A MEAL FOR EIGHT (LEGS): How spiders catch their food

Our planet is home to around 35,000-50,000 species of spider (the estimates vary), the vast majority of which spin webs made out of silk generated inside the spider’s body. As any arachnid expert will tell you, spiders weave their silky masterpieces primarily as a means of obtaining food. With strands stronger than the equivalent thickness of steel, spider webs are covered with sticky substances that ensnare their prey, trapping flies and even birds and snakes, ready for the web’s resident to deliver its venomous coup de grâce.

When an insect flying about and minding its own business collides with a web, which is often designed to be invisible until it is too late, the impact creates vibrations that alert the spider. Spiders have extra sensitive hairs on their legs, which are attuned to pick up the slightest movement coming from the web’s fabric.

However, arachnologists have not yet figured out how exactly the spider interprets the movement signals when its equivalent of a pizza delivery happens. In 2016, a team of scientists from the American state of Oregon decided to try and solve this puzzle by creating a web of their own.

Using nylon from parachutes, the team built a web that replicated a traditional ‘spoke’ layout, popularly associated with spiders. The strands of yarn were arranged radially and were held taut by a specially constructed machine with an aluminium frame, alongside an attachment resembling a spider placed centrally, as can be seen with garden spiders and orb weavers.



The vibrations caused by insects were reproduced with the help of a subwoofer-type speaker, and the spiral of the web was emulated with elastic cords. Ross Hatton, a member of the research team at Oregon State University, told GrandesMedios.com, the source of this story, of how realistic they made the web experiment, explaining that they used two different types of nylon rope, just as spiders use two different types of silk.

The artificial spider in the middle was calibrated to pick up vibrations from the speaker, even the slightest ones. As Hatton explained: “We started with the hypothesis that if you moved one of the radial lines slightly, the arachnid perceived that one moved more than the others,

“We also speculated, that the spider would go towards the line that undergoes a variation in its movement”

In other words, Hatton and his team expected the spider in real life to gravitate towards the line of silk from which the most movement was travelling from. However the result of the experiment was quite different from the team’s original hypothesis.

Far from being a simple case of only a single strand of the web notifying that it caught dinner, the team discovered that the cobweb gave off a complex pattern of vibrations, with some sections of the web being more sensitive than others. According to Hatton, at different frequencies of sound from the speaker, different web strands and layouts did not vibrate at all. Different parts and strands of the web vibrated only at certain frequencies and remained unresponsive at others.

These different frequencies of vibration are believed to help the spider identify what type of prey had crashed into its web, and perhaps also help it distinguish between live prey and inedible objects such as leaf fragments and debris. The study, which redrew the way people thought about how arachnids predate, was presented at the American Physical Society conference recently.


Vijay Shah { विजय }, Twitter, Twitter Inc. https://twitter.com/VShah1984

Tecnología GM, Twitter, Twitter Inc. https://twitter.com/TecnologiaGM

“Cómo perciben las arañas a las víctimas que caen en su red” – GrandesMedios.com/Grandes Medios (6 April 2016) https://www.grandesmedios.com/asi-detectan-las-aranas-a-sus-victimas/


“Spider and web” – Dwight Sipler, Flickr (23 September 2009) https://www.flickr.com/photos/62528187@N00/3948508109/in/photolist-71V8U2-9ReV6c-aqKQGv-dpdK7M-5roAqX-5roEwn-5roBTv-DV9Eq-mYCVp-6Hu2Eb-5tj1DG-9oBvU-jG4wh-8JZa3e-a9A2a9-8WDwtQ-afhCqA-8yN4WL-5vSbKd-e2eBjU-aj8tGX-6QTWyn-4VgnTS-4Vc9mt-9aCUoX-4WYuxd-6bSLvd-51ycz-4rhGUq-31bfxS-316GzT-316xNt-316yCg-31b8K7-31b9dh-31b4TG-316z6p-316wva-31bbq9-31bdXs-31b3iw-31b64m-316EZD-31b7tU-316xwZ-31b8nG-31bdvo-31bcvw-316y1V-31baXE-316w2a




A window view of the BT Tower, in Fitzrovia, central London. I took this picture on the 28th of August, 2012, on the first day at my new office in Tottenham Court Road, after my company relocated there from our old site in Bressenden Place, Victoria which was scheduled for demolition.

The BT Tower, formerly known as the ‘Post Office Tower’, was first built in 1961, with construction completed in 1964. Standing in at 191 metres (627 ft), it was initially devised by the then General Post Office as a means of ferrying telecommunications traffic from London to the rest of the UK. It was the tallest structure in London up until the 1980s, and had its own rooftop restaurant which sadly closed in the same decade.

“BT Tower” – Wikipedia/Wikimedia Foundation, Inc. https://en.wikipedia.org/wiki/BT_Tower
Vijay Shah via Facebook.

NEWS STORY: How to organise one

In this next article in the Half-Eaten Mind practical journalism series, we move on from how to interview to what happens when you return to base to begin writing your story or feature. Like any sort of story, a news story needs to have a structure. You must have a beginning, a middle and an ending. Traditionally in journalism, students were taught that news stories followed a structure best summed up as an inverted (upside-down) pyramid. All of the most important facts and parts, such as the ‘who?’, ‘where?’ ‘when?‘, ‘how?’ and sometimes ‘why?’ which lend the most weight to the story would appear first with background information and other hierarchically lesser items appearing further down. This is not always set in stone, especially for feature writers, but in ‘hard news‘ and human interest stories, it is inexcusable.

The Chumby running a widget that is displaying...
The Chumby running a widget that is displaying a Google News story, with human hand for size comparison. (Photo credit: Wikipedia)

Today’s article will focus on how to organise your  story. It is based on lecture notes received by myself at my old university during a course module on newswriting and reporting skills.

1. Every news story needs a good intro, or beginning. Aim to write a concise,engaging intro that gives the major news points of your story. In other words, the most significant facts and hook of the story need to appear here.

2. Following on from the intro, write a second paragraph providing the other major points that cannot be fitted into the intro.

3. Use the third, or perhaps another paragraph early in the story, to give background and explanations for your readers to understand.

4. The order of news elements in the article should be presented in descending importance. It does not have to be in chronological order.

5. Use quotes early on but also drop them in throughout the story. It is better to sprinkle your direct quotes throughout the copy rather than stringing them together or bunching them up in one paragraph. Quotes are useful in that they let news subjects speak out to the reader; communicating directly with the audience.

6. Make use of transitions during the story to ensure good reading and subject flow. Simple words like ‘but’ and ‘however’ can work well.

7. Whatever you do, avoid the temptation to editorialise. A news story should be free from any deliberate bias or opinion from the journalist writing it. As my lecturer wrote “No comment from you, please!’.

8. Ending a news story can be a bit of a brain-wracker. However, please avoid simply rounding off with ‘The End’. The final paragraph simply reports more news. In some cases, a quote can make a good ending point. Some other news stories will end with news elements revolving around the continuation of the story. For example, in a news report on the arrest of a drug dealer, the last paragraph may mention that he or she has been remanded in custody for a hearing at a given date and place. There is no room or indeed context in a news story for “they all lived happily ever after”.

“HOW TO ORGANIZE A NEWS STORY” – Alan Geere, BAMS Newswriting and Reporting, University of Westminster – class handout/information sheet.
“File:Chumby in hand.jpg” – Edward Yanquen, Wikimedia Commons (30 November 2007) LINK
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