Silk before capture webs
An animal can produce silk without building an orb web. This distinction matters when studying early spider relatives. In the Devonian Attercopus, researchers identified silk outlets along the edges of plates rather than on the movable spinnerets of true spiders. The fossil therefore preserves a combination of features that cannot simply be mapped onto a living spider.
Revisiting an interpretation
Attercopus was initially interpreted as a very early spider. Re-examination led to its placement in the extinct Uraraneida in 2008. New material and a closer look at anatomy can change an explanation. The oldest known fossil is also not necessarily the actual origin of a group: it is the oldest evidence recovered and recognised so far.
What we can infer
Early silk may have served for lining, wrapping or orientation. These are proposed functions, not directly observed Devonian behaviour. We separate the preserved structure from the inferred use and from questions that remain unresolved. Our journey follows evidence without pretending that fossils provide an unbroken chain of direct ancestors.
A dated clue
Attercopus material from Gilboa was described from deposits about 386 million years old. This dates preserved evidence, not necessarily the first origin of silk. True spiders are documented from the Late Carboniferous. The distinction raises questions about when particular lineages acquired particular characters.
Sources & image credits
- Selden, Shear & Sutton (2008) · Fossil evidence for the origin of spider spinnerets ↗
- Garwood et al. (2016) · Almost a spider: a 305-million-year-old fossil arachnid and spider origins ↗
Sources checked: 1 November 2026. Figures and records carry the qualifications stated in each article.