Question

Which type of jaw suspension is found in mammals?
1. Autostylic
2. Holostylic
3. Craniostylic
4. Hyostylic

Answer 1

Correct Answer - Option 3 : Craniostylic

Concept:

• Jaw suspension: The attachment of the lower jaw with the upper jaw or the skull which enables efficient biting & chewing of the food is called the jaw suspension
• The different types of jaw suspension found are Amphistylic, Autodiastylic, Hyostylic, Methystylic, Autostylic, Monimostylic, Holostylic & Craniostylic
• Craniostylic jaw suspension is found in the mammals

Explanation:

Craniostylic Jaw Suspension:

• This type of jaw suspension is primarily found in mammals.
• It is considered a modification of autostylic suspension
• The pterygoquadrate is changed into alisphenoid and incus, the Meckel's cartilage is transformed to form malleus and not available for jaw suspension. 
• In Craniostylic jaw suspension, the lower jaw fuses directly with the sull known as squamosal 
• It can also be observed in the Monotremes

  

Hyostylic	It is majorly seen in fishes The upper jaw is not directly attached to the cranium instead the upper is connected is with the cranium through a ligament at the front end and by the hyomandibular at the rear end.
Autostylic	In this type of suspension, the hypomandibular get transformed into columella and stapes of the middle ear for the conduction of sound waves The upper jaw get completely fused with its processes to the skull while the lower jaw remains suspended to the upper jaw
Holostylic	The upper jaw is fused with the skull and the lower jaw remains suspended to it. The hyoid arch is complete but does not participate in the jaw suspension i.e. it is independent and not attached to the skull Columella bone is absent