ALA Booklist (Tue Dec 01 00:00:00 CST 2009)

As long as you can suspend all sense of evolution, literature, and good taste and are of a single-digit age, you'll crack up with hysterics at this theory of dinosaur extinction from the creators of Aliens Love Underpants (2007). According to the story, cavemen began to feel "embarrassed in the nude," and so they "dreamed up underpants," which the dinos coveted and copied, creating a mass frenzy that escalated into a Mighty Underpants War and the end of the giant beasts. Once again, the rhyming text and illustrations turn this into a comic delight.

Kirkus Reviews

The author and illustrator of Aliens Love Underpants (2007) go to the well again, describing in stumbling verse and colorful but unexceptional art how the dinos wiped themselves out squabbling over their prehistoric panties. Seeing cavemen modeling newly invented fur boxer shorts, the envious dinosaurs steal the concept, but they discover certain design flaws: "The pants from Woolly Mammoth coats / Made Stegosaurus itchy. / Diplodocus was really mad. / His briefs were way too pinchy!" Irritation quickly escalates into fury, and the ensuing autogenocide both leaves the cavemen (there are no women in evidence) relieved and leads to a closing "Don't forget briefs saved Mankind. / They're not just underwear!" Children may find Cort's cartoon pictures of big, grumpy-looking dinosaurs sporting undies loud with polka-dots and other patterns briefly (so to speak) amusing. (Picture book. 6-8)

School Library Journal (Fri Jan 01 00:00:00 CST 2010)

PreS Freedman and Cort offer another homage to underpants. Cartoons in bright colors and patterns pep up the rhymed tale that explains the demise of dinosaurs. According to Freedman, "When T. rex saw man's undies,/He roared with deafening rants./I don't want to eat you up./I want your underpants." All dinosaurs follow the obsessive fad, escalating to a manic dino tug-of-war that wipes out every order, saving mankind. Despite the skimpy plot, preschoolers will giggle as itchy or tight briefs annoy Stegosaurus or Diplodocus, while theft victim cavemen shyly cover up with huge leaves or the few remaining pairs of underwear. Gay Lynn Van Vleck, Henrico County Library, Glen Allen, VA