Answer
Yes, Gran stain is a useful tool for unterstanding the phylogeny of eurobacteria.
Explanation
The Gram staining method is used to classify two broad groups: gram-positive and gram-negative bacteria. This technique is widely used in clinical analysis and microbiology laboratories to monitor infections in pus smears or organic fluids.
In the Gran staining method, we subject the bacteria to dye treatments and, depending on the chemical composition of the cell wall of these bacteria, each one will react differently with the dyes and thus identify them by their biochemical characteristics.