There is not much to eat in the coniferous forest compared with the food available in other parts of the world. Hence there are fewer types of vertebrae animals here, and each type is very highly adapted for its particular lifestyle. Nowhere is this more evident than in the case of the jinx. The jinx eats coneaters, and nothing else. Its whole physiology has developed to aid this. Since the Cretaceous period, the most successful medium-sized carnivorous dinosaurs have been the dromaeosaurs and the troodontids. These are generally lightly built bipedal animals, about 3 meters long (10 feet), with long, stiff tails, which means they resemble hypsilophodonts in bodily shape. There are differences, of course, especially in the teeth and claws. Both the troodontids and dromaeosaurs have a large killing claw on the second toe, obliging them to walk on only their third and fourth toes. This is quite different from the three-toed arrangement of the feet of the hypsilophodonts. The long mouth conceals a battery of meat-shearing teeth. They have grasping hands but with only three fingers, compared with the five of the plant-eaters. The meat-eaters also lack the characteristic pot belly of the browsers. Nevertheless, the superficial resemblance is so close that one dromaeosaur, the jinx, has adopted a coloration that disguises it as a hypsilophodont and allows it to infiltrate the coneater herds. The deception is so successful that a herd of coneaters may travel for quite some distance without noticing the danger in its midst.