Kenyan chameleons that were introduced to Hawaii about 50 years ago have evolved brighter colors. This change is likely due to the fact that they have fewer predators to hide from.

Jackson’s chameleons, which are native to Kenya, are known for changing color based on their surroundings. Males change to yellow to attract females or to assert dominance, and switch to green and brown to blend in with vegetation and avoid predators.

In 1972, approximately 36 Jackson’s chameleons were brought from Kenya to Hawaii by a pet shop owner. After they escaped into the wild, they were able to thrive in Hawaii due to the lack of natural predators.

Researchers at Macquarie University in Sydney, Australia, led by Martin Whiting, conducted experiments using male Jackson’s chameleons from Hawaii and Kenya. They exposed the chameleons to other males, females, model birds, and model snakes to observe their color changes in response.