In anatomy

Anatomy

Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...

 of animal

Animal

Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...

s, the archipallium is the oldest region of the brain's

Brain

The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...

 pallium

Pallium (neuroanatomy)

In a neuroanatomy context, the word pallium refers to the layers of gray and white matter that cover the upper surface of the telencephalon in vertebrates. The non-pallial part of the telencephalon builds the subpallium. In basal vertebrates the pallium is a relatively simple three-layered...

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The archipallium is often considered contiguous with the olfactory cortex

Piriform cortex

In anatomy of animals, the piriform cortex, or pyriform cortex is a region in the brain.-Anatomy and function:The piriform cortex is part of the rhinencephalon situated in the telencephalon....

, but the extent of the archipallium varies among species. In older species, such as fish, the archipallium makes up most of the cerebrum

Telencephalon

The cerebrum or telencephalon, together with the diencephalon, constitutes the forebrain. The cerebrum is the most anterior region of the vertebrate central nervous system. Telencephalon refers to the embryonic structure, from which the mature cerebrum develops...

. Amphibians develop an archipallium and paleopallium

Paleopallium

In anatomy of animals, the paleopallium is a region within the telencephalon in the brain.It is a primitive and evolutionarily ancient region of the brain, first appearing in amphibians....

, whereas reptiles develop an archipallium, paleopallium and a primitive neopallium.

In humans, the archipallium makes up the hippocampus

Hippocampus

The hippocampus is a major component of the brains of humans and other vertebrates. It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. Humans and other mammals have two hippocampi, one in...

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