Lizards living in different cities have parallel genomic markers when compared to neighboring forest lizards, according to a new study. The genetic variations linked to urbanization underlie physical differences in the urban lizards, including longer limbs and larger toe pads that show how these lizards have evolved to adapt to city environments.Lizards living in different cities have parallel genomic markers when compared to neighboring forest lizards, according to a new study. The genetic variations linked to urbanization underlie physical differences in the urban lizards, including longer limbs and larger toe pads that show how these lizards have evolved to adapt to city environments.