Petri-dish Monday

This week we have some truly biological trees, in which the phylogeny is literally drawn by biological organisms growing in a petri dish.

The first example, a primate phylogeny, comes from the lab of T. Ryan Gregory. The image was created using live colonies of Escherichia coli bacteria. These images last only a few days, and a few others can be viewed on the lab's blog page.

The second example, showing the evolution of coral pigments, comes from the lab of Mikhail V. Matz. The image was created using colours from the great star coral, drawn on a petri dish with bacteria expressing the extant and reconstructed ancestral pigment proteins, under ultraviolet light. More information is available in the original publication.