Cheryll Anne Tickle (born 18 January 1945) is a British scientist, known for her work in developmental biology and specifically for her research into the process by which vertebrate limbs develop ab ovo.

At this time, she decided that she was going to focus on the effects of positional or pattern information on the sorting out process of cells during the limb development of chicken embryos.

Tickle’s experiments in his lab on embryonic chicken wings did find that the type of digit that developed did depend on its distance from the polarizing region.

These results were important in the field of developmental biology at this time, as it suggested that this model would be a definitive way of understanding how the polarizing region or ZPA worked.

There was also little known about what other chemicals were utilized during development, so the beads were soaked in many other substances thought to be significant, including insulin which was suggested to lead to duplication of limbs in ducks.

Cheryll Tickle worked alongside Eddy De Robertis and Denis Duboule to look at Hox gene expression in developing limbs to relate it to chicken wing patterns.

[21] Tickle also worked with Gail Martin and Lee Niswander in 1994 to find that fibroblast growth factors (FGF) are what is used by the apical ectodermal ridge for signaling.

A student in Tickle’s lab found that the placement of a bead soaked with FGF for only a few hours could induce the development of a new limb where one would not naturally form.

It was concluded that FGF signaling must be turned off following the completion of limb development or else the organism risks additional digit formation and other abnormalities taking place.