General Mammalian Patterns [?--in no particular order] with an emphasis on Group-living taxa, especially, Social Biology & Behavioral Ecology--also see Twitter @cbjones1943... Conceptual Framework...
FIRST PRINCIPLES OF BEHAVIORAL ECOLOGY:: E[nergy]: Acquisition->Consumption->Allocation====> Worker &/or Reproductive &/or Dependent...(Males, T[ime] Minimizers; Females, E[nergy] Maximizers)
Mammals: Anisogamy-->Sexually-Antagonistic Selection-->Sexual Conflict-->Differential
T-E investment, including, Life History (males, time-minimizers;
females, energy-maximizers)-->Sexual Dimorphism, inc, Body
Size...constrained by dispersion of limiting resources [especially,
food for females, mates for males]--that may or may not not favor
group-living...[apply, for example, to evolution of male Alternative Reproductive Behaviors (ARBs) & female "counterstrategies"]...
For analysis, and where data permit, we will separate comments for large [>100 kg] & small mammals--as suggested in literature, e.g.,
https://pdfs.semanticscholar.org/3281/ad106c0d6a9fdc831b7725dc5d3460222136.pdf
Terminology & Context: Terminology in the field of Social Biology, here, related to Social Evolution, is not standardized ... for example, WD Hamilton & Stu A. West, define "social" in different ways, the former limiting use of "social" to Cooperation & Altrusim, the two [of four] categories of behavior [Selfish, Cooperation, Altruism, Spite] in which Recipient gains "fitness" benefits ... West, on the other hand, defines "social" as any interindividual interaction where either or both interactants benefit reproductively ... recall that "interdependence" is a necessary precursor to Cooperation, while Cooperation is a necessary precursor to the evolution of Complex Sociality ... here, I am thinking of Cooperation as per Hamilton--an interindividual interaction in which both interactants benefit in "fitness" ... related to the Major Transitions Approach, Complex Sociality [division-of-labor (cooperation between specialists); task, role, &/or morphological specialization] is, particularly, problematic, it seems to me ... if we view specialization along a continuum, say, from feeding specialization to DoL to reproductive DoL with "totipotent" workers or "helpers" to reproductive DoL with more or less "sterile castes" [social insect workers], do we accept the typical usage whereby Advanced Eusocial taxa are the most "complex" societies [the "pinnacle" of sociality as per Wilson (1971)]? ... though many Social Scientists would claim that interindividual interactions in humans represent the "pinnacle" of Complex Sociality, expert consensus among Social Biologists (e.g., B Crespi 2014) have concluded that humans cannot be classified, Eusocial, because this species does not display "reproductive division-of-labor" ... it is worth pointing out that the wide variety of human reproductive groups have not been systematically described, classified, or diagnosed, including, analysis of populations in which more than one architecture is found, such as all modern nation-states [e.g., monogamy, polygamy, promiscuity, etc.] ... whether & how & why these various conformations interact over Time & Space remains to be determined ... it is assumed that 1st Principles [T, E, acquisition, consumption, allocation] relative to abiotic [e.g., climate] & biotic [e.g., food dispersion; breeding sites] environmental regimes, as well as, constraints of limiting resources, as well as, species-typical female traits, always apply ...
1... most Mammals are "sexually segregated" [sometimes termed, "solitary" in the literature]; however, aggregations [temporary clumping of animals] may occur around clumped, limiting resources, especially, food [as, white-tailed deer may do in Spring when food is abundant & clumped]; other aggregations may form when animals migrate from one feeding &/or breeding ground to another; the term "herds" often refers to an aggregation ... the term, "group," is reserved for a reproductive unit ... Hamilton's Rule [rb - c>0 ----> rb > c] is widely accepted as a general formulation of Social Evolution ... according to Hamilton (1964), "social" behavior is limited to Cooperation & Altruism--the only conformations of interindividual interactions [Selfish, Cooperation, Altruism, Spite] whereby Recipient gains in "fitness" ... this definition of "social" should be derivable from Hamilton's equations ...
2... Several authors have claimed that large mammals have, cet. par., generalized phenotypes (e.g., Eisenberg 1981), presumably, related to evolution in heterogeneous regimes ["environmental grain" theory proposed by Richard Levins 1968. Wilson '75 posits that [1] phenotypic flexibility/plasticity is a general feature of social evolution of large mammals [n.b., the evolution of "learning" should be discussed here, including, the evolution of "social" learning requisite to Culture]; however, generalized phenotypes may represent [2] "canalization." Whether [1] or [2] is an effect of temporal variability & "grain" will depend upon patterns of variability [e.g., rainfall, hurricanes] relative to Generation Time [Is the environment trackable?] . For all of the topics in #2, you might want to take a look at my 2012 Springer Brief. Furthermore, to the extent that mammals exhibit generalized phenotypes, this trait would be expected to inhibit evolution of specialized morphologies, such as, morphologically distinct castes. See sections on generalized phenotypes in Eisenberg (1981).
7... Selander & Kaufman (1973) and others [see paper linked in #1 above] argue that large mammals have higher tolerance for genetic monomorphism.
8... The basis for Social Evolution in mammals is "milk", according to EO Wilson [1975, Sociobiology, Belknap: HUP] n.b. a number of authors claim that the basis for Social Evolution in mammals is the primitively [non-cooperative, non-altruistic] communal female group leading to polygyny [c.f. Wittenberger 1980]. The basis of Wilson's point, however, is that Mammal females are obligate caretakers of young, predisposing them to certain life-history trajectories, including, probably, receiving help, all limited by energetics. Recall the litany that females are "energy-maximizers," males, "time-minimizers." Some female mammals, extend maternal care [&, often, lifespan], a trait that will retard the evolution of "complex" sociality [specialization, eusociality] because extended maternal care prevents the evolution of reduced maternal care and the evolution of the de-coupling of Survival and Fecundity. Importantly, in humans, social insects, & "primitively" eusocial mole-rats [& "cooperatively-breeding" mammals?], an apparently rare life-history strategy is found [among females] whereby extended lifespan [a "slow" life-history trait] is combined with a high reproductive rate [a "fast" life-history trait]. In humans, however, extended lifespan is, apparently, combined with increased investment in maternal care; while, in social insects, social mole-rats, & "cooperatively-breeding" mammals [?], extended lifespan in associated with reduced maternal care--a necessary, though, not sufficient, condition for the evolution of higher "grades" of sociality [specialization, eusociality, genotypic altruism]. Further, reduced maternal care is a necessary trait associated with decoupling of Survival & Fecundity.
9... According to Wilson (1975, p 379), the four "pinnacles" of social evolution are: the colonial invertebrates [e.g., corals, bryozoans], the social insects, the non-human mammals, & humans]. n.b. reflective of a "major transitions" approach to the Tree of Life
10... Traits of the non-human mammals: aggressiveness & discord carried further in vertebrate, including, mammal, societies than in social insects...selfishness rules inter-individual interactions...no sterile castes [though reproduction may be suppressed chemically or by "choice"]...acts of altruism infrequent and usually directed toward kin, especially, offspring...cooperation usually rudimentary; though inequity & hierarchy virtually ubiquitous [wherever there is division of labor there will be inequity]...by human standards, some acts "brutal" [e.g., treatment of infirm & dying]...mostly after Wilson '75, p 380
11... Human social traits: humans remain "essentially vertebrate" in their social structure, but more "complex," not by reduction of selfishness but by evolution of intelligence and language [relate to phenotypic plasticity; learning, including, social learning (cultural mechanism); social parasitism; persuasion; manipulation; exploitation, etc]...elaboration of kin relations [cost-benefit]...human societies "approach" levels of cooperation in insect societies & far exceed social insect societies in communication...mostly after Wilson '75, p 380
12... Most "interesting" mammal orders: rodents, artiodactyls, primates, marsupials--"control group" for Class after Wilson '75 & Eisenberg '81 [social biology of largest mammal orders--bats, rodents--virtually unknown as of 1975]...mostly after Wilson '75, p 468 x
13... Traits labile [e.g., mode of intrasexual cooperation, degree of cohesion, openness of societies (c.f. "open" vs. "closed" groups)]. Many forms of interaction change seasonally, & patterns differ at species level. [after Wilson '75]
14... Phylogenetically, more primitive living marsupials and insectivores tend to be solitary. Species that forage nocturnally or underground are, also, mainly solitary. Eisenberg [1981] & Wilson [1975] posit that marsupials are the only "control group" we have for Class Mammalia as a whole.
15... As a rule, the most complex social systems within each Order occur in the physically largest numbers...true of marsupials, rodents, ungulates, carnivores, and primates [Why? maybe because diurnal and because of large brains (intelligence?)? Wilson '75 Also, refer to J.H. Crook's work with weaver birds and other work in Behavioral Ecology: need to evaluate dispersion (distribution and abundance in time and space) of limiting resources relative to behavior & social biology].
16... Species adapted to life in open environments more likely to be social. Rodents known to form coteries of mixed sexes are all inhabitants of grasslands. Ungulates--great herds predominantly found in grasslands and on savannas, though herds mostly loosely structured--but see, horses, mountain sheep, elephants, and a few others [zebras?] Wilson '75
17... The structure of mammal [vertebrate?] groups is thought to result from the tendency of females to select rich patches of food and that of males to select large aggregations of females. Because patch richness and the consequent number [and quality] of females [female group size] is expected to vary, the relative reproductive success [RRS] of females may, also, vary over time and space. See the following paper, for example:
http://eprints.uberibz.org/1173/1/jones_2008.pdf
Also, see:
Jones, CB (March, 1996) Relative reproductive success [RRS] in the mantled howler monkey: implications for conservation.
Neotropical Primates 4(1), pp 21-23.
18... Chapters on Mammals in Rubenstein & Abbott (2017), may not be very useful for treatments of general patterns of Social Biology in Mammals; however, see stimulating final, summary chapter in this ambitious edited volume.
19. IMO, the chapters in Wilson (1975) on non-human primates and on humans are not very useful for identifying patterns across the Primates, in
Homo sapiens, across Mammals [or, across vertebrates].
20... Tim Clutton-Brock's text,
Mammal Societies, not very useful for identifying general patterns of Social Biology in Mammals. This book is not a Synthesis for the Mammals in the way that Wilson's [1971],
Insect Societies, is a Synthesis for the Social Insects--even though TC-B titles his book,
Mammal Societies. This book is a highly selective literature review. See, however, the useful table of contents & #generateideas. re: sub-eusocial insects--their traits & trends--see James Costa's book,
The other insect societies which includes many ideas for research.
21... Neotropical social mammals require thorough treatment, review, and integration into the broader literature on mammals which is dominated by research in the Paleotropics. In South America, see, especially, caviomorph rodents [infraorder, Caviomorpha], uniting all So. American hystricognaths. n.b. all or most of these spp. are small-bodied, & they are related to Old World [hystricognath] social mole rats.
22... General Patterns...Gene Evolution...Convergence...Gene E. Robinson Lab [see Jenny Tung's preliminary, though, cutting-edge, work on mammals @jtung5]:
https://www.pnas.org/content/108/18/7472
23... Temporal division of labor [age (-graded) polyethism: Wilson 1971] is ubiquitous in social insects; how common is it in Mammals & other vertebrates? See [especially, tables]: Jones CB (June, 1996) Temporal division of labor in a primate: age-dependent foraging behavior.
Neotropical Primates 4(2): 50-53.
also, Wilson EO (1971)
The Insect Societies. Belknap [HUP], Cambridge, MA.
24. The following book by Bernie Crespi discusses correlates of sociality [p 66, pp 73-74]...note, especially, significance of "high value" of limiting resources [abode, mates, food, etc.]...again, shows need to study limiting resource dispersion [distribution & abundance in time & space]...
Crespi BJ, Morris DC, Mound LA (2004) Evolution of ecological and behavioural diversity: Australian Acacia thrips as model organisms. Australian Biological Resources Study, Canberra.
https://www.environment.gov.au/science/abrs/publications/thrips
25... How much of the variation in mammal behavior & social biology is explained by body size?
26. Nursing [mammary glands] predisposes mammal females to caretaking, dependency, subordinate [e.g., "helper"] status, & favoritism of kin &/or other females. But how are these adaptations affected by evolution in suboptimal ["poor"] conditions or conditions of intense competition [for limiting resources], or, say, drought or collapse of prey population?
27. See Part 4 of Eisenberg [1981] for discussion [also, tables] of mammalian behavior, including mating systems & social biology--see, especially, Chapters 31-33.. Eisenberg [1981] classifies mammal "mating systems" into 10 categories, reduced to 3 basic types: polygyny [1 male, >1 females]; polyandry [multiple-male : multiple female], in which females mate with >1 male [not necessarily "promiscuous", i.e., females may demonstrate selectivity or preferences; also, there may be "favoritism" in which an adult female & an adult male are likely to mate exclusively or commonly with each other]; monogamy [uncommon]
See Eisenberg's outdated but still interesting and classic paper, Eisenberg JF (1966) The social organizations of mammals, Handbuch der Zoologie, Band 8. Lieferung 39: 10(7): 1-92.
28... Feldhamer GA, Drickamer LC, Vessey SH, Merritt JF, Krajewski C (2007) Mammalogy. Johns Hopkins UP, MD: "typical mammalian pattern of preferring unrelated distant kin as mates;" Emlen's "ecological constraints" model + Trivers' reciprocity [+ "pay to stay"?] explain "helping" in mammals?--especially, patterns in social mole rats [do naked mole rats have castes since there is a specialized "disperser form" in this species?]...see Jarman [1974] for classification of mammalian social organization x feeding selectivity: least selective most gregarious, large, polygamous, & sexually dimorphic--Jarmon PJ [1974] The social organization of antelope in relation to their ecology. Behaviour 48: 215-267...need to integrate Jarmon's findings with those of Crook [1964, Behaviour Monograph X] on weaver birds, i.e. relationship between food dispersion [distribution & abundance] and social structure/organization...
29... Ricklefs RE, Miller GL [2000] Ecology, 4th Edition. W.H. Freeman & Co., NY: Part 4, Population Ecology, Section 4.2, The dispersion of individuals reflects habitat heterogeneity and social interactions--"The dispersion of individuals within a population describes their spacing with respect to one another."--clumped [aggregation (maybe poor choice of word)]--clumped [limiting] resources may be most common determinant of these patterns, also, tendency of offspring to remain in natal group --see #13 above; spaced [even spacing= hyperdispersion]; random ["In the absence of social antagonism, which results in a spaced dispersion pattern or mutual attraction, which leads to clumping, individuals may distribute themselves at random" Can use Poisson methods to evaluate dispersion patterns...also, see Index of Dispersion [Clark & Evans, 1954]...also, can evaluate "nearest-neighbor distance"--"interindividual distance" [IID] in primatology literature...again, see Crook, 1964, Behavior Monograph X...
30... When discussing patterns of grouping or "social" organization [in populations], I have the strong impression that Mammalogists tend to attribute the patterns to phylogeny, philopatry [patterns of dispersal x sex], and/or predation...a Crookian [Behavioral Ecology] framework seems not to influenced Mammalogy very much where a "Crookian framework" would entail the mapping of animals in a population on to the dispersion of limiting resources [distribution and abundance of limiting resources in time and space--ceteris paribus & on average relative to differential engergetics x sex--males, at least, adult males, expected to be "time-minimizers," females, at least, adult females, "energy-maximizers"]...
31... The (2007) edited volume on Rodents by Wolff & Sherman [link] should be read in association with John F. Eisenberg's 1981 book on mammalian "radiations" [op. cit.]...Eisenberg provides broad context for many topics [e.g., parental behavior, scent marking, infanticide]...
https://www.amazon.com/s?k=wolff+rodents&i=stripbooks&ref=nb_sb_noss
32... General patterns in Social Mammals [Social Vertebrates? Social Animals?]: EO Wilson [
Insect Societies, Belknap (Harvard), 1971] discussed "age polyethism" ["temporal division-of-labor": TDL; "primitive" (totipotent) eusociality] in social insects as a feature of eusociality, particularly, "primitive" eusociality [taxa displaying "totipotency," the capacity to switch from a reproductive to a non-reproductive state & vice versa, as opposed to "advanced" eusociality, taxa characterized by sterile castes]...this article* provides the first empirical evidence of temporal division-of-labor in a mammal [1996], the mantled howler monkey,
Alouatta palliata Gray, studied by the present author in Canas, Guanacaste, Costa Rica. Temporal division-of-labor ["age polyethism,"
"primitive" (totipotent) eusociality] may occur widely among social mammals, social vertebrates, and, possibly, all social animals, where Cooperation and/or Altruism [including, reciprocity] have evolved in group-structured populations...
i would speculate that TDL ["age polyethism;" "primitive" (totipotent) eusociality] is more energetically efficient than more opportunistic, and, perhaps, more flexible or plastic, modes of [social] behavioral expression & might be expected to evolve/occur in contexts favoring conservation of energy [e.g., in heterogeneous regimes]...since females are expected to be "energy maximizers" [metabolically, reproductively], TDL may be more likely to be observed in females compared to males ["time-minimizers"]...TDL is expected to be developmentally programmed [within some (statistically normal) species-typical, population-typical, range (x sex)], & conscious & aware processes may not be required for its generation...in ////?, Jones reported age-dependent expressions of conflict-resolution among adult males of the same
Alouatta species in the same location & group; these results require intense investigation, lab & field experiments, & modeling, including, for humans...it is important to investigate those conditions under which different energy-conservation strategies evolve x sex...since males are expected to be more robust under energy constraints, it seems likely that thresholds will be identified differentially x sex for the same endogenous and exogenous, including, social, stimuli/factors/conditions.
EO Wilson's 2019 book,
Genesis, advances the idea that many [social] Mammals, including, humans [ see**], may be "eusocial."
Where "temporal division-of-labor" ["age polyethism"] is demonstrated, taxa can be classified, "primitively eusocial" and/or Totipotent Eusocial [TE] this classification would apply, also, to any other Social Vertebrates or, indeed, to any other Social Animals, where "age polyethism" [TDL; "primitive" eusocial; TE] is identified. If "tradeoffs" [e.g., energetic, reproductive, survival] are most likely to be observed in "poor" conditions [e.g., heterogeneous regimes where "fitness" is compromised; recurrent drought, unpredictable food or water supply], "age polyethism" may evolve to minimize energetic costs in time and space. While females are expected to be most sensitive to energetic effects, males, also, may benefit, under some conditions, from age-dependent responses. Furthermore, there may be energetic [reproductive, survival] benefits in coordinating many maturational [age-dependent] and developmental [age-dependent] milestones or markers with one another as genetic and physiological energy-savings tactics and strategies.
33... Wolff & Sherman (2007, link) includes some interesting & useful chapters, though, terminology is not standardized [& is often confusing (e.g., "single-breeding," "multiple-breeding"--particularly, as they are discussed in relation to philopatry...see, for example, Chapter 21 by Lacey & Sherman, who needed to make Emlen's work on Ecological Constraints fundamental to their discussion of "philopatry")], and "species" is often employed where "population" is, rather, the correct term. Each chapter in this book has a Summary at the end that can be read before digging into the whole chapter. Some chapters in Sections, "Introduction," "Social Behavior," & "Comparative Sociality" are of particular interest to students of Behavioral Ecology & Social Biology. There are many allusions to the importance of environmental [exogenous] factors, including, dispersion of resources; however, there is no explicit integration of [John Hurrel] Crookian socioecology [Behavior Monograph X] nor is there integration of Emlen's Ecological Constraints model which is fundamental when combined with Crookian socioecology. For context & references (especially, Emlen, Crespi), see blogpost, this blog, of EO Wilson's,
Genesis.
Wolff & Sherman [2007], amazon.com:
https://www.amazon.com/Rodent-Societies-Ecological-Evolutionary-Perspective/dp/0226905365/ref=sr_1_1?keywords=jerry+wolff+rodents&qid=1580071530&s=books&sr=1-1
EO Wilson
Genesis review [blogpost, this blog]:***
http://vertebratesocialbehavior.blogspot.com/2019/04/review-of-eo-wilsons-new-book-genesis.html
34... Fundamental questions in Behavioral Ecology pertain to Population Structure relative to dispersion [distribution & abundance] of limiting resources in T(ime) & S(pace), also to Population Structure relative to Basic Laws of Ecology--Acquisition, Consumption, Allocation. Ultimately, we should be able to reduce "fundamental questions" to Thermal Biology [all Biology reduces to Heat], & all material phenomena reduceable to Physics----->expressible in mathematical terms.
31. T
owards general principles [GUTs] via studies of Biological Assembly...for group-living---->sociality, see literature in Physics on "queuing"...
... https://reintegratingbiology.org/wp-content/uploads/2019/12/Universal-Forces-That-Result-in-Emergent-Properties-Across-Different-Levels-of-Biological-Organization-Dustin-Rubenstein.pdf
...as "assembly" patterns & rules are investigated and identified, it is important to address the Physics literature on "queuing" [see my 2014 Springer Brief on mammalian social evolution, Chapter 4]...
...as "assembly" patterns & rules are investigated and identified, it is important not to ignore Thermal Biology pertaining to Social Biology...
35... Needs lots of research: Resource Partitioning in Group-living vertebrates--search for patterns search for rules [within & between trophic levels, including, differential focus on "frugivores," "carnivores," "omnivores," etc.]
36.
Mammalian Patterns [here, Rodents]: Chapter 3 in #Rodent Societies [Jerry Wolff & Paul Sherman, Eds, U of Chicago Press, 2007] concludes that most rodents are polygynous or promiscuous [the author prefers the latter]...the litany for #Mammals is that most mammals are polygynous...
37... Mammalian Patterns, Ch. 4 on female reproductive strategies in Wolff & Sherman, op. cit. does not identify general patterns but exposes several problems inherent to the literature on mammalian sexual selection in this book & in many other treatments [e.g.,
Mammal Societies by TCB, op. cit.]...for example: 1...the reason treatments of male reproductive strategies dominate the literature is that females are a LIMITING resource for males; males are not a limiting resource for females [------>selection]; 2...many treatments, such as this chapter, do not integrate optimality language and logic into their analyses; 3...many/most treatments are not derived from Crookian model of Behavioral Ecology/Social Biology [dispersion [distribution & abundance] of limiting resources [food, mates, sleeping sites, etc.] in Time & Space; 4...many treatments do not integrate Hamilton's Rule & logic into their analyses; 5...many treatments, especially, in Primatology/Anthropology, do not consider the various hypotheses advanced in an attempt to explain Multiple-Mating by Females [in many reports, only Hrdy's idea is advanced and/or the hypothesis that females mate multiply in order to diversify the genetic composition of litters]; 6...Trivers' 1972 chapter in Campbell's volume seems not to have been digested in many treatments of female reproductive strategies [e.g., mammal females, after parturition and after some threshold investment in "current" offspring, are understood to begin investment in future offspring (e.g., repair, mate choice, fertilization, gestation, etc.)]; this generalization may need to be and has been modified for older/old females; 7...females are, cet. par., "energy-maximizers"; males, "time-minimizers"...
38... this is a classic chapter by Jerry Wolff on alternative reproductive strategies in non-primate mammals...
https://www.cambridge.org/core/books/alternative-reproductive-tactics/alternative-reproductive-tactics-in-nonprimate-male-mammals/88AB2B7352642314032233C426A4A231
39.... following Chapter 7, by John L. Koprowski, in Wolff & Sherman...: "Conflict, both intersexual and intrasexual, has been remarkably influential in the evolution of mating systems of tree squirrels. Conflict among males appears to have been particularly important in promoting evasive behavior in females, led to reduced copulatory duration, promoted alternative reproductive tactics, and influenced postcopulatory tactics for minimizing multiple paternity. Conflict among the sexes likely acts to diminish reproductive success of any dominant individual male, as females mate with multiple males and often avoid active pursuit males. The reproductive skew among males, however, is substantial, and active pursuit males clearly are most successful. Intersexual conflict appears to increase the number of males that are able to mate due directly to the evasive behavior of females, a behavior that maintains the satellite tactic among males. The benefits to females of manipulating the types of competition remain unclear. Future research must quantify the costs and benefits of male and female tactics under different environmental and social conditions...." [95]
40... Gene E. Robinson and other researchers have pointed out that, in social insects, "coordination and control" is decentralized, while, in [most?] human societies, "coordination and control" is centralized...is C & C in [most?] Mammal societies [i.e., in most group-living Mammals], centralized? ... my initial impression based upon my knowledge of all mammalian Orders is that centralized group structure is not common ... dominance hierarchies, for example, would be characterized as a type of "Interdependence," a necessary precursor to social behavior [Cooperation] ... thus, perhaps, the evolution of centralized group architecture is evolutionarily "derived" ...
41... In Wolff & Sherman [op. cit.], Chapter Eight by Dobson & Oli, [using PCA] body mass & phylogeny explain most of the variation in life-history traits [age at maturity; age at last reproduction; juvenile & adult survival; fecundity]...these traits predict a species' position on the "fast-slow [life-history] continuum...should this dataset, also, be analyzed by body size separately--"small" Mammals vs "large" Mammals [unless i am mistaken, a "small" Mammal is considered one < 100 lbs]...
42... in the final analysis, is the most important reason to study Primates the fact that such a large proportion of species is group-living ["social"]--structured around philopatric females, often kin?
43... In Wolff & Sherman [op. cit.], Chapter 13 by Scott Nunes, "dispersal and philopatry" is discussed: "The dispersal process can be categorized as either natal or post-breeding.... In mammals, natal dispersal is more common than breeding dispersal, occurring in nearly all species. Natal dispersal has a strong sex-bias in mammals, with males typically emigrating in new home areas at higher rates or over greater distances than females." [150] "A variety of hypotheses have [sic] been proposes to explain the prevalence of female philopatry in rodents and other mammals.... The evolution of complex social systems among rodents and mammals in general has been suggested to be predicated upon philopatry and cooperation among kin living near each other [especially, philopatric females, often kin]." [162]
44... though authors may mention environmental or ecological factors, in general, few, if any, of the chapters in Wolff & Sherman integrate a Crookian model into their analyses [dispersion (distribution and abundance) of limiting resources in Time & Space]--but see Section, Comparative Socioecology, Chapters 29-37...these
excellent and important chapters address Families, Genera, & Species that could reasonably become model systems for the investigation of general mammalian patterns, Behavioral Ecology, & Social Biology [
Rattus &
Mus are already model systems in research Biology and Medicine]...taxa covered are: ground squirrels; marmots; semifossorial desert rodents;
Rattus &
Mus; Capybaras and Maras; Octodontid & Ctenomyid rodents; rock-dwelling rodents; African mole-rats; black-tailed gunnison's & Utah prairie dogs...
See Emlen's "ecological constraints" model:
http://max2.ese.u-psud.fr/epc/conservation/PDFs/HIPE/Emlen1982.pdf
See Greenwood's classic 1980 paper on dispersal in birds & mammals:
https://psycnet.apa.org/record/1981-29692-001
45... Wolff & Sherman Chapter 14: Gene dynamics and social behavior [F. Stephen Dobson] uses "F" statistics [Population Genetics] to investigate population structure, finding that, in many mammals, population structure is a function of dispersion of female kin groups...
n.b. "social breeding groups may slow the loss of genetic diversity from populations," a process adding to the list of benefits to group-living and, possibly, sociality [cooperation, altruism]...indeed, cooperation & altruism may evolve to insure or enhance these benefits [but what are the tradeoffs, the costs?]...though Anthropologists generally maintain that human sociality evolves from an ancestral state of monogamy, the evidence from Mammals summarized in this blogpost strongly suggests that the ancestral state is the female group, especially, the female kin group, responding to clumped, limiting resources [in heterogeneous regimes?]--as most treatments by mammalogists hold...polygyny [and/or promiscuity?] appear to be the most common mammalian sociosexual system, &, perhaps, as suggested by many researchers, males, in part, monopolize female groups to defend females & their limiting resources [saving energy for female "energy-maximizers"]...as an aside, what role dies Sexual Selection play in all of this...
46... is eusociality much more common than we generally think? Bernie Crespi, WD Hamilton, Nancy Moran quoted in this
NY Times article linked below...note importance of protected, reliable food source[s] and of protective, reliable housing [& protection from predators--see Bernie Crespi article linked below]...how about humans?; i have suggested that humans are "facultatively eusocial" in my brief communication, "Are humans cooperative breeders" in
Archives of Sexual Behavior discussed on this blog and linked below...
https://www.nytimes.com/1993/02/16/science/social-castes-found-to-be-not-so-rare-in-nature.html
"Are humans cooperative breeders: a call for research" (2011), CB Jones:
https://link.springer.com/article/10.1007/s10508-011-9741-5?shared-article-renderer
...thre conditions for the evolution of eusociality, Bernie Crespi [Are these general?]:
https://www.semanticscholar.org/paper/Three-conditions-for-the-evolution-of-eusociality%3A-Crespi/feb94b7e861ac0e14b8d575f39e33c0a28338419
47... when we speak of "generality" we are often speaking of Convergence--whatever our level[s] of analysis from gene/allele to whole organism...here is link to a now classic paper from Gene E. Robinson's lab; note generalizeability, convergent evolution, & "toolkit" concept...see Table 3.1 in my 2014 Springer brief--phylogenetic & convergent social features of "prehistoric" mammals...
https://www.pnas.org/content/108/18/7472
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http://vertebratesocialbehavior.blogspot.com/2020/01/age-polyethism-temporal-division-of.html
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https://link.springer.com/article/10.1007/s10508-011-9741-5?shared-article-renderer
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http://vertebratesocialbehavior.blogspot.com/2019/04/review-of-eo-wilsons-new-book-genesis.html