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2022 完形填空(英语一)

The idea that plants have some degree of consciousness first took root in the early 2000s; the term "plant neurobiology" was coined around the notion that some aspects of plant behavior could be compared to intelligence in animals.

Though plants lack brains, the firing of electrical signals in their stems and leaves nonetheless triggered responses that hinted at consciousness, researchers previously reported.

But such an idea is untrue, according to a new opinion article.

Plant biology is complex and fascinating, but it differs so greatly from that of animals that so-called evidence of plants' intelligence is inconclusive, the authors wrote.

Beginning in 2006, some scientists have argued that plants possess neuron-like cells that interact with hormones and neurotransmitters, forming "a plant nervous system, analogous to that in animals," said lead study author Lincoln Taiz, "They even claimed that plants have 'brain-like command centers' at their root tips."

This perspective makes sense if you simplify the workings of a complex brain, exposing it to an array of electrical pulses; cells in plants also communicate through electrical signals.

However, the signaling in a plant is only superficially similar to the firing in a complex animal brain, which is more than "a mass of cells that communicate by electricity", Taiz said.

"For consciousness to evolve, a brain with a threshold level of complexity and capacity is required," he added.

"Since plants don't have nervous systems, the chances that they have consciousness are effectively zero."

And what's so great about consciousness, anyway?

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