Scientists have discovered a tropical insect that changes color from bright hot pink to green in about two weeks. Researchers believe this dramatic change allows them to mimic the young leaves of rainforest plants, which often start out pink before turning green.
The discovery was reported this week in the journal ecologymainly alota festivalthe leaf-mimicking katydid, also known as the “bush cricket.” This species is found in parts of Central and South America, including Panama, Colombia, and Suriname.
Unusual observations in Panama
This unusual color change was first noticed when researchers discovered the adult female at the Smithsonian Tropical Research Institute field station on Panama’s Barro Colorado Island. When we first saw her under the light, her color was a striking hot pink. After just 11 days, she was completely green.
Mimic the changing color of leaves in a rainforest
A team from the University of St. Andrews, the University of Reading, the Smithsonian Tropical Research Institute, and the University of Amsterdam suggests that this color change may be related to a natural process known as “delayed greening.” In many tropical plants, newly emerging leaves appear in shades of bright pink or red, gradually turning green as they grow.
On Barro Colorado Island, approximately one-third of the plant species exhibit this pattern throughout the year. This provides a consistently pink leaf background, allowing similarly colored insects to hide from predators.
Possible survival strategies, not mutations
Lead author Dr Benito Wainwright from the University of St Andrews said: “The discovery of this specimen was a real surprise. It was so rare that we kept it in its natural state and discovered that its color had changed from deep pink to green.”
“Rather than some strange genetic quirk, this may actually be a finely tuned survival strategy that tracks the life cycle of the rainforest leaves that this insect is trying to mimic.”
To better understand this process, the researchers reared the insects for 30 days and photographed them every day. The bright pink started to fade after 4 days to a soft pastel hue. By the 11th day, the insect looked like a typical green figure.
Unprecedented color shift
The grasshoppers lived long enough to mate, but died naturally the following month.
Pink katydids have been recorded in the scientific literature since 1878, but have typically been considered a rare and disadvantageous mutation. This observation appears to be the first recorded instance of a katydid completing a full-color transition within a single stage of its life.
Camouflage in complex ecosystems
Co-author of the study, Dr Matt Greenwell from the University of Reading, said: “Tropical forests are very complex environments and this discovery suggests how precisely some animals have evolved to use them.”
“You would think that a bright pink insect in a mostly green forest would stand out to predators, like a worker wearing a high-visibility jacket. The idea that insects might gradually change color to match the leaves they mimic shows how dynamic rainforests are, and is a remarkable example of camouflage in action.”
