#im sure this has been said before but its an obligatory el-im post. biology major lens watching ent.

[el-im]

another favorite thing about enterprise is giving the 5 distinct xindi species homologous structures to suggest common ancestry despite the fact that their lineage clearly divided them into separate species a long time ago. 

from what i can tell, there are at least three, as each intelligent species from xindus have 1. an upright invagination in the tissue of their cheeks (or equivalent region of their face) 2. at least three bony protrusions inferior to that, and 3. each display a series of fanning ridges between their eyes, with larger respective ridges superiorly

as demonstrated in the xindi arboreals

* the foreheads of the primates are frequently covered in long gray hairs, so this is an image which displays their cranial ridges a little more clearly

the xindi primates 

the xindi reptilians

the xindi insectoids 

*i think the insectoids are the best example of how these features change down the evolutionary pathway--what is represented as an invagination in flesh on the species descended from primates/reptilians/arboreal mammals/aquatic species is, in the insectoids, a tear-drop shaped opening. the basic shape remained the same, but the extra tissue has been discarded in favor of a lighter “design”, and the ‘bony’ protrusions, are likely an equivalent form of chitin, and are more pronounced in this species than in any of the others

and the xindi aquatics