Reptiles
Tree Lizard
Urosaurus ornatus · also called tree lizards
A male tree lizard clings vertically to a canyon wall and flashes his colourful throat fan at a rival, a display whose exact colour scheme would look noticeably different if the same species were spotted just a valley away.
Overview
The tree lizard, Urosaurus ornatus, is a small, highly adaptable climbing lizard native to desert and forest edge habitat across the southwestern United States and northern Mexico. Its regionally variable throat-fan displays, exceptional vertical climbing ability, and subtle colour-shifting camouflage make it one of the more behaviourally and visually diverse small lizards in the American Southwest.
A display that changes by region
Travel across the tree lizard’s range and its males’ throat-fan colours shift right along with it, turning a single species’ courtship display into something closer to a set of regional variations on the same basic theme.
Status
Least Concern — widespread and common across suitable desert and forest edge habitat throughout the southwestern United States and northern Mexico.
Tree Lizard: common questions
What is the throat fan on a male tree lizard for?
A male tree lizard extends a brightly coloured throat fan called a dewlap during territorial and courtship displays, using it to signal to rival males and potential mates, with the exact colours and pattern of the dewlap varying noticeably between different populations across the species' range.
Can a tree lizard really change colour?
To a degree, yes — this species can adjust its body colouration somewhat to better blend into the bark, rock, or vegetation it happens to be resting on, though the change is more subtle than the dramatic colour-shifting seen in some other reptile groups.
Why is the tree lizard such a good climber?
This species has a notably slim, lightweight build combined with strong grip, adaptations that let it balance and move easily along narrow tree branches and rock crevices, habitats where a bulkier lizard would struggle to find secure footing.
Does the tree lizard look the same everywhere it lives?
Not necessarily — this species shows meaningful variation in size, colour, and dewlap pattern across its extensive range, meaning populations from different regions can look distinctly different from one another despite belonging to the same species.