Social structure of the bushveld sengi (Elephantulus intufi) in Namibia and the evolution of monogamy in the Macroscelidea

Abstract

The elephant-shrews or sengis (order Macroscelidea) represent a monophyletic radiation endemic to Africa with 15 extant species in four genera. Field studies of representatives from all four genera indicate that all are socially monogamous. Resource and female dispersion, indirect paternal investment and male mate guarding have been proposed as factors contributing to sengi monogamy. To better understand sengi social organization, we studied the behavioural ecology of the bushveld sengi Elephantulus intufi in Namibia. Radio-tags and direct observation were used to gather spatial and behavioural data during 5 months in [2000][2001][2002]. Bushveld sengis were distributed as monogamous pairs on exclusive territories, similar to other sengis. Maternal care was characterized by an 'absentee' strategy and there was no evidence of direct or indirect paternal care. Sengis share many life-history traits with small antelopes, including uni-parental monogamy. Unlike the antelopes, which exhibit strong pair bonds, bushveld sengi pairs spend little time in coordinated activities. Male mate guarding best explains why sengis are socially monogamous -a model largely developed from studies of small antelopes. The similarity in morphology, life history and behaviour among sengi species results in a distinctive adaptive syndrome, which explains the consistency of their social structure, even in the extremes of terrestrial habitats that they occupy. The degree of sengi social monogamy is labile, which is related to their weak pair bond, same-sex aggression and variable densities.

Meta‐analysis of the effects of small mammal disturbances on species diversity, richness and plant biomass

“…Based on the data set used on this study, it is clear that small mammals from Africa and Australia are particularly under-represented.These include, but are not limited to, elephant shrews (Rathbun & Rathbun 2006), porcupines (Dean & Milton 1991), Cape ground squirrels, meerkats (Waterman & Roth 2007), woylies (Claridge & May 1994;Garkaklis et al 2003Garkaklis et al , 2004, whistling rats (Jackson 2000), and mole rats (Whitford & Kay 1999). Based on the data set used on this study, it is clear that small mammals from Africa and Australia are particularly under-represented.These include, but are not limited to, elephant shrews (Rathbun & Rathbun 2006), porcupines (Dean & Milton 1991), Cape ground squirrels, meerkats (Waterman & Roth 2007), woylies (Claridge & May 1994;Garkaklis et al 2003Garkaklis et al , 2004, whistling rats (Jackson 2000), and mole rats (Whitford & Kay 1999).…”

Effects of life-history traits on parasitism in a monogamous mammal, the eastern rock sengi (Elephantulus myurus)

“…This order is endemic to Africa and encompasses 17 species belonging to four genera all of which are believed to be monogamous (Rathbun 1979 Schubert et al 2009a). The monogamous mating system of sengis is thought to be the result of male mate guarding and although attempts by males to include unmated females in their home range have been reported repeatedly, they were only of short duration (Rathbun 1979;Fitzgibbon 1997;Ribble and Perrin 2005;Rathbun and Rathbun 2006;Schubert et al 2009a). Sengis are known to carry a large number of ectoparasites, particularly ticks (e.g.…”

Abiotic and biotic determinants of tick burdens in the eastern rock sengi (Elephantulus myurus)

“…The entire order Macroscelidea is considered monogamous with a lack of sexual dimorphism and extensively overlapping home ranges among pairs (Rathbun, 1979; FitzGibbon, 1997; Rathbun & Rathbun, 2006; Schubert et al , 2009). In the present study, we focused on eastern rock sengis ( Elephantulus myurus Thomas & Schwann).…”