may not be as great of an advantage to engaging in chivalrous behavior. Social behavior Group living Spiderlings can choose to join a group web or build their own web, with the majority of individuals choosing to live in a group. They make this decision when they are 4–5 days old. Each strategy has its own costs and benefits, as group living decreases the amount of food allocated to each spider but also decreases the amount of silk each spider must produce, benefitting individuals by demanding less energy expenditure. Although spiders in groups tend to have smaller abdomens than those living alone, indicating lower foraging success, spiders live in groups more often than would be predicted by chance. This may be due to the high energetic cost of producing silk and increased amount of silk needed to build a web alone as opposed to within a group. An individual's decision to build its own web or join a group web is based on its level of recent feeding success. H. pluchei spiderlings co-inhabiting a web do not cooperate in other realms, such as prey capture or wrapping remainders of prey in silk, and instead engage in display and fighting behaviors as they compete for prey, with larger spiders tending to win these fights. These conflicts can sometimes escalate to death, especially when the spiders are of similar sizes. Spiders in the same web will occasionally cooperate on wrapping prey, but only when the prey is very large. This cooperation may only occur because the spiders cannot see each other and are therefore unaware of each other’s presence. Enemies Predators Holocnemus pluchei are preyed upon by jumping spiders of the family Salticidae, including Portia fimbriata and Portia labiata. In response to invasions from other species, H. pluchei will “bounce,” or move their legs rapidly up and down while remaining grounded on the web in an attempt to dislodge the intruder. Invading species employ aggressive mimicry tactics when invading the webs of H. pluchei and are often able to avoid setting off the resident’s “bouncing” strategy, enabling these web invaders to successfully capture their prey. Interactions with humans and livestock Holocnemus pluchei are considered household spiders and build webs in the eaves, basements, and attics of houses. Although they are venomous, they are not dangerous to humans, likely due to the inability of their fangs to produce a strong enough bite. There