A Costa Rican pirate spider lives up to the family name: It tricks closely related orb weaver spiders into “walking the plank,” right to their doom.
Like any respectable pirate, pirate spiders have an extensive bag of tricks. Some species delicately strum the threads of other spiders’ webs to convince the arachnids they’ve caught an insect, only to strike when the web owner comes to collect its prey. Others mimic on a web the signature rhythms of a different spider’s courtship dance, luring would-be suitors to their deaths.
On a trip several years ago to a biological reserve in Costa Rica, researchers were the first to witness a hunt by a little-known species called G. siquirres. It cleverly exploits the way other spiders make their webs to get a meal, the team realized.
At nightfall in the steamy lowland rainforests of Costa Rica, orb weavers let loose “floating lines” — single strands of silk that blow in the breeze until the free end sticks on another surface, such as a tree branch. The orb weaver then scurries across to secure the second anchor point, and this first moored line serves as the foundation for the web.
2023-09-18 07:00:00
Article from www.sciencenews.org