Is it acceptable to change the appearance of global site navigation elements based on where you are in the site? Let me give you an example. (This example is completely made up, but accurately represents the amount/depth of content -- and pretend your "market" here is people who typically are interested in one animal and are not frequently looking at other animals.)
In this example, someone is looking for squirrels. They click mammals, then click squirrels in the dropdown, and are then taken to a squirrel-related page which has two levels of navigation to it.
Please note that due to the sheer volume of content, it is not feasible to collapse this to fewer levels of navigation.
Is this jarring? Have others seen this elsewhere used well? My goal with this to focus the navigation on the content the user needs at that time. (I have asked a couple other similar questions on here recently but figured it would be best to show a potential fix to get any thoughts/reactions.)