Austen Brown and Jenny Eng
Theridion nigroannulatum. Image taken from Reference 4
Spiders are notoriously solitary, typically only making contact with other members of their species as newly hatched young and when mating, an event still often characterized by aggression (10).Despite this common preception, a special subset of spiders exhibit the astounding behavior of social cooperation.
Spider societies take on various forms, from colonial to cooperative and have evolved many seperate times, resulting in diversity of much scientific interest. The study of sociality in spiders can be approached from Nikko Tinbergen's four different categorizations of behavior: phylogeny, ontogeny, mechanism and adaptation. The following pages will discuss spider sociality as it relates to each of these four categories as follows:
Phylogeny: the multiple evolutions of social spider species
Ontogeny: the acquisition of foraging and dispersal behaviors in social spiders and the generational patterns of colony development
Mechanism: how the behaviors of foraging and maternal care are orchestrated
Adapation: the advantages that group living confers on social spiders