On March 27, 2025, somewhere in the Panamanian rainforest, evolutionary biologist Zeke Rowe was looking for a snack. While walking outside the lab cafeteria, Rowe noticed a strange insect summoned by the floodlights. The insect was a katydid, a close relative of crickets famous for mimicking leaves. Katydids have veined bodies that are often bright green like a new leaf or spotted brown like a fallen leaf. But this particular katydid was an unnatural looking neon pink. Rowe, who studies leaf mimicry in moths, brought the pink katydid to the office of colleague Benito Wainwright, an evolutionary biologist at the University of St. Andrews in Scotland.
“I was very pleased,” Wainwright wrote in an email. For the past two years, Wainwright has been exclusively studying those katydids and how they evolved their leafy masquerade. But he had never seen a pink catid before. When he searched the literature, he found that pink katydids had been previously documented in the scientific literature. Although it does not belong to this particular species, Arota Festa. However, most of these papers were over 100 years old and contained no mention of whether pink might provide any benefit to insects. Instead, “these individuals were considered rare, monstrous mutants who were at a disadvantage due to their striking appearance,” Wainright said.
Wainwright placed the adult female pink katydid in a cage with other katydids he had collected, all of which were green. Here the insects feasted on green vegetation, apples and water. He collected these katydids to study their behavior, wing shape, and genetics, and thought he could do the same with the pink cigar. “At the time, I had no intention of specifically studying those crazy colors,” Wainwright said. In fact, he didn’t look at her closely until four days later when he realized her color was changing. He and his colleagues describe the bug’s color change in a recently published paper. ecologyThe title is “Pink Cricket Club”.
The katydid’s body has faded slightly from an intense magenta color to a pale bubblegum color. “I’m still a little annoyed that I didn’t notice it changing color sooner,” Wainwright said. He began taking pictures every 24 hours to track her changes.
After seven days, she was completely green and indistinguishable from her plant brethren in the cage. On day 10, researchers discovered she had mated with a male. A. Festa Katy Deed. The proof was in spermphylax, a delicious type of sticky substance that males give females to clump together with their sperm so they can eat it as a post-coital snack.
All insects molt throughout their lives, breaking out of old exoskeletons into new ones, giving them endless potential for rapid color changes. Take a look at the differences between baby and adult brown marmorated stink bugs. But Wainwright said he was “completely shocked” to learn that katydids can change their skin color at one stage of their lives. “I’ve never heard of an insect doing this before,” he said.
Then Patrick Cannon and Matthew Greenwall, who are also authors of the new paper, noted the ubiquity of red, white and pink leaves in the jungle. Also known as “red flush” or “delayed greening,” this is caused by reduced chlorophyll content. Flushing is a defensive strategy. Pale or pink leaves are less nutritious and therefore less likely to be eaten. This is a popular strategy in the tropics, and as researchers toured the rainforests of Barro Colorado Island, they discovered many leaves that looked exactly like the pink gradient of the katydid. Mixing in with these pink, tasteless leaves provides protection from predators.
Past descriptions of the occasional pink katydid have always been that the color was considered rare and unfavorable. Obviously, the pink body will make the insect more noticeable in the green forest. But researchers have now hypothesized that the bug’s pink hue and ability to change color may be an adaptive trait of katydids. “Are these katydids mimicking not only green leaves but also pink leaves at certain stages of development and possibly switching between these forms?” Wainwright asked. “We don’t have experimental evidence to support this, but it’s very interesting to think about, and if true it would beautifully demonstrate the interconnectedness of tropical ecosystems.”
Researchers aren’t sure what mechanism triggered the katydid’s color change. Perhaps it was a reaction to being surrounded by green katydids, i.e. green vegetation. After all, if a pink cattydid lives in a completely green tree, it doesn’t have any camouflage privileges. “Changing color allows these animals to match the most abundant colors in their environment,” Wainwright said. Or, to be more specific, the color of pink katydids typically fades as the leaves turn green. Or maybe the pink color is the result of a recessive gene. At this time, scientists don’t know enough about how the pink katydid’s color change works. Wainwright hopes to be able to test some of these hypotheses in the future, whenever he finds the time and money.
In the meantime, Wainwright continues to study how katydids evolved into a form so similar to leaves. He’s in Panama now, snooping around floodlights, especially under the crescent moon, trying to scoop up any katydids attracted to the light. He also found some katydids that resembled dead leaves with brown spots marring the bright green color of their backs. This once magenta female died of natural causes in late April, but other pink katydids still roam the rainforest, waiting for their little mystery to come to light.
