Molecular diversity and evolution of neuron types in the amniote brain.

The existence of evolutionarily conserved regions in the vertebrate brain is well established. The rules and constraints underlying the evolution of neuron types, however, remain poorly understood. To compare neuron types across brain regions and species, we generated a cell type atlas of the brain of a bearded dragon and compared it with mouse datasets.

A claustrum in reptiles and its role in slow-wave sleep.

The mammalian claustrum, owing to its widespread connectivity with other forebrain structures, has been hypothesized to mediate functions that range from decision-making to consciousness. Here we report that a homologue of the claustrum, identified by single-cell transcriptomics and viral tracing of connectivity, also exists in a reptile-the Australian bearded dragon Pogona vitticeps. In Pogona, the claustrum underlies the generation of sharp waves during slow-wave sleep.