Traditionally, these trees have been built using morphological methods, such as appearance, embryology, etc. Recently, it has been possible to construct these trees using molecular data, based on similarities and differences between genetic and protein sequences.
Tradicionalmente, estas árbores construíanse usando modelos morfolóxicos, como a aparencia, embrioloxía etc. Modernamente, foi posible construílos usando datos moleculares, baseados en semellanzas e diferenzas entre secuencias xenéticas e proteicas.