That image is flawed.
Uruk-Hai were confirmed result of Inteligent Dasein [I knew I had seen that somewhere, Ford, but for all the powers of the universe couldn't remember where!]; it could be even accurately said that A Wizard Did It. More specifically, Sauron the Witch used Orcs as source material, and no one really has clear idea what the Orcs are - some claim they are corrupted Eldar; from this pool of genetic material Sauron created the first Uruks, and Saruman the White made them even harder, better, faster, stronger and resistant to sunlight as well, presumably by combining features from the race of Men or by some other magicks - he was most likely capable of great things as a Maia, even though his powers were not comparable to Sauron's.
On the other hand, the typical member of the Race of Men shown on the lower part of the image was the second race of [sentient] beings created by Eru Ilúvatar, the One God of cosmos and creator of Arda and all the Ainur and Valar. This process is largely hidden, but from the end results it's clearly apparent that Ilúvatar did better job.
Regardless, the argument completely fails because Men did not evolve from Uruk-Hai, and looting is a very common behaviour in almost all species that come upon a large, abandoned stash of goods, not to mention very common in war time with or without rules of engagement in place.
Furthermore, the date that the author gives for Uruk-Hai performing looting is completely unrealistic; by that time, all Uruk had been either extinct or in hiding for a long time, and no reports of them are in historic records from that time.
So you see, I verily suspect the credibility of this claim that looting has evolved, and even more so the evolution of looters.
