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Direct evidence of successful or failed predation is rare in the fossil record but essential for reconstructing extinct food webs. Here, we report the first evidence of a failed predation attempt by a pterosaur on a soft-bodied coleoid cephalopod. A perfectly preserved, fully grown soft-tissue specimen of the octobrachian coleoid Plesioteuthis subovata is associated with a tooth of the pterosaur Rhamphorhynchus muensteri from the Late Jurassic Solnhofen Archipelago. examination under ultraviolet light reveals the pterosaur tooth is embedded in the now phosphatised cephalopod soft tissue, which makes a chance association highly improbable. According to its morphology, the tooth likely originates from the anterior to middle region of the upper or lower jaw of a large, osteologically mature individual. We propose the tooth became associated with the coleoid when the pterosaur attacked Plesioteuthis at or near the water surface. thus, Rhamphorhynchus apparently fed on aquatic animals by grabbing prey whilst flying directly above, or floating upon (less likely), the water surface. It remains unclear whether the Plesioteuthis died from the pterosaur attack or survived for some time with the broken tooth lodged in its mantle. Sinking into oxygen depleted waters explains the exceptional soft tissue preservation.Constraining the diets of extinct taxa is vital for understanding predator-prey relationships, reconstructing extinct food webs and for understanding the evolution of multi-trophic interactions 1-4 . Fossilised gut and throat contents, known as content fossils 4 , are perhaps the most renowned line of direct evidence for extinct predator-prey interactions. These fossils have greatly increased the known dietary ranges of many extinct clades, including carnivory in Mesozoic mammals 5 and piscivory in theropod dinosaurs 6 . However, well-preserved content fossils are extremely rare and there is an inbuilt bias towards preservation of 'harder' items (e.g. scales and shells) and towards items consumed immediately prior to death 4,7 .Other direct lines of evidence used to infer diets include coprolites 8 , regurgitalites 9 , tooth marks from supposed feeding events 10,11 , healed bite traces from failed predation attempts 12 (which sometimes contain embedded teeth) and the preservation of predators and prey together as a result of fatal encounters 13 . These types of evidence are slightly more abundant than content fossils and are also useful for gaining unique insights into the foraging and feeding behaviours and the habitat preferences of both predators and prey 1 . For example, the presence of bone regrowth in the damaged caudal neural spines in the hadrosaurid dinosaur Edmontosaurus has been interpreted as evidence of active predation by the large theropod dinosaur Tyrannosaurus rex and that T. rex, consequently, was not an obligate scavenger 12 . Inferring the taxonomic identities of predators and prey from these types of evidence, however, can be difficult 1,14 .Well-preserved evidence of predator-prey relationshi...

Summary A terminology of the dispersion of birds, and of the ways in which it comes about, is proposed and explained. An examination of recoveries of ringed female Pied Flycatchers Ficedula hypoleuca show that many first breed a considerable distance from their birthplace, in contrast to the situation in the Blue Tit Parus caeruleus and Nuthatch Sitta europaea. The degree of such dispersion in these species, and presumably therefore the gene flow, is inversely correlated with the number of geographical races they contain. Results of experiments designed to investigate the types of dispersion mechanism occurring in F. hypoleuca indicate that both “dispersal” and “spacing” occur in birds of all ages, and that they are usually not oriented, but that the spacing of older birds which have not been constantly faithful to place usually leads to a previously known place.