Sentence:  In the lowest orders of being, we find these functions very much blended together, and several of them apparently performed by one simple apparatus ; but in proportion as we rise in the scale, we perceive that they are <WSD>specialized,</WSD> or separated from each other, and that a complicated set of organs is appropriated to each of them. 
Meaning of the word marked with <WSD> tags:  To make distinct or separate in form or function.