Spiders inspire biologists to create artificial webs to capture airborne DNA for biodiversity monitoring

Global crisis loss of biodiversity challenges our current ability to monitor changes in ecosystems.

Environmental DNA, or Ednahas become a popular method. It involves taking a sample from the environment and extracting DNA to document the species that are (or have recently been) present.

Similar to matching barcodes with the price of an item in a supermarket, eDNA data is matched with the corresponding identification record in the reference database.

But most eDNA sampling occurs in water, with liters of liquid passed through a filter that holds DNA fragments for analysis. This method works very well for fresh water and marine speciesbut to a lesser extent on land.

Enter airborne DNA, or airDNA, new method not yet optimized for widespread commercial use, but holds great promise for collecting terrestrial biodiversity signals.

Researchers have studied whether Natural spider webs can be used to collect DNAbut our research goes even further.

Inspired by Halloween decorations, we developed artificial spider webs to test how good they were at trapping airborne DNA just like real ones. Our data show that artificial webs perform similarly to real webs in detecting terrestrial species.

History of DNA capture

Electronic DNA has been used to monitor changes in biodiversity, discover new species, and evaluate the success of restoration or eradication projects. It is easy to use, cheap and non-invasive, and is currently being used by citizen scientists, community groups and mana whenua.

But species that live mainly on land – mammals, birds, bats, reptiles, insects – are less well identified by this method.

One of first studies demonstrate the potential of vacuum-assisted DNA analysis at a zoological park in Huntingdonshire (UK). He collected DNA from 17 land-dwelling species, including black and white lemurs. howler monkeyssloths and tigers, as well as their food and other mammals and birds.

This stimulated further research, including the use of cheaper passive methods for collecting airborne DNA, based on the deposition of air on inert biofilters. Recent study investigated whether natural webs could provide a new way to capture traces of vertebrate DNA from the environment.

This work caused excitement among researchers, who immediately saw the potential of the webs to provide aerosolized DNA along with DNA obtained from the spiders themselves and their recent prey.

We shared the general excitement of our colleagues, but could not help but wonder about the potential negative consequences of widespread use of this method on spiders. The spiders are already there end of bad pressbut they play an important role in the ecosystem as natural pest and disease control agents. They eat about 800 million tons of insects every year around the world.

The use of natural webs is also less reliable, since their size and shape, as well as the duration and location of their deployment, depend on the case.

How do artificial networks work?

Compared to aquatic eDNA methods, both types of webs in our study revealed clear signatures of terrestrial communities. But they were also good biofilters for trapping fungi, perhaps by trapping floating fungal spores.

The ecosystem picture obtained using both types of networks compared with aquatic eDNA also shows that these methods are likely to complement each other, capturing a more complete catalog of species in both terrestrial and aquatic ecosystems.

This is great news: artificial webs are easy and cheap to build, and provide better control over the location, frequency and duration of DNA collection – all at a lower cost to nature.

Where to from here? Further improvements are on the way. Unanswered questions include how many artificial webs we need to sufficiently capture biodiversity, whether these webs will perform better or worse in windy or wet weather, and whether materials other than Halloween decorations can create even better artificial webs.

As we continue to explore these questions, perhaps nature's weavers will provide us with further inspiration that will help us create even better biomechanical solutions for measuring biodiversity.

This article has been republished from Talk under Creative Commons license. Read original article.