About us | Contact us


News search
News archive


Book reviews

About us


Terms and Conditions of Sale


News detailview

October 7, 2016

Loner spiders prevail as pioneers

A spider looking to immigrate to a different environment is three to four times more likely to survive if it goes by itself, as opposed to as part of a group. "This is a pretty surprising result that breaks from long-held intuitions that moving as a group would enhance survival rates (for social organisms)," said Jessica Purcell, an assistant professor of entomology at the University of California, Riverside, who is a co-author of a just-published paper on the topic.

This is an Anelosimus studiosus spider. (Jonathan Pruitt, UC Santa Barbara)
One possible reason that individual spiders fare better than groups is that singleton immigrants entering an existing colony of natives are less likely to throw off the colony traits that determine colony survival. In this case, the trait that appears to be most important in determining colony survival is maintaining the right mixture of docile versus aggressive 'personality types' within the colony. The researchers plan to perform additional tests to distinguish between this and other possible causes of this pattern.

Local adaptation of animals has long been a central topic in ecology and evolution because adaptive, specialized traits can allow species to expand into new environments, which in turn can help promote diversification.

The research here focused on the species Anelosimus studiosus, which is found in temperate and tropical areas in North America and South America. It is one of about 30 species of spider, of more than 40,000, that is social, meaning it lives long-term with others of the same species.

The researchers collected spiders at four sites in Tennessee and Virginia and brought them back to the lab to determine their personality type - docile or aggressive. They used several methods to test spiders' personality types, including whether the spiders huddle together with fellow spiders or isolate themselves as aggressive loners, how quickly individual spiders attack prey, and how they react when perturbed.

After determining personality type and individually marking the spiders, they were returned to the field and monitored for three months under the three scenarios the researchers were studying.

These scenarios were: (1) individual spiders placed in a foreign environment; (2) individual spiders with their native colonies placed in a foreign environment; and (3) individual spiders placed into a pre-existing colony in the foreign environment.

While the researchers found variation in survival rates based on whether an individual or group was transplanted, they found individual personality did not impact survival rates on its own. Spiders that were moved across contrasting environments with their groups were almost certainly doomed to perish, along with their colony mates, in colony extinction events. Whereas, spiders that moved across environments alone, regardless of whether or not they joined pre-existing groups, had survival rates similar to those of native spiders. The researchers conclude that a mismatch between the colony traits of immigrant colonies and the colony traits favored at their new site is likely responsible for these findings. One of the implications of these findings is that selection against particular colony traits may prevent immigrants from moving across environments, which could ultimately create the right conditions for speciation.



<- Back to the news list
Print page

Latest publications:

E.K. Massey, F. Ambagtsheer, W. Weimar (Eds.): Ethical, Legal and Psychosocial Aspects of Transplantation – Global Challenges

W. Weimar: Ethical, Legal and Psychosocial Aspects of Transplantation

F. Ambagtsheer, W. (Eds.): Trafficking in Human Beings for the Purpose of Organ Removal

S. Schmidt, D. Knuth (Eds.): iSAR+ New Media in Crisis Situations

K. Conrad, W. Schößler, F. Hiepe, M.J. Fritzler: Autoantibodies in Systemic Autoimmune Diseases – A Diagnostic Reference. 3rd Edition

C. Boccato, D. Evans, R. Lucena, J. Vienken: Water and Dialysis Fluids – A Quality Management Guide

>> eBook: www.ciando.com

W. Weimar, M.A. Bos, J.J.V. Busschbach (Eds.): Ethical, Legal, and Psychosocial Aspects of Transplantation – Global Issues, Local Solutions
>> eBook: www.ciando.com

R. Bambauer, R. Latza, R. Schiel: Therapeutic Plasma Exchange and Selective Plasma Separation Methods, 4th Edition 2013
>> eBook: www.ciando.com

Infection, Tumors and Autoimmunity, by K. Conrad et al. (Eds.)
>> eBook available at www.ciando.com or www.doccheck.com

The EULOD Project Living Organ Donation in Europe – Results and Recommendations, by Ambagtsheer, F.; Weimar, W. (Eds.)

Public Engagement in Organ Donation and Transplantation (from the ELPAT Public Issues Working Group), by Randhawa, Gurch; Schicktanz, Silke (Eds.)

The General Practice Guide to Autoimmune Diseases, by Y. Shoenfeld, P.L. Meroni (Eds.)

How to Write and Evaluate Psychological Reports, by Westhoff, Karl; Kluck, Marie-Luise

Task-Analysis-Tools (TAToo) – Step-by-Step Support for Successful Job and Work Analysis, by Koch, Anna; Westhoff, Karl

Markets, methods and messages. Dynamics in European drug research, by Fountain, Jane; Asmussen Frank, Vibeke; Korf, Dirk J (Eds.)

Hypertension and Cardiovascular Aspects of Dialysis Treatment, by Branko Braam, Kailash Jindal, Evert J. Dorhout Mees


(C) 2004-2015 Pabst Science Publishers