A  New Scientist article

suggests that the human ability to read actually cannibalizes parts of the brain used for other visual skills, such as tracking animals… and recognizing faces. Neurologists have long been faced with the “reading paradox” of how our brain contains such a specific area for reading while reading itself has only existed for 5000 years–far too short a time for the reading area of the brain to be an adaptive trait.

[Our] visual plasticity may have allowed for humans to “recycle” visual portions of the brain for reading, but not, his new study suggests, without a cost…

That cost is our ability to recognize faces.

Wait, who said that?

(via)