[Trine]

This is probably a stupid question...I didn't do biology in school!

But I was wondering, since (I presume) plant life has existed for the same period of time in the same conditions and environment as animals/humans, why have they not developed an intelligence on par with animals or even humans? Even the lowliest of animal and insect life seem to have ways of communicating. Plants do not (to my knowledge).

Have their genes decided that they have fulfilled their purpose and are happy just to "be", never evolving further? I would have guessed that evolution is a never ending continuous process.

Given another few billion years, would be it conceivable for plant life to begin evolving a similar "intelligence" that we associate with animals and humans (communication, awareness of oneself etc.)?

[Capt'n Midnight]

Plants do move and communicate to a certain extent. Chemical signals are used in some cases.

On land they are pretty much tied down by the need for roots to acquire minerals, water, and whatever it is they get from the fungi on their roots.

But they don't have a nervous system nor do they need to waste energy trying to keep it running, we'd only survive a few weeks without food.


There is no one size fits all solution to life, and plants have a different tactic, they get free energy so don't need to go chasing meals, they are a lot more resistant to damage than animals, just think about mowing a lawn.

If you've ever tried to swat a fly the you'll appreciate just how fast a Venus fly trap can move.


Euglena is a fully little thing, it's got chlorophyll so it's a plant, but it swims so it's an animal. It's also got an eyespot which kinda screws up the whole "what's the point of half an eye" argument since it's a single celled organism. The boundary isn't always clear cut.

Also fungi are very different to land plants or animals.

[AlmightyCushion]

Photosynthesis doesn't exactly produce a lot of energy and a brain requires quite a lot of energy (20% of the energy a human needs is feeding just our brain). If a plant was to have a brain as complex as that of an animal it would need a lot more energy to feed it and it isn't going to get that energy from photosynthesis.

Also, you seem to be confusing evolution with intelligence. The two can be related but just because a species isn't getting more intelligent doesn't mean it isn't evolving.

[true-or-false]

Originally Posted by Trine

But I was wondering, since (I presume) plant life has existed for the same period of time in the same conditions and environment as animals/humans, why have they not developed an intelligence on par with animals or even humans? Even the lowliest of animal and insect life seem to have ways of communicating. Plants do not (to my knowledge).

Have their genes decided that they have fulfilled their purpose and are happy just to "be", never evolving further? I would have guessed that evolution is a never ending continuous process.

Given another few billion years, would be it conceivable for plant life to begin evolving a similar "intelligence" that we associate with animals and humans (communication, awareness of oneself etc.)?

Plants are very intelligent. They can't do crosswords, but that wouldn't be of much use to them if they could; they do however adapt, sense, have behaviours and in a way even remember things.

As for their evolution, evolution doesn't have an end goal. Genes can't look at a brain and say "we should try to make one of those". Plants are certainly still evolving, just as we are, so yes, evolution is a never ending continuous process.

Given enough time, plants could certainly evolve a similar intelligence to what you have in mind, they could evolve just about any characteristics given enough time, but it's highly unlikely they would, as their needs are very different to ours.

Don't underestimate them! Plants are extremely diverse and have adapted to far more environments than humans, and they do it all without iPhones If you can get access to it, have a look at "Secret life of plants: From memory to intelligence" in the journal Plant Signalling and Behaviour, by Karpinski and Szechynska-Hebda.

[roro1neil0]

You're making a fundamental mistake OP of associating evolution with linear progression from simplistic to complex.

why haven't plants evolved to be smart like people?
why haven't people evolved to source their energy directly from the sun without need to eat?
why haven't people evolved wings so they can fly to work rather than drive?