With their worm-like bodies and powerful burrowing heads, amphisbaenians have long been a mystery to taxonomists and evolutionary biologists alike. Over the past century, they have been aligned with everything from snakes to various lizard clades, while their in-group relationship remain obscure. This is largely due to the vast amounts of homoplasies both within and between amphisbaenians and other limbless squamates, which tend to converge on similar head and body shapes under the pressures of a burrowing lifestyle.

My DFG-funded postdoc at the Museum für Naturkunde Berlin sought to tease apart these factors to identify the timing and sequence of events leading to fossorality and limb loss from a terrestrial limbed ancestor. The fossil record is critical to reconstructing this transformation, which we demonstrated using CT scans of the Eocene amphisbaenian Spathorhynchus fossorium from the Green River Formation, USA.

By tracking anatomical changes across the amphisbaenian phylogeny, we confirmed several instances of parallel evolution and reversals of supposedly ‘unique’ traits associated with fossoriality, suggesting a far more complex character history than previously thought.

I am also interested in the development and morphology of living amphisbaenians, particular regarding constraints on phenotypic evolution (e.g., the West African Coast worm lizard Cynisca leucura, the Caribbean radiation) and geographic distributions (the Florida worm lizard and Rhineuridae).