Biology Researchers solve mystery of patterns on gecko skin

Scientists at the University of Geneva have solved the mystery surrounding the skin patterns of leopard geckos. The disappearance of a cell type causes the leopard pattern on the geckos' skin, as the researchers showed in a study.

During their first months of life, leopard geckos are striped like zebras. When the animals grow up, these stripes on the gecko's skin turn into spots. The researchers wanted to better understand this transformation, as the University of Geneva announced on Wednesday.

To do so, they analyzed skin samples from leopard geckos at various stages of their lives. They found that three types of pigment cells are present in striped young animals. However, one type of pigment cells, the so-called iridophores, disappear as the animals grow up.

Tails always grow back spotted

Further proof that the lack of iridophores leads to spotted skin was provided by an analysis of the tails of leopard geckos. If these are cut off, they grow back. Regardless of the age of the gecko, the regrown tail is always spotted and never striped. Analysis of the skin of these regrown tails showed that they contained no iridophores.

The researchers carried out further tests on geckos with a special mutation. Leopard geckos with the "Mack Super Snow" mutation are completely black as young animals before they develop spots like their conspecifics as adults. In addition to the iridophores, another type of pigment cell was missing in the skin of these geckos.

According to the researchers, this shows that an interaction of two pigment cell types is responsible for the stripe pattern of the young animals, but that one pigment cell type can form spots without the help of other pigment cells. The researchers published these results in the journal "Pnas".

SDA