Question

Mammal like reptiles belong to
(a)Anapsid line of evolution
(b)Euryapsid line of evolution
(c)Parapsid line of evolution
(d)Synapsid line of evolution

Answer 1

Hint: In classical systematics, mammal-like reptiles belong to non-mammalian lineages. These are a group of animals that are more closely related to mammals than the members of the amniote clade, such as reptiles and birds.

Complete answer:
-The members of synapsid are separated from other amniotes for having temporal fenestra which is an opening low in the skull roof behind each eye, leaving a bony arch beneath each.
-The primitive synapsids are usually called pelycosaurs or pelycosaur-grade synapsids.
-These organisms are now correctly referred to as stem mammals or proto-mammals.
-The distinctive temporal fenestra developed in these organisms during ancestral synapsid (Late Carboniferous period) about 312 million years ago.

Additional Information: -Synapsids used to be the largest terrestrial vertebrates in the Permian period about 251 million years ago.
-The synapsids are divided into a primitive group and an advanced group, known as pelycosaurs and therapsids respectively.
-Pelycosaurs consist of the six most primitive families of synapsids. They all were rather lizard-like, with sprawling gait and possibly horny scutes.
-The therapsids consist of the more advanced synapsids, having a more erect pose and hair, in few forms.
-In classical taxonomy, the Synapsida comprises two distinct grades successively closer to mammals: the low-slung pelycosaurs have risen to the more erect therapsids, who in their turn gave rise to the mammals.
So, the correct answer is ‘Synapsida line of evolution’

Note: -Synapsids had differentiated teeth such as the canines, molars, and incisors.
-Synapsids have evolved from basal amniotes and are one of the two major groups of amniotes.