," said Professor Smith.

"If the starch store is used too fast, plants will starve and stop growing during the night. If the store is used too slowly, some of it will be wasted."

The scientists used mathematical modelling to investigate how such a division calculation can be carried out inside a plant. They proposed that information about the size of the starch store and the time until dawn is encoded in the concentrations of two kinds of molecules (called S for starch and T for time). If the S molecules stimulate starch consumption, while the T molecules prevent this from happening, then the rate of starch consumption is set by the ratio of S molecules to T molecules, in other words S divided by T.

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More information: Scialdone et al. Arabidopsis plants perform arithmetic division to prevent starvation at night, eLife 2013;2:e00669. To be available at DOI: 10.7554/eLife.00669
Journal information: eLife

Provided by John Innes Centre
Citation: Plants do sums to get through the night, researchers show (2013, June 23) retrieved 15 October 2019 from
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Jun 23, 2013
Math? Really? Is this actual calculation or just the fine tuning of natural selection? Is a simple math test in order here to verify this?

Biological entities have evolved various mechanisms to optimize resources, but calling it math does seems a bit odd.

Jun 23, 2013
And rocks compute their acceleration due to gravity as they fall.

Do you think that Rocks are smarter than this Republican?


Jun 23, 2013
Biological entities have evolved various mechanisms to optimize resources, but calling it math does seems a bit odd.

I was going to make a frivolous comment lampooning the absurdity of this research, but I had second thoughts after I went outside and saw how the weeds in my garden had multiplied.

Jun 23, 2013
" had multiplied." - Frilla

Indeed they can compute exponents.

A spinning wheel is smarter than the average American HS student since a spinning wheel computes complex exponents.

-1 = e**(I*pi)

is no mystery to a spinning wheel.

Jun 24, 2013
Now you have me worried; what does it mean if my Chinese cabbages are out there doing differential calculus?

Imagine the structural engineering calculations. Plants have to make roughly accurate forecasts of weather extremes including wind gusts, to calculate stem girth and root strength. The simulation software that deciduous trees employ is state-of-the-art.

Jun 24, 2013
That's fine as a bold Popperian hypothesis. Now go isolate those molecules and remove one to see what happens.

Jun 24, 2013
I have to admit I'm divided on what to think about this. On the plus side, that is a very nice picture of our two intrepid scientists standing by with an emergency flashlight, should one of their plants miscalculate its starch reserves and enter into metabolic distress. I'd give them an A minus for that.
I wonder if their plants have square roots?

Jun 24, 2013
"what does it mean if my Chinese cabbages are out there doing differential calculus?" - Rob

It means you have far more to fear than the coming Zombie Apocalypse.


You have been warned.

Jun 24, 2013
So sockpupper VD, now will come deepsand, sinister1811 8 ball and 6 of 28 to rank you up.

It's always interesting that these other names crop up most often in the same order.

Progressives such as you lie, cheat, steal, vote, and vote often.

Jun 24, 2013
And dogs solve calculus equations when they catch a ball, right?

"Science journalist" is just a way of getting paid to be bad at two things at once.

Jun 24, 2013
Dope plants just get the munchies and scoff the lot in one sitting.

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