Synapsida

Thân thiện

Definition

Noun * Synapsida: A major subclass or clade of amniote vertebrates, traditionally classified as an order, characterized by having a single temporal fenestra (opening) behind each eye socket in the skull. This group includes extinct "mammal-like reptiles" and all of their descendants, which are the mammals. They are distinguished from other amniotes like diapsids (reptiles, birds) and anapsids.

Usage

• The term is used in scientific, paleontological, and evolutionary biological contexts to classify a key lineage in the evolution of vertebrates from reptiles to mammals.
• It is a taxonomic name and is typically capitalized.

Examples

• Noun:
  • Fossil evidence shows that Synapsida was a dominant terrestrial group during the Permian period.
  • The transition from early Synapsida to true mammals occurred over millions of years.
  • Pelycosaurs and therapsids are successive branches within the Synapsida.

Advanced Usage

• In modern cladistics (evolutionary classification), Synapsida is often not considered "reptiles" in the strict sense but is part of a larger group (Sauropsida) that includes all amniotes more closely related to modern reptiles than to mammals. However, the traditional description as "mammal-like reptiles" remains common in general usage.
• The defining single temporal opening is a synapsid skull structure.

Variants and Related Words

• Synapsid (noun): Any member of the clade Synapsida. (e.g., )
• Synapsid (adjective): Of or relating to the Synapsida. (e.g., )

Synonyms

• Theropsida (an alternative, less common taxonomic name for a similar grouping).
• Mammal-like reptiles (a descriptive, paraphyletic term for the non-mammalian members of Synapsida).

Different Meanings

This word has a single, specific scientific meaning in taxonomy and evolutionary biology. It does not have common everyday meanings or idioms.

Học thuật

Noun

1. extinct reptiles of the Permian to Jurassic considered ancestral to mammals

Từ đồng nghĩa

• Synapsida
• subclass Synapsida