Question

Skull of birds is
a. Monocondylic
b. Dicondylic
c. Amphicondylic
d. Acondylic

Answer 1

Hint: The anatomy of birds is different, and unique where the modifications occur in such a way, in order to adapt for flying, and the bones of birds are lightweight and the musculature is very strong, and this is also an adaptation to flying.

Complete answer:
Mainly birds consist of 5 bones, which are
Frontal bone on the top of the head,
Parietal bone on the back of the head,
Premaxillary and Nasal bones at the top of the beak, and
Mandible bottom beak.

- The skull of the body is very lightweight and it occupies only 1% of its total body weight.
- Birds' skulls consist of small overlapping bones which are called Pedomorphosis.
- The skull of birds has so many changes from the ancestors, this is mainly due to unique flight nature and their feeding habits.
- The palatial structure of the bones is reduced more, where pterygoid, Palatine, and jugular bone are reduced.
- The premaxillary bone is hypertrophied to form the beak, while Maxilla is reduced.
- Premaxilla plays a vital role in the case of feeding.
- The skull bones of the bird are able to show the independent movements which are known as cranial kinesis, and this cranial kinesis occurs in several forms.
- Birds have a diapsid skull, which is seen in reptiles also.
- Birds contain only one condyle that is the occipital condyle, so birds are said to be Monocondylic.

Hence, the correct answer is option (A).

Note: Skull of the birds is monocondylic, and they can rotate up to 270 degrees, and the mammals and amphibians have dicondylic skulls, which means that they have two condyles, and some animals may be amphicondylic.