Navigation Links
Spiders who eat together, stay together: UBC research

The ability to work together and capture larger prey has allowed social spiders to stretch the laws of nature and reach enormous colony sizes, UBC zoologists have found.

The findings, published in this week's edition of the Proceedings of the National Academy of Science, may also explain why social spiders thrive in tropical areas but dwindle with increasing latitude and elevation.

"The size of organisms tends to be constrained by a scaling principle scientists call 'surface to volume ratio,'" says Leticia Avils, lead author and associate professor in the UBC Dept. of Zoology. While organisms typically have energetic needs proportional to their volume, they must acquire nutrients through their surface.

"As the organism grows, this surface to volume ratio declines. In a way, this is how nature keeps the sizes of various species in check."

The same principle may apply to social groups. The surface area of the three-dimensional webs social spiders use to capture prey does not grow as fast as the number of spiders contained in the nests; so number of incoming prey per spider declines with colony size. But Anelosimus eximius, a species of social spider notable for its enormous colony size some total more than 20,000 individuals have gained the ability to stretch that law by cooperating and thus capturing increasingly large insects as their colonies grow.

"The average size of the prey captured by the colony increased 20-fold as colony size increased from less than 100 to 10,000 spiders," says Avils, who studied the spiders in the wild in Amazonian Ecuador with undergraduate student Eric Yip and graduate student Kimberly Powers.

"So even though the number of prey falls sharply as the colony grows, the biomass that individual spiders acquire actually increases."

The study also found that large prey, while making up only eight per cent of the colony's diet, contributed to more than 75 per cent of its nutritional needs.

"But that only works to a certain point," says Avils, who adds that the biomass of prey consumed by the colony peaks when the colony reaches between 500 and 1,000 individuals.

As for the scarcity of social Anelosimus species in higher elevations and latitudes, "there simply aren't enough large insects in those areas to sustain this type of foraging behaviour," says Avils.


Contact: Brian Lin
University of British Columbia

Related biology news :

1. Life Sciences Discovery Fund awards health research project grants
2. UGA researchers win $9.2 million stem cell grant from NIH
3. Research exposes new target for malaria drugs
4. Broad Institute researchers introduce next generation tool for visualizing genomic data
5. Spanish researchers discover significant leatherback turtle nesting beaches in the Caribbean
6. DOE and USDA announce more than $10 million in bioenergy plant feedstock research
7. EPA funds ground-breaking Lyme disease research
8. ORNL researchers analyze material with colossal ionic conductivity
9. UNH researchers tag first-ever free-swimming leatherback turtles in New England
10. Small research at MSU leads to advances in energy, electronics
11. FSU, Magnet Lab researchers license critical petroleum data
Post Your Comments:
(Date:6/2/2016)... YORK , June 2, 2016   The Weather ... is announcing Watson Ads, an industry-first capability in which consumers ... by being able to ask questions via voice or text ... Marketers have long sought ... the consumer, that can be personal, relevant and valuable; and ...
(Date:5/24/2016)... , May 24, 2016 Ampronix facilitates superior patient care by providing ...  3D medical LCD display is the latest premium product recently added to the range ... ... ... Sony 3d Imaging- LCD Medical Display- Ampronix News ...
(Date:5/12/2016)... 12, 2016 , a brand ... overview results from the Q1 wave of its quarterly ... was consumers, receptivity to a program where they would ... health insurance company. "We were surprised to ... Michael LaColla , CEO of Troubadour Research, "primarily ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... , ... Parallel 6 , the leading software as a service (SaaS) ... Virtual Patient Encounter CONSULT module which enables both audio and video telemedicine communication between ... Using the CONSULT module, patients and physicians can schedule a face to face virtual ...
(Date:6/24/2016)...  Regular discussions on a range of subjects including policies, ... entities said Poloz. Speaking at a lecture to ... he pointed to the country,s inflation target, which is set ... "In certain areas there needs ... economic goals, why not sit down and address strategy together?" ...
(Date:6/23/2016)... ... June 23, 2016 , ... UAS ... the launch of their brand, UP4™ Probiotics, into Target stores nationwide. The company, ... proud to add Target to its list of well-respected retailers. This list includes ...
(Date:6/23/2016)... (PRWEB) , ... June 23, 2016 , ... ... Plate® YM (Yeast and Mold) microbial test has received AOAC Research Institute approval ... of microbial tests introduced last year,” stated Bob Salter, Vice President of Regulatory ...
Breaking Biology Technology: