Temporal fenestrae

Definition

Temporal fenestrae are openings in the skull behind the eyes of some vertebrates. They serve to reduce the weight of the skull and provide attachment sites for muscles.

5 Must Know Facts For Your Next Test

1. Temporal fenestrae are crucial in differentiating between various groups of early amniotes.
2. There are three main types: anapsid (no fenestrae), synapsid (one fenestra), and diapsid (two fenestrae).
3. Diapsids include most modern reptiles and birds, while synapsids include mammals.
4. The presence and configuration of temporal fenestrae correlate with jaw muscle arrangement and feeding mechanics.
5. These openings evolved independently in different lineages as a response to similar selective pressures.

Review Questions

Related terms

Anapsid: A vertebrate whose skull has no temporal fenestrae, such as turtles.

Synapsid: A vertebrate whose skull has one temporal fenestra on each side, including mammals.

Diapsid: A vertebrate whose skull has two temporal fenestrae on each side, including most reptiles and birds.