Need to track animals around the world? Scientists say you can tap into the 'Into the Spider-Verse'

The rich tapestry of life on Earth is fraying, largely due to human-induced habitat loss and climate change. As more species disappear, researchers are racing to track the global decline in biodiversity, understand its impacts and counter it through conservation efforts.

These efforts rely on accurate animal monitoring, which can be difficult, time-consuming, and expensive.Now, a new study published in the journal iscienceresearchers present evidence of spider webs, a new low-cost, non-invasive tool that can be used to monitor animals.

Here's how things worked for a while: If you want to know which animals are in a particular location, hike or climb into their habitat and wait to see or hear them. However, this approach can have drawbacks.

“When you're repeatedly entering hostile environments to conduct visual inspections,” says Josh Newton, Ph.D. “That's a bit difficult,” says a student majoring in genetic biodiversity at Curtin University in Perth, Australia.

Another issue with traditional monitoring is that it may involve capturing animals. “It's stressful for the animals,” Newton said. “Especially if you're looking for rare and endangered species, that's not great and it's not what you want to do.”

DNA is everywhere

In recent years, scientists have turned to other ways to monitor biodiversity. They use environmental DNA (eDNA). This is simply the DNA of different organisms present in the environment. You can think of this as the ecological version of “everywhere at once.”

“All species that exist are[s] In a given environment, in a given ecosystem, they may die, decay, urinate, defecate, breathe, etc.,” said Morten, an evolutionary biologist at Curtin University. Arendoft says. This series of processes then “facilitates the shedding of cells into the environment, and all cells contain DNA.”

Researchers have detected eDNA by swabbing it from leaves and flowers, filtering it from water, extracting it from the air, and even finding it in the intestines of dung beetles and the blood of leeches.

One day, as Allentoft was walking around Lake Bibra in his Perth home, he noticed a pile of giant webs built by spiders that weaved golden orbs in the trees.

“When I was studying biology, I was told that spider webs have spider webs. [are] It’s sticky,” he says with a laugh. “As you can see, they're messy and dirty. And I thought to myself, 'Maybe it's this spider web.' [are] Large passive air filter. They sit there for days, weeks, and even months. They are very likely capturing DNA. [is] It's floating.''

past works

Kangaroos, wallabies, oh!

So Newton drove to Karakamia Wildlife Reserve, a wooded area about 30 miles outside Perth, and collected cobwebs from branches and bushes. “If you look at it, shrek “When you see Princess Fiona collecting the fairy threads in the spider's web for Shrek, that process is very similar,” says Newton. “Just grab a stick and wrap it around it.”

Even if the webs were dismantled, the spiders were never harmed or recovered. “We just gently coaxed them off the web,” Newton says.

Of course, it's unclear what the spiders thought of this approach.

“That's why we say it's non-invasive,” Allentoft added with a laugh.

Back in the lab, Newton amplified a small amount of DNA from the web. They were filled with genetic material from animals Down Under.

“It was amazing,” Allentoft said. “We could see these kangaroos [and] Wallaby. Other animals found included nine mammals, 13 species of birds, a biker frog, and a snake-like lizard. The forest analysis also detected DNA from non-native Australian species such as the red fox, mouse, and black rat.

To ensure Webb was collecting DNA from local animals, Newton also collected samples at Perth Zoo. And those nests contained DNA from 21 birds, five reptiles, two amphibians, and 33 mammals, including giraffes, elephants, rhinos, orangutans, lemurs, and meerkats.

In other words, the technique worked. This represents a new way to track animal biodiversity and alert when to intervene to protect native species and step up efforts to eliminate invasive species.

“I think it's smart and cute,” says Elizabeth Clare, a molecular ecologist at York University in Toronto who was not involved in the study. “This is an excellent way to non-invasively sample terrestrial vertebrates. There are thousands of papers that have studied the movement of DNA in water, but very few on land. , more explorations like this are needed to narrow down how they accumulate and how long these signals last.”

For example, Newton doesn't know whether the nests he collected have been around for days, weeks, or months. However, some orb spiders build a new nest every night and destroy it in the morning. “Imagine he could collect DNA from spider webs,” Allentoft said. “Then they will have a very accurate picture of what species are actually present right now.”

Next, Newton and Allentoft plan to investigate how the placement and shelf life of different types of spider webs can tell them which animals are roaming nearby. This is their version of the World Wide Web, and it's packed with equally important information.

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