title: Properties and architecture of the sperm whale skull amphitheatre.
abstract: The sperm whale skull amphitheatre cradles an enormous two-tonne spermaceti organ. The amphitheatre separates this organ from the cranium and the cervical vertebrae that lie in close proximity to the base of the skull. Here, we elucidate that this skull amphitheatre is an elastic, flexible, triple-layered structure with mechanical properties that are conjointly guided by bone histology and the characteristics of pore space. We contend that the amphitheatre will flex elastically to equilibrate forces transmitted via the spermaceti organ that arise through diving. We find that collisions from sperm whale aggression do not cause the amphitheatre to bend, but rather localise stress to the base of the amphitheatre on its anterior face. We consider, therefore, that the uniquely thin and extended construction of the amphitheatre, has relevance as an energy absorptive structure in diving.
authors.affiliation: Laboratory of Paper Coating and Converting, Centre for Functional Materials, Abo Akademi University, Porthaninkatu 3, 20500 Turku, Finland. Electronic address: parvez.alam@abo.fi.
authors.forename: Parvez
authors.initials: P
authors.lastname: Alam
authors.affiliation: Biological and Biomimetic Materials Laboratory, School of Materials Science and Engineering, 50 Nangang Avenue, Nanyang Technological University, Singapore.
authors.forename: Shahrouz
authors.initials: S
authors.lastname: Amini
authors.affiliation: Biological and Biomimetic Materials Laboratory, School of Materials Science and Engineering, 50 Nangang Avenue, Nanyang Technological University, Singapore.
authors.forename: Maryam
authors.initials: M
authors.lastname: Tadayon
authors.affiliation: Biological and Biomimetic Materials Laboratory, School of Materials Science and Engineering, 50 Nangang Avenue, Nanyang Technological University, Singapore.
authors.forename: Ali
authors.initials: A
authors.lastname: Miserez
authors.affiliation: Department of Biological Sciences, University of Cape Town, South Africa.
authors.forename: Anusuya
authors.initials: A
authors.lastname: Chinsamy
mesh_terms: D000818:Animals; D004242:Diving / Q000502:physiology; D005147:Facial Bones / Q000033:anatomy & histology / Q000648:ultrastructure; D012886:Skull / Q000033:anatomy & histology* / Q000502:physiology / Q000648:ultrastructure; D050661:Sperm Whale / Q000033:anatomy & histology* / Q000502:physiology; D013314:Stress, Mechanical
keywords: Cetacea; Physeter macrocephalus; Sperm whale; Spermaceti organ; Whale skull