The comparative feeding mechanism of gadidae and macrouridae. I. Functional morphology of the feeding apparatus.

The comparative feeding apparatus of Gadidae and Macrouridae has been studied from a functional point of view. Some important modifications in macrourid species in comparison with the gadid ones were found: rostral end of the cranium, rostral ligaments and disposition of the jaw muscles. Anyways, all the modifications seem secondary, motivated by the habitat. That is true in the case of the beak, in relation with the swimming system which had been already observed by Marshall and Bourne (1964). The question of the rostral ligaments modification would be related with the protraction of the upper jaw, but a further analysis is required. Also discussed are two schemes of possible changes in the jaw musculature.