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Inside the pupa (or chrysalis), the caterpillar actually turns to liquid during metamorphosis. Despite such an extreme transformation, the butterfly or moth can retain learning from its caterpillar days.

Do you remember being a newborn? I don’t think our species is capable of that kind of remembering. What about other species? Recent research suggests that butterflies have a kind of muscle memory from the good old days of their caterpillar-hood.

An article from Curious Kids — a series that gets experts to answer questions that kids send in — has the scoop. Evan, age 5, asked the question.

“We have caterpillars at home. I would like to know whether they will remember being caterpillars when they are butterflies.”

“Dear Evan,

“I think it is highly unlikely that a butterfly or moth remembers being a caterpillar. However, it may well remember some experiences it learned as a caterpillar.

“That fact in itself is especially amazing because inside the pupa (or chrysalis), the caterpillar actually turns to liquid as it transforms into a butterfly or moth (the adult stage).

“The transformation from the pupa to the adult is the most dramatic change in the life cycle of a butterfly, and scientists refer to this change as metamorphosis. During metamorphosis, the body tissues of the caterpillar are completely reorganised to produce the beautiful adult butterfly that emerges from the pupa.

“Scientists have known for a long time that caterpillars can learn and remember things when they are caterpillars, and adult butterflies can do the same when they are butterflies. However, because of metamorphosis, we were not sure if an adult butterfly could remember things it learned as a caterpillar.

“This ability to remember caterpillar experiences as an adult was tested in a study by a team of scientists at Georgetown University in the US.

“The researchers trained the caterpillars to dislike the smell of ethyl acetate, a chemical often found in nail polish remover. They did this by giving the caterpillars little electric shocks every time they smelled the chemical. Soon, these caterpillars were trained to avoid that smell because it reminded them of the electric shock.

“They let the caterpillars transform into adult moths, and then tested the moths again to see if they still remembered to stay away from the ethyl acetate smell.

“And guess what? Most of them did! The scientists had shown that the memories of avoiding the bad smell experienced as a caterpillar had been carried over into the moth stage. …

“Thank you for sending in this very interesting question.

“Yours sincerely,

“A/Prof Michael F. Braby”

More at the Conversation, here.