Cornell researchers studying Australian social huntsman spiders have discovered that younger siblings thrive when raised in nests with older siblings. Bigger brothers and sisters capture bigger, juicier prey, which they - at least occasionally - share with their younger siblings.
Through field data and laboratory experiments, the researchers showed that younger siblings weighed substantially more when they shared the prey of their elder brethren. Since smaller spiders eat relatively little, there is little to no cost to the older siblings. And healthier family groups help carry on that family's genes.
A study by Eric Yip and Linda Rayor, published in the journal Animal Behavior, describes how prey sharing can directly benefit spiders living as a group.