Lizards of the Caribbean islands have changed little over millions of years.

Credit: Ettore Morone

Only three fossils of Anolis lizards have previously been studied, but now Emma Sherratt at the University of New England in Armidale, Australia, and her colleagues have analysed a further 17 fossils entombed in amber (pictured) from the Dominican Republic. The specimens, which are 15 million to 20 million years old, revealed that the animals were uniquely adapted to the different parts of the trees that they inhabit, much as they are today. For instance, lizards that lived on twigs tended to be small with short limbs. Other fossils resembled larger lizards that live near the base of tree trunks and those found around the crowns of trees.

The findings suggest that communities can remain remarkably stable over long evolutionary timescales.

Proc. Natl Acad. Sci. USA http://doi.org/6hk (2015)