Changes

*All species have ''Frontal'' and ''Maxillary'' systems

*All species have ''Frontal'' and ''Maxillary'' systems

**''Frontal'': consists of space(s) within the bones between the cranial cavity and the [[Nasal cavity - Anatomy & Physiology|nasal cavity]].

**''Frontal'': consists of space(s) within the bones between the cranial cavity and the [[Nasal cavity - Anatomy & Physiology|nasal cavity]].

**''Maxillary'': this is the largest sinus, and consists of the space within the caudolateral part of the upper jaw, above the caudal cheek [[Oral Cavity - Teeth & Gingiva - Anatomy & Physiology|teeth]]. This increases with age due to wearing and ventral relocation of the [[Oral Cavity - Teeth & Gingiva - Anatomy & Physiology|teeth]].

**''Maxillary'': this is the largest sinus, and consists of the space within the caudolateral part of the upper jaw, above the caudal cheek [[:Category:Teeth - Anatomy & Physiology|teeth]]. This increases with age due to wearing and ventral relocation of the [[:Category:Teeth - Anatomy & Physiology|teeth]].

==Function==

==Function==

*Limiting the weight of the [[Skull and Facial Muscles - Anatomy & Physiology#Bones of the Skull|skull]].

*Limiting the weight of the [[Skull and Facial Muscles - Anatomy & Physiology#Bones of the Skull|skull]].

*Insulation/Cooling of the [[Nervous and Special Senses - Anatomy & Physiology#Central Nervous System (CNS)|brain]].

*Insulation/Cooling of the [[Nervous and Special Senses - Anatomy & Physiology#Central Nervous System (CNS)|brain]].

*Increased insertion space for [[Oral Cavity - Teeth & Gingiva - Anatomy & Physiology|teeth]].

*Increased insertion space for [[:Category:Teeth - Anatomy & Physiology|teeth]].

==Species Differences==

==Species Differences==