Question: How can a plant can form, retain, and recall its memory, just like humans do ?

Jennifer Bates answered on 16 Nov 2016:

The scientist Monica Gagliano suggested that plants do form memories and retain them, but perhaps not like humans do as they do not have brains or nervous systems like us. She performed an experiment in which she took some plants and set them in a rig that dropped them a controlled distance then stopped without hitting a surface. The first few times the plants curled their leaves in response, protecting themselves, but over time they stopped doing this as much, and after 60 times they just didn’t seem to care. She suggested this was memory. Other said it was just exhaustion, she’s knackered the plants out, it takes energy to curl up you’re leaves after all! Gagliano responded by putting the plants in a shaker (poor plants) and they instantly curled their leaves – so not tired then, frightened again! She then waited a month and tried again, and the plants didn’t curl up when dropped, suggesting they could remember even after so long (longer than bees even!).

Gagliano however doesn’t quite know how they remember this. She suggests that maybe chemicals and hormones are important in this retention of information, and is investigating further.

More recently a scientist called Karissa Sanbonmatsu has been looking at longer term memory and has pointed to the role of RNA in memory transmission and retention, but it is still early days looking at that.