Did you know that all plants forage for food in much the same way as a bear or a squirrel?
Scientist JC Cahill has shown that when plant roots come across a patch of nutrients, they slow down their growth in order to eat, just as a bear slows down its legs to graze on a berry patch. Only when the food is exhausted does the root, like the bear, move on to greener pastures.


Sunflower (CBC/Merit Motion Pictures)

Did you know that plants that can "talk"?
In fact all plants use chemical signals – compounds produced in their flowers and leaves to do a host of things, from calling in pollinators, to sending out SOS messages: distress signals that are specifically designed to call in the "enemies of their enemies", that is, insect allies that eat the insects that eat them.

Did you know that plants, like animals, can sense when they're under attack and can actually defend themselves?
One of the ways the wild tobacco plant defends itself is by ramping up the production of a toxin in its leaves called nicotine, a poison that paralyzes most plant-eating insects.

Did you know that some plants can "tag" insects for predation?
The wild tobacco plant, for instance, produces a sweet, sugary treat on its stems and leaves that scientist Ian Baldwin has dubbed the "evil lollipop," because it gives leaf-eating caterpillars, which are immune to nicotine, a bad case of body odour. That body odour then alerts ground predators like lizards that caterpillars are available for easy eating.

Did you know that the roots of an Eastern European invader called Spotted Knapweed can capture and hold territory by waging chemical war on other plants?
Knapweed deploys a chemical to uptake nutrients, which kills off a lot of native North American plants.

Did you know that there's a parasitic plant that can actually identify and choose between two different plant hosts by sniffing out their chemical IDs?
Scientists have shown that when presented with two potential victims – wheat and tomato seedlings - the parasitic dodder vine repeatedly chooses the juicier tomato host. And it makes its choice by "sniffing out" the different chemical scents released by the plants as they breathe.


Plant roots (CBC/Merit Motion Pictures)

Did you know that a plant that grows on the shores of the Great Lakes can identify its relatives and even help them out?
Scientist Susan Dudley has shown that sea rocket roots can recognize their kin via the chemical signals released by their roots and will actually restrain their own root growth rather than compete for food, when growing next to their siblings.

Did you know that some plants can tell which insect is eating it by the chemicals in the insect's saliva?
Scientist Ian Baldwin has shown that the wild tobacco plant not only recognizes its herbivores but also tailors its defenses differently depending on which insect is eating it.

Did you know that plants emit a chemical scream for help when they're under stress, and that other plants can listen in on their SOS messages?
In Africa, scientists discovered that acacia trees being decimated by animal herbivores sent out chemical distress signals that were picked up by other trees. And even though they weren't yet being munched on, the "listening" trees started ramping up their defenses as if anticipating an attack.

Did you know that "mother" trees can actually nurture their young?
Scientists Suzanne Simard has demonstrated that with the help of vast underground fungal networks, mature douglas fir trees can transport their excess carbon-based food to younger more vulnerable trees.


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