Ecological constraints drive social evolution in the African mole-rats.
Proc Biol Sci
; 264(1388): 1619-27, 1997 Nov 22.
Article
in En
| MEDLINE
| ID: mdl-9404025
ABSTRACT
The African mole-rats (family Bathyergidae) are subterranean hystricomorph rodents occurring in a variety of habitats and displaying levels of sociality which range from solitary to eusocial, making them a unique mammalian taxonomic group to test ecological influences on sociality. Here, we use an extensive DNA-based phylogeny and comparative analysis to investigate the relationship between ecology, sociality and evolution within the family. Mitochondrial cytochrome-b and 12s rRNA trees reveal that the solitary species are monophyletic when compared to the social species. The naked mole-rat (Heterocephalus glaber) is ancestral and divergent from the Damaraland mole-rat (Cryptomys damarensis), supporting previous findings that have suggested the multiple evolution of eusociality within the family. The Cryptomys genus is species-rich and contains taxa exhibiting different levels of sociality, which can be divided into two distinct clades. A total of seven independent comparisons were generated within the phylogeny, and three ecological variables were significantly correlated with social group size geophyte density (p < 0.05), mean months per year of rainfall greater than 25 mm (p < 0.001), and the coefficient of rainfall variation (p = 0.001). These results support the food-aridity hypothesis for the evolution of highly social cooperative behaviour in the Bathyergidae, and are consistent with the current theoretical framework for skew theory.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Social Behavior
/
Mole Rats
/
Ecology
/
Biological Evolution
Aspects:
Determinantes_sociais_saude
Limits:
Animals
/
Humans
Country/Region as subject:
Africa
Language:
En
Journal:
Proc Biol Sci
Journal subject:
BIOLOGIA
Year:
1997
Document type:
Article
Affiliation country:
United kingdom