Thread:S3r0-Ph1i/@comment-39117874-20190620230932/@comment-36009152-20190621215759

You are right they are all dinosaurs but the categorization is to help break them up in a certain way. You could add 'scaly' as a category to those of which they all are. If they were all red dinosaurs you could add 'red coloured' as a classification but adding them to 'Dinosaur', 'Scaly', or 'Red Coloured' categories are not likely helpful for the wiki, the required categories are used in a certain way.

In this case see the Dinosaur category and how it is being used? It covers further dinosuar genus groups and for the case of Tyrannosaurus the category leads to this category containing them all.