synapsid

American  

[si-nap-sid] / sɪˈnap sɪd /

noun

plural

synapsids

1. any of a subclass Synapsida including mammals and their extinct relatives and having one temporal opening on each side of the skull.

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synapsid Scientific  

/ sĭ-năp′sĭd /

1. Any of various amniotes with one temporal opening on each side of the skull. Synapsids emerged in the late Permian Period and were characterized by carrying their limbs under their body and developing front teeth that were different from their back teeth. One group of synapsids, the therapsids, gave rise to the mammals.

2. Compare anapsid diapsid therapsid

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Example Sentences

This finding provides important context for a key step in synapsid evolution.

From Science Daily • Feb. 22, 2024

They found a major shift in synapsid jaw function roughly 270 million years ago linked to a significant shift in predatory behaviour that has important implications for the evolution of our earliest ancestors.

From Science Daily • Feb. 22, 2024

Julius and I endeavored to surprise and delight readers with our interpretation of how this giant synapsid might have looked walking through Late Triassic–era Poland.

From Science Magazine • Jan. 10, 2020

An early synapsid with extensive soft tissue preservation.

From Scientific American • Jul. 23, 2017

In the course of synapsid evolution leading to mammals, the temporal presumably became the main muscle mass acting in adduction of the lower jaw.

From The Adductor Muscles of the Jaw In Some Primitive Reptiles by Fox, Richard C.