An international team of scientists discovered that the pattern spiders depict, help them attract prey throughout the day.
The researchers from Australia, Singapore, Taiwan, and the UK have positioned various cardboard models of the golden orb-weaver onto actual webs in the field. They wanted to test various combinations of colors and patterns and found out that the yellow, as well as the black and yellow mosaic pattern, are crucial for attracting prey throughout the day.
Insects Are Naturally Attracted to Yellow
The webs of the golden orb weaver, scientifically known as Nephilia pilipes, also lures prey during the night, and the tests showcased that the yellow color alone was incredibly efficient at attracting nocturnal insects. These types of spiders are usually found in various light environments, and contrasts between numerous species have unveiled a connection between light conditions and orb-weaver body color patterns.
Species that create their webs in incredibly lit settings are more probably to develop the yellow mosaic color pattern, discovered to be incredibly efficient at luring prey in these studies. Even so, this color patter hardly develops in species that have almost no chances to attract prey, perhaps because they are hidden in an isolated place or constructed their webs in dark caves.
Dr. Po Peng, the lead author of the study, said, “Our discoveries indicate that the effectiveness of color-luring to attract prey might be a major driver for the yellow mosaic pattern being present in distantly related orb-weaver spiders.”
The importance of the yellow color may be due to the yellow pollen and flower heads being dynamic in flowers that indicate to diurnal pollinators. Earlier analyses have also discovered that some nocturnal Lepidoptera, a.k.a moths and butterflies, can discern colors in faint light settings and naturally prefer yellow.
The Color and Pattern Have Major Significance
Orb weaving spiders contain approximately 12,500 species and make about 28 percent of the 45,000 described spider species. The scientists conducted the field research at Huayan Mountain in Taiwan between 2008 and 2009. They developed five kinds of cardboard models that looked like Nephilia pilipes with their legs outspread.
One of the spiders imitated the spiders’ natural color patterns, and the second had blue spots instead of yellow to test the significance of color. The third combined the merged area of the yellow into one part to test the significance of the pattern. The fourth and fifth cardboard model types were completely yellow and black, respectively.
“To find paper with color properties most similar to the body parts of N. pilipes, Szu-Wei Chen (co-author) and I did several tours over dozens of stationery stores collecting samples and measuring their reflectance.” Said Po Peng.
In the field analysis, the scientists replaced a live spider with a random model in the spider’s web. They recorded the reactions to insects of the fake spiders, gathering a combined 1,178 hours of video footage during night and day.
“Previous studies suggest that the area of bright body parts is constrained by diurnally active, visually hunting predators,” said Po Peng, “But our results indicated that the yellow mosaic pattern on nocturnal spiders does not represent a trade-off between prey attraction and predator avoidance.”