Cladistic taxonomists prioritize shared derived characters, which are traits that evolved in the common ancestor of a group and are passed down to its descendants. They use these characters to construct cladograms, which are tree-like diagrams that show the evolutionary relationships between organisms.

Here's a breakdown of what cladistic taxonomists do and don't compare:

Cladistic Taxonomists Compare:

* Shared derived characters: These are the most important for cladistic analysis. They indicate a close evolutionary relationship.

* Shared ancestral characters: These are traits that were present in a distant common ancestor. While they help establish a broader evolutionary context, they are less informative for determining specific relationships within a group.

Cladistic Taxonomists Do Not Compare:

* Overall similarity: Cladistics focuses on shared derived characters, not overall resemblance. Two organisms might share many superficial features without being closely related.

* Analogous structures: These are structures that have similar functions but different evolutionary origins. For example, the wings of a bat and the wings of a bird are analogous structures.

* Developmental patterns: While developmental data can provide insights, cladistics primarily relies on shared derived characters.

In summary: Cladistic taxonomists focus on shared derived characters to understand evolutionary relationships, rather than overall similarity, analogous structures, or developmental patterns.