Question

A neopallium is found in the brain of
(a) Mammals
(b) Birds
(c) Reptiles
(d) frogs

Answer 1

Hint: The neocortex is a collection of layers of the mammalian cerebral cortex involved in higher-order brain functions such as sensory perception, comprehension, motor command generation, spatial thinking, and language, also known as the neopallium, isocortex, or the six-layered cortex.

Complete answer:
The neopallium has overgrown the other divisions of the cerebral cortex in mammals so that the paleopallium is entirely on the ventral surface of the cerebrum, ventral to the rhinal sulcus, and the archipallium as an internal gyrus, the hippocampus, is rolled medially into the lateral ventricle.
The neocortex is the major portion of the cerebral cortex of the human brain, and is the outer layer of the cerebrum, with the remainder making up the allocortex. The neocortex is composed of six layers, numbered I to VI from the outermost within. A species of oceanic dolphin known as the long-finned pilot whale has been found to have the most neocortical neurons of all the mammals studied to date (including humans).

Additional information: The neocortex is flat in rodents and other small mammals, although it has deep grooves (sulci) and ridges (gyri) in primates and other larger mammals. These folds make it possible to significantly increase the neocortex's surface region. All human brains have the same overall pattern of primary gyri and sulci, although they vary from one person to another in detail. It is not entirely clear the mechanism by which the gyri develop during embryogenesis, and there are many conflicting theories that explain gyrification, such as axonal stress, cortical buckling, or variations in cell proliferation rates in various cortex areas.
So, the correct answer is ‘(a) Mammals’.

Note: Embryonically, the neocortex is derived from the dorsal telencephalon, which is the forebrain's rostral portion. In regions demarcated by the cranial sutures in the skull above, the neocortex is divided into frontal, parietal, occipital, and temporal lobes that serve various functions.