OXFORD, England, June 30 (UPI) -- Scientists have shown plants have the ability to perceive varying levels of risk and make decisions based on an understanding of variable conditions -- a first.
Scientists first showed that pea plants put out more roots in pots of soil with high levels of nutrients, just as animals devote more time and energy to foraging and hunting when food is particularly abundant.
Next, researchers split a pea plant's roots between two pots -- one with a constant level or nutrients and another with rising and falling, or varying, levels. One pair of pots featured a consistently poor quality of soil, while another pair featured an above average supply of nutrients.
Researchers hypothesized that the plants would grow more roots in the variable soil when the constant quality was low, and opt to devote root resources to the constant pot when soil quality was better.
The pea plants' roots did just that.
The adaptive behavior mimics the decision making of humans when faced with similar risk variables. Humans are generally more prone to take risk, or gamble, when they have less to lose. When times are good, there is less to gain by taking a risk.
"To our knowledge, this is the first demonstration of an adaptive response to risk in an organism without a nervous system," researcher Alex Kacelnik, a zoologist at Oxford University, said in a news release. "We do not conclude that plants are intelligent in the sense used for humans or other animals, but rather that complex and interesting behaviours can theoretically be predicted as biological adaptations -- and executed by organisms -- on the basis of processes evolved to exploit natural opportunities efficiently."
Researchers aren't sure how exactly plants sense fluctuations of available nutrients, but the latest findings -- detailed in the journal Current Biology -- suggest other models of behavioral economics could be use predict the decision making of plants.