The helicis major (or large muscle of helix) is an intrinsic muscle of the

outer ear The outer ear, external ear, or auris externa is the external part of the ear, which consists of the auricle (also pinna) and the ear canal. It gathers sound energy and focuses it on the eardrum (tympanic membrane). Structure Auricle Th ...

. In human anatomy, it is the form of a narrow vertical band situated upon the anterior margin of the

helix A helix () is a shape like a corkscrew or spiral staircase. It is a type of smooth space curve with tangent lines at a constant angle to a fixed axis. Helices are important in biology, as the DNA molecule is formed as two intertwined helic ...

, at the point where the helix becomes transverse. It arises below, from the

spina helicis At the front part of the auricula, where the helix bends upward, is a small projection of cartilage Cartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as ar ...

, and is inserted into the anterior border of the helix, just where it is about to curve backward. The function of the muscle is to adjust the shape of the

ear An ear is the organ that enables hearing and, in mammals, body balance using the vestibular system. In mammals, the ear is usually described as having three parts—the outer ear, the middle ear and the inner ear. The outer ear consists of ...

by depressing the anterior margin of the ear cartilage. While the muscle modifies the auricular shape only minimally in the majority of individuals, this action could increase the opening into the

external acoustic meatus The ear canal (external acoustic meatus, external auditory meatus, EAM) is a pathway running from the outer ear to the middle ear. The adult human ear canal extends from the pinna to the eardrum and is about in length and in diameter. Struct ...

in some. The helicis major is developmentally derived from the second

pharyngeal arch The pharyngeal arches, also known as visceral arches'','' are structures seen in the embryonic development of vertebrates that are recognisable precursors for many structures. In fish, the arches are known as the branchial arches, or gill arche ...

. It seem that only in primates is the

helicis minor The Helicis minor (musculus helicis minor or smaller muscle of helix) is a small skeletal muscle. The helicis minor is an intrinsic muscle of the outer ear. The muscle runs obliques and covers the helical crus, part of the helix located just abo ...

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