Brain Structure and Function

, Volume 223, Issue 3, pp 1191–1216 | Cite as

Nuclear organization of the African elephant (Loxodonta africana) amygdaloid complex: an unusual mammalian amygdala

  • Aude’Marie Limacher-Burrell
  • Adhil Bhagwandin
  • Busisiwe C. Maseko
  • Paul R. Manger
Original Article


Here we describe the nuclear organization of the African elephant amygdaloid complex using Nissl, myelin, and a range of immunohistochemical stains. The African elephant is thought to exhibit many affect-laden and social-empathic behaviours; however, to date the amygdaloid complex, which is the generator of emotional states of the brain is yet to be fully explored in the elephants. For the most part, the amygdaloid complex of the African elephant is similar to that observed in other mammals in terms of the presence of nuclei and their topological relationships; however, we did observe several specific differences in amygdaloid organization. The elephant amygdala has undergone rotation in both the coronal and sagittal planes, seemingly associated with the expansion of the temporal lobe. Numerous scalloped cell clusters, termed glomeruli, forming the intermediate nuclei of the basal, accessory basal and central nuclear groups, were occupied by structures immunopositive to doublecortin. The nuclei typically associated with the accessory olfactory system (posterior cortical nucleus and medial nuclear complex) were absent from the elephant amygdala. The anterior cortical nucleus is very large and appears to be comprised of two subdivisions. The lateral nuclear complex is expanded and has two novel subdivisions. The amygdalohippocampal area appears relatively enlarged. The numerous shared and derived characters make the elephant amygdaloid complex very unusual and unique amongst mammals, but the derived characters appear to relate to observed elephant affect-laden behaviours.


Amygdala Afrotheria Social-empathic behaviour Emotion Mammalia Cognition 



Accessory basal nucleus, intermediate division


Accessory basal nucleus, magnocellular division


Accessory basal nucleus, parvocellular division


Accessory basal nucleus, shell


Amygdalohippocampal area


Basal nucleus, magnocellular division


Basal nucleus, intermediate division


Basal nucleus, parvocellular division


Cornu ammonis region 1 of hippocampus


Cornu ammonis region 3 of hippocampus


Central amygdaloid nucleus, capsular division


Central amygdaloid nucleus, intermediate division


Central amygdaloid nucleus, lateral division


Central amygdaloid nucleus, medial division


Anterior cortical amygdaloid nucleus, dorsal division


Anterior cortical amygdaloid nucleus, ventral division


Dentate gyrus of hippocampus




Intercalated island of the amygdala


Internal capsule


Amygdaloid intramedullary gray matter


Lateral amygdaloid nucleus, dorsolateral part


Lateral amygdaloid nucleus, medial part


Lateral amygdaloid nucleus, ventrolateral part


Lateral ventricle




Periamygdaloid cortex, lateral division


Periamygdaloid cortex, medial division


Piriform cortex





This work was supported by funding from the South African National Research Foundation (BCM and PRM). We thank the relevant wildlife authorities for permission to collect the material used.

Compliance with ethical standards

Conflict of interest

All authors declare no conflict of interest.

Ethical statement

The brains of two African elephants (Loxodonta africana) were used for the purpose of this study. The specimens were obtained in Zimbabwe under the permission of the Zimbabwe Parks and Wildlife Management Authority as well as the Malilangwe Nature Conservation Trust (specimen preparation, treatment and storage described in Manger et al. 2009). The animals were treated and used according to the guidelines of the University of the Witwatersrand Animal Ethics Committee (Clearance number: 2008/36/1).


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Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  • Aude’Marie Limacher-Burrell
    • 1
  • Adhil Bhagwandin
    • 1
  • Busisiwe C. Maseko
    • 1
  • Paul R. Manger
    • 1
  1. 1.School of Anatomical SciencesUniversity of the WitwatersrandJohannesburgSouth Africa

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