With regards to the following passage in the introductory paragraph, "The project largely uses hardy cattle breeds with optic resemblance to the extinct aurochs" 
 Does optic resemblance mean a superficial (i.e. outwardly physical) resemblance? That's a strange way of writing it. If it means something else within the field of work related to TaurOs, is there an explanatory article elsewhere which can shed light on this phrase?