Intraspecific Allometric comparison of Laboratory gerbils with Mongolian Gerbils Trapped in the Wild Indicates Domestication in Meriones unguiculatus (Milne-Edwards, 1867) (Rodentia: Gerbillinae)

• Published in: Zoologischer Anzeiger Vol. 242; no. 3; pp. 249 - 266
• Main Authors: Stuermer, Ingo W., Plotz, Karsten, Leybold, Axel, Zinke, Olaf, Kalberlah, Otto, Samjaa, Ravchikh, Scheich, Henning
• Format: Journal Article
• Language: English
• Published: Elsevier GmbH 2003
• Subjects: Allometry; brain size reduction; enriched environment; epileptic seizures; reproduction; enriched environment; Allometry; epileptic seizures; brain size reduction; reproduction
• ISSN: 0044-5231; 1873-2674
• DOI: 10.1078/0044-5231-00102

A survey of adult male Mongolian gerbils, Meriones unguiculatus (Milne-Edwards, 1867), either trapped during an expedition in Mongolia near 47 °N and 105,5 °E in June 1995 (WILD) or obtained from a laboratory strain bred in captivity since 1935 (LAB), revealed significant morphological and behavioural differences, which are likely a result of domestication in the laboratory strain. Mean body length (125.4 mm), tail length (95.5 mm) and body weight (53.6 g) was lower in WILD, although no other external characteristics were obviously different. Related allometrically to net carcass weight, organ weights were significantly lower (p < 0.01) in LAB (brain – 17.6%, eyes – 26.0%, heart – 22.3%, lungs – 43.3%). Seizures frequently seen in LAB were absent in WILD trapped (n = 167) or subsequently housed in Germany (n = 81), and rare in their offspring. Mean litter size was greater in LAB (n = 5.5) than in WILD bred in the laboratory (n = 4.4). The WILD breeding strain was named Ugoe:MU95. A genetic bottleneck (n = 9) that occurred in 1954 and remarkably smaller brains in LAB indicate that the laboratory strain has become domesticated and should be designated as “Laboratory gerbils” ( M. unguiculatus forma domestica) to signify this new case of domestication among rodents.