Featured Research

from universities, journals, and other organizations

Spiders are partial to a side order of pollen with their flies

Date:
December 18, 2013
Source:
University of Exeter
Summary:
Spiders may not be the pure predators we generally believe, after a study found that some make up a quarter of their diet by eating pollen. Biologists have now demonstrated that orb web spiders -- like the common garden variety -- choose to eat pollen even when insects are available.

An orb weaver spider with a pollen-filled web.
Credit: Dirk Sanders

Spiders may not be the pure predators we generally believe, after a study found that some make up a quarter of their diet by eating pollen.

Dr Dirk Sanders of the University of Exeter demonstrated that orb web spiders -- like the common garden variety -- choose to eat pollen even when insects are available.

Spider webs snare insect prey, but can also trap aerial plankton like pollen and fungal spores.

Dr Sanders, alongside Mr Benjamin Eggs from the University of Bern, conducted feeding experiments and a stable isotope analysis on juvenile spiders to see whether they incorporate plant resources into their diet.

They discovered that 25 per cent of the spiders' food intake was made up of pollen, with the remaining 75 per cent consisting of flying insects.

The spiders that ate both pollen and flies gained optimal nourishment, with all essential nutrients delivered by the combination.

Dr Sanders, of the Centre for Ecology and Conservation at the University of Exeter's Penryn Campus, said: "Most people and researchers think of spiders as pure carnivores, but in this family of orb web spiders that is not the case. We have demonstrated that the spiders feed on pollen caught in their webs, even if they have additional food, and that it forms an important part of their nourishment.

"The proportion of pollen in the spiders' diet in the wild was high, so we need to classify them as omnivores rather than carnivores."

Orb web spiders regularly take down and eat their webs to recycle the silk proteins, and it had been suggested they may 'accidentally' consume the pollen during this process.

But the study found this to be impossible due to the size of the grains ingested, indicating that they were actively consumed by the spider coating them in a digestive enzyme before sucking up the nutrients.


Story Source:

The above story is based on materials provided by University of Exeter. Note: Materials may be edited for content and length.


Journal Reference:

  1. Benjamin Eggs, Dirk Sanders. Herbivory in Spiders: The Importance of Pollen for Orb-Weavers. PLoS ONE, 2013; 8 (11): e82637 DOI: 10.1371/journal.pone.0082637

Cite This Page:

University of Exeter. "Spiders are partial to a side order of pollen with their flies." ScienceDaily. ScienceDaily, 18 December 2013. <www.sciencedaily.com/releases/2013/12/131218100133.htm>.
University of Exeter. (2013, December 18). Spiders are partial to a side order of pollen with their flies. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2013/12/131218100133.htm
University of Exeter. "Spiders are partial to a side order of pollen with their flies." ScienceDaily. www.sciencedaily.com/releases/2013/12/131218100133.htm (accessed September 16, 2014).

Share This



More Plants & Animals News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

AFP (Sep. 16, 2014) Scientists say a female colossal squid weighing an estimated 350 kilograms (770 lbs) and thought to be only the second intact specimen ever found was carrying eggs when discovered in the Antarctic. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

AFP (Sep. 16, 2014) Since the arrival of Ebola in Ivory Coast, Ivorians have been abandoning their pets, particularly monkeys, in the fear that they may transmit the virus. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins