Table 1.

Natural (field) behavior of a small sampling of well-studied rodents that exhibit diverse and interesting social behaviors.

Genus/species	Group size/composition	Mating system/social relationships	Home range/dispersal	Other features	References
Naked mole-rats	Dominant breeding female and up to a few breeding males Closely related conspecifics that help care for young, forage, maintain nest/tunnels, defend against predators Specific caste/body size associated with each worker role Live in large colonies of 200–300 individuals, with a mean group size of ~80 Litters of up to 28 offspring	Eusociality Monogamy/polyandry Highly inbred Non-breeding adults reproductively suppressed Reproductive suppression reversible and maintained by aggression/threats from dominant female	Successful dispersal infrequent Subordinate adults usually remain in natal nest	Arguably most social of all rodents Related species with varying degrees of sociality	(Faulkes & Bennett, 2007; Jarvis, 1981; Lacey & Sherman, 1991; Nowak, 1999; Sherman et al., 1991)
Black-tailed prairie dogs	Live in large colonies (towns) made up of coteries (family groups) Coteries generally consist of 1–2 adult males, 1–6 adult females, and offspring One colony may contain 15–26 coteries	Polygyny Little or no multiple mating by females, even if other males available Communal nesting with close female relatives Mothers nurse communally after juveniles from different litters begin to share burrows	Delay in dispersal and reproduction compared to more solitary prairie dog species Coterie territory boundaries well-defined and defended Females generally remain in natal coterie Males disperse to other coteries within the same colony Males and females sometimes disperse outside of colony	Known for alarm calls, specific to species and approach of predators	(Foltz & Hoogland, 1981; Hoogland, 1982, 1983, 1985, 2007, 2013; Michener & Murie, 1983; Nowak, 1999)
Beavers	Pair-bonded male and female breeding pair and their offspring Older family members may live with family group	Social and sexual monogamy Bi-parental care Long-lasting pair bonds Degree of social interaction inversely related to age	Territory defense Territory marking (scent mounds) Older family members may be juveniles delaying dispersal	Construct lodges and dams from mud and sticks	(Busher, 2007; Godin, 1977; Jenkins & Busher, 1979; Nowak, 1999; Wilsson 1971)
Belding’s ground squirrels	Female and her offspring	Non-defense polygyny Multiple paternity of litters common (promiscuity rather than true polygyny) Dominance hierarchies determine male reproductive success No mate guarding (clear first male advantage) Mothers and daughters cooperate to defend against infanticide Antipredator warning calls—females display nepotistic behavior	All males disperse from natal nest Mothers and daughters set up territories near each other	Most comprehensive data on rodent sociality exists for ground-dwelling squirrels (which include prairie dogs, marmots, chipmunks, and ground squirrels) Kin/social recognition important Long social memory	(Hanken & Sherman, 1981; Hare & Murie, 2007; Mateo, 2010; Nowak, 1999; Sherman, 1981, 1985; Sherman & Morton, 1984)
Prairie voles	Male-female pair and their offspring Shift toward communal groups in fall/winter, but less pronounced change than in meadow voles	Social but not sexual monogamy Bi-parental care Mate-guarding by males Alloparental care by older siblings Exhibits specific preferences for known peers and mates	Male-female pairs have overlapping home ranges that they defend	Most well studied of vole species, and extensively studied in the lab	(Carter & Getz, 1993; Getz, McGuire, Pizzuto, Hofmann, & Frase, 1993; Getz, 1962, 1972; Getz & Carter, 1996; Ophir, Phelps, Sorin, & Wolff, 2007; Solomon & Jacquot, 2002; Thomas & Birney, 1979)
Meadow voles	Breeding female dyads in spring Solitary in summer Maternal family group, and some adult and subadult males in fall Mixed-lineage social group in winter	Promiscuous Intolerant toward conspecifics during breeding season Nests in groups and shares territories during non-breeding season Exhibits specific preferences for known peers	Females defend territories during breeding season Home ranges overlap increasingly through fall/winter Males disperse from natal nest	Seasonal sociality	(Boonstra, Xia, & Pavone, 1993; Dark, Zucker, & Wade, 1983; Ferkin, 1988; Madison, 1980; Madison, FitzGerald, & McShea, 1984; Madison & McShea, 1987; McShea & Madison, 1984; Turner, Iverson, & Severson, 1983)
Mice (Lab)	Large hierarchical group Territorial groups (demes) founded by one male and multiple females	Social hierarchy Polygyny Interactions between males relatively rare and usually aggressive	Less complex burrows than rats (often contain a single cavity occupied by a single male) Males territorial Highly variable home ranges (and population densities) based on food availability and other related factors	One of the most well studied lab animals Many genetic techniques exist for mice that do not exist for most (if not all) other species Spontaneously form stable dominance hierarchies in the lab Environmental richness an important factor in determining features of their group living	(Bronson, 1979; Lidicker, 1976; Lloyd, 1975; MacKintosh, 1973; Nowak, 1999; Poole & Morgan, 1973, 1976; Schmid-Holmes, Drickamer, Robinson, & Gillie, 2001; Zegeren, 1979)
Rats (Lab)	Large hierarchical group (colony)	Social hierarchy, but less absolute than in mice Polygynandry, with all males mating but dominant male mating the most	Less territorial than mice Highly variable home ranges (and population densities) based on food availability, etc.	One of the most well studied lab animals Ideal for studying mechanisms of mothering due to well-defined suite of maternal behaviors Also studied for their gregariousness and pro-sociality Environmental richness an important factor in determining features of their group living	(Berdoy & Drickamer, 2007; Calhoun, 1948, 1962; MacDonald, Mathews, & Berdoy, 1999; McClintock & Anisko, 1982; McClintock, Anisko, & Adler, 1982; Nowak, 1999)
California mice	Small, semi-permanent family groups	Social and sexual monogamy Bi-parental care Fathers display all parental behaviors beside nursing as much as mothers	Mated pairs have largely overlapping home ranges	Studied for their paternal care and winner effect	(Bedford & Hoekstra, 2015; Gubernick & Alberts, 1987; Gubernick & Nordby, 1993; Nowak, 1999; Ribble, 1992; Ribble & Salvioni, 1990)
Social tuco-tuco	Social species in a clade with many solitary and a few other social species for comparisons Variation in group size and composition Up to 6 closely related adult females, at most one immigrant adult male, and dependent young	All females reproduce Communal nesting Male and females contribute to care of young	2/3 of females remain in natal burrows All males disperse after becoming adults and after each breeding season	Allonursing observed in lab Cooperative behaviors: digging, alarm calling	(Lacey, 2004; Lacey, Braude, & Wieczorek, 1997, 1998; Lacey & Wieczorek, 2004; Tammone, Lacey, & Relva, 2013)
Degus	Colonial 2–5 females and dependent young Number of adult males unclear (single or multiple)	All females reproduce Communal nesting Male(s) and females contribute to care of young	High turnover rate of group members No sex bias in dispersal	Allonursing observed in lab Cooperative behaviors: digging, alarm calling	(Ardiles et al., 2013; Colonnello, Iacobucci, Fuchs, Newberry, & Panksepp, 2011; Ebensperger, Chesh, et al., 2011; Ebensperger, Ramírez-Estrada, et al., 2011; Ebensperger, Hurtado, Soto-Gamboa, Lacey, & Chang, 2004; Fulk, 1976)
Striped mice	Facultative sociality Social populations: Up to 30 adult individuals (2–4 breeding females, 1 breeding male, adult offspring)	Social populations: Communal breeding, philopatric young Solitary populations: Males and females only interact to mate	Social populations: Territorial social groups, males mostly patrol borders Solitary populations: Females inhabit exclusively female home ranges and disperse as juveniles; males inhabit home ranges that overlap with many females	Social flexibility allows for intraspecific comparison between social and solitary states Reproductive competition in group-living individuals may lead to dispersal and solitary-living High population density may lead to group-living Fitness of each tactic dependent on environment Captive animals show bi-parental care	(Schoepf & Schradin, 2012; Schradin, 2005, 2006; Schradin et al., 2012; Schradin, König, & Pillay, 2010)