Word for giving animal characteristics (esp. physical ones) to humans

You can probably get some mileage out of 'zoomorphism':

2. Use of animal forms in symbolism, literature, or graphic representation.

The primary sense is, however,

1. Attribution of animal characteristics or qualities to a god.

(From zoomorphism. (n.d.) American Heritage® Dictionary of the English Language, Fifth Edition. (2011). Retrieved September 24 2015 from http://www.thefreedictionary.com/zoomorphism.)

Theriomorphism, an alternative to "zoomorphism", is defined as the shaping of something or someone (often a divinity) in the form of an animal.

From Greek: "thērion" (diminutive of thēr, i.e. wild beast) and "morphe" (form, shape).

If you prefer a more understandable word, one may say animalisation that is a depiction in the form of an animal.