Quetzalcoatlus northropi- BIO203
Feeding/Nutrition
Not
only are scientists interested in the flight mechanisms of a pterosaur,
but also their feeding habits are quite misunderstood. At first, many
researchers proposed that pterosaurs evolved into being skim feeders
(Humphries 2007). This type of feeding refers to the act of flying very
low over a body of water with your mouth open, and filtering your prey
into the individuals’ mouth. This method was proposed because of the
morphology of the pterosaurs jaw, headcrest, and neck. According to
fossils found of Quetzalcoatlus northropi, this creature possessed a
lower jaw or mandible that pointed downward and lacked teeth (Humphries,
2007). To aid in this pterosaurs had a head crest , which is a ridge
like projection on the head, that anchored the forces resisted by the
muscles, and a long neck that was useful for skimming at shallow depths
(Humphries, 2007). All these characteristics evolved to be advantageous
in this reptiles’ way of feeding. Most people accepted this, but some
also rejected. Some say that there is no way that the pterosaur had
enough power and flight capability to skim feed as their only means of
collecting food. Also, researchers have pointed out that a pterosaur was
indeed, able to catch food from skim feeding, but they lacked teeth and
a hooked jaw to capture or grasp the food once they caugh
t it while in
flight (Humphries, 2007). Not only did the jaw implication cause
problems, but the shape of the neck also would have created the issue of
deflecting water away from the mouth instead of water and prey flowing
freely into the pterosaurs mouth (Humphries, 2007). Due to all these
costs of skim feeding, another hypothesis of feeding was introduced.
This type of feeding resembled the feeding of other carnivorous
terrestrial animals by hunting small game on land. Pterosaurs have
adapted to life on land by having very long fore and hind limbs for
running and catching prey (Humphries, 2007). Also they have a long neck
that would be beneficial in stalking and catching prey (Humphries,
2007). Figure 1 shows a pterosaur using the stalking method of feeding. Whether, pterosaurs hunted on land or skim fed, they definitely
evolved advantageous adaptions to conquer each method at ease.