I have been wondering about several aspects of my latest readings.
For example, I find it curious that in large social groups mixed between related and non-related individuals, young ground squirrels would play more with related individuals and not with unrelated individuals (Mateo, J.M., 2003).
The play rates followed a gradient of relatedness (e.g. siblings, three-quarter siblings, non-relatives) and were not reflective of a dichotomous choice between full siblings and non-kin.
Generally, species appear to try and distinguish between relatives and non-relatives sometimes exhibiting preferential treatment to relatives while excluding them from other interactions such as mating.
This, of course, corresponds with such fundamental processes as evolution and collective use (including defense) of resources (including guarding offspring and mates that are considered resources, as well).
Thus, it would appear that animals might form social groups where resources are plentiful and benefits might accrue from sharing those resources with other related individuals or at least with individuals that offer great benefits to the ‘common cause’ (e.g., in herds and sounders and nursing colonies where females raise their offspring together in large maternal groups but the mothers in those groups are not necessarily related to one another although they can be and frequently are due to natal philopatry).
These theories, however, predict that with a greater abundance of resources, species might want to try to form larger groups.
This is not the case, for example, with wolves (Kittle, A.M. et al., 2015) where habitat quality (resource abundance) is not determinant of pack size although it is of territory size.
That is to say, wolves do not appear to consequently attempt to enlarge their social groups if resources are more abundant although it can happen due to side effects of fluctuations in territory size etc. (e.g., if more pack members are needed to defend the territory).
This could possibly be explained with biological and social mechanisms because every species is also restricted by reproductive rates and by how the reproduction is managed on a social level (breeding exclusivity).
However, wolves can allow subordinate breeders in a pack in times of plenty which could compensate for a limited litter size and which could reduce the social breeding restrictions (although, in many cases, dispersal might be the only viable method of acquiring a breeder’s status if otherwise the risk of inbreeding was high).
Also, wolves have been known to adopt even unrelated or more distantly related (or ‘dispersed and returned’) individuals into their packs.
Therefore, the absence of group size response to resource abundance suggests, to me, that there is a certain preference, a threshold for the wolves regarding the size of their social group.
It could be explained by the deep and individualized bonds that wolves make (which might become diffused in larger social units) and it could be explained with such phenomena as free riding or decreased food uptake per capita which is not compensated for with increased kill rates because wolves do not need such big groups to take down prey (2 – 3 wolves are quite enough for most prey except bison although more wolves might be needed to defend the carcass against scavengers, e.g., ravens).
Essentially, it does not appear that wolves strive to form bigger groups upon every chance they come across.
Meanwhile, for example, badger social groups appear to follow resource abundance and badgers do not restrict their social grouping to kin exclusively (although the low dispersal distance by badgers additionally pose a necessity to avoid inbreeding).
In the UK, badger groups can reach rather extreme densities (more than 12 individuals per group) and the individuals are not always related and exchanges of members between neighbouring groups can occur.
Different species lead varied lifestyles and some are more solitary (e.g., lynx) than others (e.g., red deer).
However, many species appear not to mind interacting and, for example, to keep their weaned offspring in their home ranges for longer than absolutely necessary until the bond has to be disrupted upon a new breeding season; and interactions are observed even between individuals that belong to species that have previously been considered solitary. e.g., European river otters.
Interactions are also observed between otherwise agonistic individuals in secure, stable, overabundant feeding situations (garbage dumps, supplementary feeding sites etc.).
I, personally, feel that even though some species do not have such a great need for extensive or intensive and, more importantly, numerous and frequent interactions, all species are quite happy to interact at times (rather than they would prefer to never interact with anybody) if this does not pose a significant threat to them or to their resources (including offspring).
This has made me believe that there are minimum and maximum socializing thresholds to desired interactivity levels that are species-specific.
In this post, however, I am not going to draw very strict line between interactions within a species (with related or non-related conspecifics) and interactions between species (with other, phylogenetically related species as well as with competitors, predators, prey, scavengers etc.).
Usually, interactions between. e.g, predators and prey or competitors are not regarded as social interactions but I would like to include them to this type of exchange because I find that these types of interactions can compensate for more permanent, intraspecific social interactions and that it is the lack of compensation that encourages some species to form larger groups or to seek more frequent encounters with other conspecifics.
While predator-prey or competitor interactions do not provide what we typically consider bonding, they provide important opportunities to challenge one’s intellectual and physical capabilities and to engage with another living being that is not mechanistic in its response (the way, for example, abiotic resources can be).
My theory is that there is a certain need for interaction (in this case, perhaps I should avoid calling it social interaction although, personally, I still think of it as social because sociality does not necessarily have to be affiliative and it is rather defined by hierarchies and order and exchanges that allow to exercise one’s skill as well as one’s status) which is defined by the species social environment experience (e.g., in what types of social groups the animal grew up in) as well as by species cognitive evolution (e.g., the genetically inherited potential that should be developed through interactions with the world and its objects and subjects).
I believe that species which grow up with many siblings have an experiential propensity to engage in interactions that satisfy the requirements developed during early infancy.
But I also believe that species that are cognitively evolved have a genetic propensity to test their potential in interactive situations.
These two mechanisms can act in a combined manner.
Also, the need for complex interactions is not always satisfied by increasing the quantity of interactions if quality can be increased (e.g., in wolf groups where group members share many types of interactive experiences and where the relationship quality might compensate for relationship quantity).
Meanwhile, requirements for interactions gained in early infancy might not be met through further involvement with many conspecifics or through the forming of social groups but, additionally or alternatively, through interactions with other subjects in one’s environment such as their prey, their competitors, scavengers of their kills etc.
These interactions outside of one’s species, if frequent and engaging (challenging), might even limit the capacity of a species to interact further with other conspecifics rendering them more solitary than foragers of plant, fungal etc. (more predictable) resources.
Thus, for example, pine martens, stoats and other such mustelids might have spent their early days in relatively large sibling groups but the need to maintain the interaction level later in life could be compensated for by the resource acquisition strategy where the species has to interact with varied prey species that are mostly very mobile and ‘demanding’.
Meanwhile, badgers frequently forage on less responsive and ‘entertaining’ resources (earthworms, larvae, fruits, seeds etc.) and they might develop a need to interact more which is why, when possible, they form social groups.
Wolves interact with prey as well as with scavengers which might limit their requirements and they might not feel inclined to enlarge their social groups (that offer high quality interactions) whenever possibility arises.
Wolf interactions with their prey might, in some ways, more engaging and, in some ways, less engaging than ambush predator interactions with their prey species.
It is even possible that species develop hunting strategies that correspond to their social experience and inclinations, e.g., wolves that interact very closely and physically within their social group, also chase, herd, tackle etc. their prey while, for example, lynx that grow up with their mother and frequently only one sibling prefer to remain unseen until the last moment and to observe rather than to engage in a fully physical capacity for long bouts.
I might dedicate another post to reasons why I consider predator-prey interactions and competitor interactions to be social interactions, as well, but here I conclude with my theory of thresholds of interactions and meeting the requirements developed experientially or genetically not only through intraspecific pair/kin group formation and expansion but also through interactive exchanges with other species in a wider array of contexts.
Strange as it may appear, predator-prey interactions might even become prioritized in species with slightly less evolved cognition.
The ground squirrels in the study preferred to play with relatives over non-kin which might be counterintuitive because a greater diversity of playmates would surely promote the development of better, more varied skills and strategies.
However, it is possible and likely that, first and foremost, one should develop one’s fundamental abilities.
Namely, an individual in their early stages of development might prefer to play with a more related (more similar) individual in order to achieve control over the most basic competencies.
Before we learn to add new techniques to our skill set, we should explore our inherent potential and to develop what has already been given to us and what we are the best bestowed with.
Therefore, playing with family members and related individuals might assist in learning not really ‘about the world’ but ‘about oneself’.
While greater cognition level might allow to extend this learning to more external experiences.
Similarly, a species might prefer interacting with prey rather than with a larger group of conspecifics because they have a limited capacity of interactivity and their interactivity should be, at the same time, productive in a very practical manner and also aimed at developing their existing and inherent skill set (rather than seeking more novel interactions that would benefit species that have enhanced problem-solving needs and).
Notes by Ieva 