A New Independently Derived Social Spider with Explosive Colony Proliferation and a Female Size Dimorphism 1

@article{Avils2006ANI,
  title={A New Independently Derived Social Spider with Explosive Colony Proliferation and a Female Size Dimorphism 1},
  author={Leticia Avil{\'e}s and Wayne P. Maddison and Ingi Agnarsson},
  journal={Biotropica},
  year={2006},
  volume={38}
}
Permanent cooperative sociality is rare in spiders. Here we describe sociality in a cobweb (Theridiidae) genus with no other known social species. In five areas of eastern Ecuador, we found nests of Theridion nigroannulatum containing from a single to several thousand adults living together in a communal web. Spiders cooperated in prey capture and shared their food. Subadult to young adult sex ratios were highly female biased, suggesting a strongly subdivided population structure as in other… 

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