DNA barcoding identifies cryptic animal tool materials

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 118; no. 29; pp. 1 - 3
• Main Authors: Steele, Matthew P., Neaves, Linda E., Klump, Barbara C., St Clair, James J. H., Fernandes, Joana R. S. M., Hequet, Vanessa, Shaw, Phil, Hollingsworth, Peter M., Rutz, Christian
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 20.07.2021
• Series: Brief Report
• Subjects: Animals; Biodiversity; Biodiversity and Ecology; Biological Sciences; Botanics; BRIEF REPORTS; Cameras; Crows; Deoxyribonucleic acid; DNA; DNA Barcoding, Taxonomic; DNA, Plant - genetics; Ecology, environment; Ecosystems; Environmental Sciences; Fieldwork; Gene sequencing; Life Sciences; Materials selection; Nesting Behavior - physiology; Phylogeny; Plant species; Plant Structures - anatomy & histology; Plant Structures - classification; Plant Structures - genetics; Population studies; Raw materials; Systematics, Phylogenetics and taxonomy; Tool Use Behavior - physiology; Vegetal Biology; nest building; New Caledonian crow; animal construction behavior; DNA barcoding; tool use; Nest building; New Caledonian; Tool use; Crow; Animal construction behavior
• DOI: 10.1073/pnas.2020699118
• ISSN: 0027-8424; 1091-6490

Some animals fashion tools or constructions out of plant materials to aid foraging, reproduction, self-maintenance, or protection. Their choice of raw materials can affect the structure and properties of the resulting artifacts, with considerable fitness consequences. Documenting animals’ material preferences is challenging, however, as manufacture behavior is often difficult to observe directly, and materials may be processed so heavily that they lack identifying features. Here, we use DNA barcoding to identify, from just a few recovered tool specimens, the plant species New Caledonian crows (Corvus moneduloides) use for crafting elaborate hooked stick tools in one of our long-term study populations. The method succeeded where extensive fieldwork using an array of conventional approaches—including targeted observations, camera traps, radio-tracking, bird-mounted video cameras, and behavioral experiments with wild and temporarily captive subjects—had failed. We believe that DNA barcoding will prove useful for investigating many other tool and construction behaviors, helping to unlock significant research potential across a wide range of study systems.