Geckos and chameleons are both lizards, but they have very different abilities when it comes to changing color. Chameleons are famous for their ability to change their skin color rapidly according to their surroundings. Geckos, on the other hand, don’t have this same talent for color changing.
How chameleons change color
Chameleons have special pigment cells called chromatophores in their skin that allow them to change color quickly. There are several different types of chromatophores:
- Xanthophores – contain yellow and orange pigments
- Erythrophores – contain red pigments
- Cyanophores – contain blue pigments
- Melanophores – contain black/brown pigments
- Iridophores – reflect light to create metallic and iridescent colors
By dispersing or concentrating these pigments within the chromatophore cells, chameleons can change their skin from bright green to dark brown, pink, orange, black, blue and more. They use color change as camouflage to hide from predators and prey. Their changes in color are rapid, happening in seconds or minutes. Chameleons can also show darker emotions like anger or fear through darker skin pigmentation.
How geckos change color
Geckos do not have the specialized chromatophore cells that allow chameleons to change color so quickly. However, they do have some more limited abilities to alter their skin color.
Geckos can change color through two methods:
- Physical color change – Gecko skin has pigment cells called melanophores that contain melanin. These cells can spread out or contract to alter skin darkness. This process happens slowly, over hours, days or weeks. It allows geckos to darken their skin to better camouflage with their surroundings.
- Physiological color change – Geckos can sometimes change color more rapidly by changing blood flow to the skin. Increased blood flow makes the skin appear reddish or pink. Decreased blood flow makes the skin paler. But geckos have limited control over blood flow compared to chameleons.
So while geckos can blend in with their surroundings a bit by darkening their skin, they cannot quickly flash different bright colors like chameleons can.
Reasons for color changing abilities
There are a few theories as to why chameleons developed such strong color changing abilities while geckos did not:
- Chameleons are arboreal, living mostly in trees and shrubs. The ability to instantly change color helps them blend in with foliage as they move around branches. Geckos live mainly on the ground.
- Chameleons are ambush predators, relying on stealth and camouflage to catch prey. Rapid color change helps them sneak up on their targets. Geckos are active foragers, moving around more to hunt insects.
- Chameleons use color signals for communication between members of their own species. Bright colors can reflect excitement, aggression or mating interest. Geckos do not seem to rely on color signals in the same way.
- The chameleon’s color changing ability evolved from skin cells that also help them regulate temperature. Geckos use their scales for temperature control instead.
So in summary, chameleons evolved specialized color changing cells to help them thrive in their arboreal, ambush hunting lifestyles in tropical forests. Geckos did not face the same pressures, so did not develop this ability to the same extent.
Other color changing lizards
While chameleons and geckos are some of the most well-known color changing lizards, there are a few other species with limited color changing abilities:
- Bearded dragons – Can change from light to dark colors, but only over longer periods of time
- Uromastyx species – Can change from dark to light, depending on temperature
- Pink tongued skinks – Develop temporary dark banding when stressed or cold
- Crested geckos – Can lighten or darken skin slightly based on temperature and mood
However, none of these lizards have the speed or range of color change seen in chameleons. The panther chameleon is especially vibrant, able to show a wide rainbow of colors.
Role in captivity
Both chameleons and geckos are popular exotic pets. Their color changing abilities play an important role in how they are cared for in captivity:
- Chameleon owners need large, well planted terrariums and cages to give their pet places to show off color changing abilities.
- Chameleons should not be housed with other chameleons, since color signals are used for territory defense.
- Gecko enclosures can be simpler, but should simulate their natural habitat with places to hide and control temperature.
- Handling a chameleon can stress it and cause more drab coloration. Geckos are hardier when handled.
- Bright overhead lights are important for both chameleons and diurnal geckos to allow their colors to show properly.
So a key part of caring for these lizards in captivity is providing environments where their natural coloration and color changing behaviors can be displayed.
In summary, while geckos have some limited ability to alter their skin color over time, chameleons far surpass them with their rapid chromatic abilities. Chameleons evolved specialized skin cells and communication methods involving color change that geckos simply don’t possess. Both reptiles are fascinating examples of color change in the natural world, but for dazzling color shifts, chameleons stand alone.