title: The distribution, density and three-dimensional histomorphology of Pacinian corpuscles in the foot of the Asian elephant (Elephas maximus) and their potential role in seismic communication.
abstract: Both Asian (Elephas maximus) and African (Loxodonta africana) elephants produce low-frequency, high-amplitude rumbles that travel well through the ground as seismic waves, and field studies have shown that elephants may utilize these seismic signals as one form of communication. Unique elephant postures observed in field studies suggest that the elephants use their feet to 'listen' to these seismic signals, but the exact sensory mechanisms used by the elephant have never been characterized. The distribution, morphology and tissue density of Pacinian corpuscles, specialized mechanoreceptors, were studied in a forefoot and hindfoot of Asian elephants. Pacinian corpuscles were located in the dermis and distal digital cushion and were most densely localized to the anterior, posterior, medial and lateral region of each foot, with the highest numbers in the anterior region of the forefoot (52.19%) and the posterior region of the hindfoot (47.09%). Pacinian corpuscles were encapsulated, had a typical lamellar structure and were most often observed in large clusters. Three-dimensional reconstruction through serial sections of the dermis revealed that individual Pacinian corpuscles may be part of a cluster. By studying the distribution and density of these mechanoreceptors, we propose that Pacinian corpuscles are one possible anatomic mechanism used by elephants to detect seismic waves.
authors: Department of Comparative Medicine, Stanford University School of Medicine, Stanford, CA, USA. dbouley@stanford.edu
authors: D M
authors: DM
authors: Bouley
authors: C N
authors: CN
authors: Alarcón
authors: T
authors: T
authors: Hildebrandt
authors: C E
authors: CE
authors: O'Connell-Rodwell
mesh_terms: D000819:Animal Communication; D000818:Animals; D004606:Elephants / Q000502:physiology*; D005528:Foot / Q000033:anatomy & histology*; D005552:Forelimb; D006614:Hindlimb; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008465:Mechanoreceptors / Q000033:anatomy & histology*; D008867:Microtomy; D012677:Sensation / Q000502:physiology; D013016:Sound; D016474:Weight-Bearing
references: J Comp Physiol Psychol. 1982 Dec;96(6):926-44
references: 7153389
references: Am J Anat. 1976 Nov;147(3):329-55
references: 983972
references: J Anat. 1993 Aug;183 ( Pt 1):149-54
references: 8270469
references: Prog Neurobiol. 1994 Jan;42(1):79-128
references: 7480788
references: Anat Rec. 1996 Sep;246(1):127-34
references: 8876831
references: Eur J Morphol. 1996 Nov;34(4):311-20
references: 8982640
references: J Hand Surg Br. 1998 Jun;23(3):370-2
references: 9665528
references: J Acoust Soc Am. 1998 Aug;104(2 Pt 1):1122-3
references: 9714930
references: J Acoust Soc Am. 1999 Mar;105(3):2051-2
references: 10089624
references: J Neurophysiol. 1999 Apr;81(4):1548-58
references: 10200190
references: J Anat. 2006 Dec;209(6):781-92
references: 17118065
references: Anat Embryol (Berl). 1999 Dec;200(6):615-23
references: 10592065
references: J Comp Neurol. 2000 Feb 21;417(4):467-90
references: 10701867
references: J Acoust Soc Am. 2000 Dec;108(6):3066-72
references: 11144599
references: J Comp Neurol. 2002 Apr 15;445(4):347-59
references: 11920712
references: Anat Rec A Discov Mol Cell Evol Biol. 2004 Nov;281(1):1138-47
references: 15470674
references: J Neurophysiol. 1984 Apr;51(4):812-30
references: 6716125