Follow
Researchers found – after amplifying and sequencing DNA samples in a lab – that cobwebs hold not only the DNA of the spider, but also the DNA of its prey.
Charles C.Y. Xu, a graduate student in the Erasmus Mundus Master Programme (MEME) in evolutionary biology – a programme that promotes and enhances quality in higher education specifically through scholarships, and which is renowned especially in Europe – said that for researchers in a number of fields (like pest management, or conservation ecology), knowing what spider builds the web and what type of prey it typically consumes is very important.
As genetic sequencing becomes less expensive, it allows researchers to collect their information from spiders without having to capture or even kill them, according to Xu. Therefore, the whole process of collecting DNA becomes a lot easier, he added.
In the study – published November 25 in the journal PLOS ONE – the researchers analysed the webs of three black widow spiders. For several days, Xu and his colleagues kept the spiders in three separate enclosures and fed them each two crickets. After they took the DNA samples, their goal was to find DNA from the prey – the house crickets (Acheta domesticus) – and from the spiders that built the web – the Southern black widow (Latrodectus mactans).
Because they needed a lot of DNA, the researchers used primers, which are strands of short nucleic acid sequences, to amplify the DNA and create millions of copies of it.
The team amplified the gene cytochrome oxidase 1, which is one of three mitochondrial DNA (mtDNA) that can be used to recognise or identify a species. This gene is normally used for a process called DNA barcoding. This process uses a short genetic marker in the DNA of an organism identify to which species it belongs to.
Although DNA barcoding has been used in the past to identify bats, jellyfish, or fungi, it has never been used to identify spiders, according to the researchers.
Apart from DNA barcoding, there is another more accurate technique that uses DNA to identify species, and it is known as next generation meta-barcoding sequencing. Xu said that this slightly modified and more advanced technique could provide detailed information as to what kind of spiders and insects live in a particular area.
Pest management may also benefit from these genetic technologies that are a lot more sensitive and accurate than any traditional sampling method, to find which species of spider has invaded someone’s home, or which species of spider hatches in boxes of goods.
Image Source: spiderbytes.mango.mikeboers
Germaine Hicks
Germaine is an avid sports fan and as such, he decided on his current career path with the idea in mind that he would never, ever miss a Yankee game. Until now, he managed to make good on that promise. As you’ve probably guessed, he’s our go-to sports guy.
