Environmental DNA (eDNA) is facilitating biodiversity monitoring and the detection of invasive species by studying the genetic material that living organisms leave in water, soil, air and other environments. Researchers have recently determined that spider webs are effective at capturing DNA shed by animals and plants in the surrounding environment. In a comparison conducted by Joshua Newton near Perth, spider webs were the most successful method for identifying vertebrates compared with other passive sampling tools.
However, approximately 40 natural webs had to be destroyed to collect meaningful data. Subsequently, in trials with artificial webs, Angela McGaughran from New Zealand’s University of Waikato detected the DNA of nearby cows, sheep and exotic birds; artificial webs also proved more successful than natural webs at capturing fungal spores.
Why it matters
This approach expands the options for collecting data in biodiversity research without capturing living organisms directly and could contribute to monitoring invasive species. The destruction of natural webs during sampling constitutes a limitation in terms of the method’s practicality and environmental impact. The ability of artificial webs to detect DNA from different animals in the surrounding area offers researchers an option that does not depend on natural spider webs; their success with fungal spores also shows that their use is not limited to vertebrates. However, how consistently the method will produce results in different environments and conditions remains a question that needs to be answered beyond the findings currently available.