Meroles cuneirostris STRAUCH, Alexander, G. Arnold, E. Estimates of phylogeny may allow historical events to be reconstructed even without a fossil record. The reliability of such interpretations depends not only on the robustness of the phylogeny but also on its topology. Changes in individual features can be traced and general histories of groups developed and compared with each other.
Results are ofter surprising, for Instance the sophisticated tail shedding mechanism of lizards turns out to be a primitive feature that has been lost many times. Similarly, ecological analogues may have developed their common characaters in quite different orders. Phylogenies also provide a way of recognizing constraints and the effects of history on present ecological and behavioural patterns.
When using anatomical characters the quality of the apparent phylogenies produced may be related to ecological history: expansion of a group along an ecological continuum into increasingly demanding niches ina small geographical area tends to produce a robust phylogeny for instance in Meroles , while this is often not so for widely distributed groups that occupy a more modest range of niches such as Pedioplanis and Podarcis. Non-morphological data may not show this tendency, but can have their own problems.
Lacertids can be referred to clade with many successive branches in Africa and the Saharo-Eurasian arid zones and a less resolved probably paraphyletic complex of more primitive forms in the Mediterranean and wider Palaearctic areas.
The African-Eurasian clade shows a general trend towards ground-dwelling and increasingly arid habitats but is ecologically variied.
