Ant-Mimicking Spider Relies on a “Double-Deception” Strategy to Fool Different Audiences

From snakes that look like they have two heads to color-shifting chameleons, deception is at the heart of many animals’ survival strategies.  Both visual and chemical predator deterrence are well-documented phenomena in the animal world, but new research on ant-mimicking spiders, published in PLOS ONE, may be the first documented case of a species that uses visual deception to elude one group of predators, and chemical deception to escape another.

Ant mimicry, or myrmecomorphy, is a tactic used by numerous spider species, and with good reason, since many predators steer clear of preying on ants due to their aggressive tendencies and often unpleasant taste. Ant-mimicking spiders can have body shapes that closely resemble those of ants, as well as colored patches that look like ant eyes.  Combine these characteristics with behaviors such as waving their front legs in the air to resemble probing ant antennae, and these spiders can successfully convince predators to look elsewhere for their next meal.  The jumping spider Peckhamia picata is one such ant mimic whose visual signals are an effective deterrent for visually focused predators, such as other species of jumping spiders.  The picture below shows a jumping spider on the left and the ant it imitates on the right.

1 Ant mimic and predators

The PLOS ONE study shows that the ant-mimicking spider can also elude predators that rely heavily on chemical signals to identify their prey.  In the current study, the spiders successfully eluded spider-hunting mud-dauber wasps (pictured below), and received significantly less aggression from the ants they mimic than other non-mimicking jumping spiders. The researchers presented wasps with a choice between freshly killed ant-mimicking and non-mimicking spiders. In all of the trials conducted, the wasp probed both types of spiders with their antennae, but every time the wasps chose to sting and capture a spider (seven out of eight times), it chose the non-mimicking spider.The researchers also staged encounters between Camponotus ants and live ant-mimicking and non-mimicking spiders.  After probing them with their antennae, the ants were significantly less likely to bite the ant-mimicking spiders than non-mimicking ones.  These results demonstrate that the jumping spider has a remarkably effective ability to deceive potential predators who focus on chemical cues when selecting prey.

2 wasp

The researchers point out that the spider is not a chemical mimic of the ant species it emulates. Insects rely heavily on hydrocarbons secreted from their cuticles (the hard outer covering of invertebrates) to identify and signal one another. It turns out that ant-mimicking spiders have very low levels of these molecules, only a small fraction of the amount found in non-mimicking spiders and the ants themselves. While further research is required to fully explain the jumping spider’s chemical mechanism for predator evasion, a likely explanation is that the low level of these chemicals does not register as significant to a probing ant or wasp, and the chemical evasion is accomplished in this way.

This study may be the first to describe an animal using a “double-deception” strategy:  visual tricks and a deceptive chemical signature, both intended for different audiences.  The authors hypothesize that this kind of chemical deception is likely widespread among other visual mimics in the animal kingdom.

Related links:

Video of a ramblin’ ant-mimicking jumping spider (great music)

Spiders gather in groups to impersonate ants

Citation: Uma D, Durkee C, Herzner G, Weiss M (2013) Double Deception: Ant-Mimicking Spiders Elude Both Visually- and Chemically-Oriented Predators. PLoS ONE 8(11): e79660. doi:10.1371/journal.pone.0079660

Images:  Images come from Figure 1 of the manuscript

B11 Satellite Participant List

Below is a list of participants at the Berlin 11 Satellite Conference for Students and Early Stage Researchers. 

 

First Name Last Name Affiliation
Birgit Adam Max Planck Society General Administration
Carolyn Anderson University of California, Davis
Jack Andraka  
Penny Andrews University of Sheffield
Dorcas Aryeetey Kwame Nkrumah University of Science and Technology
John Paul Bagala Gulu University
Martin Ballaschk FMP Berlin, Leibniz-Institut für molekulare Pharmakologie
Ilija Bilic Max Delbruck Centre for Molecular Medicine
Carl-Christian Buhr European Commission
David Carroll Queen’s University Belfast
Sara Cerdas Faculty of Medicine University od Lisbon
Leslie Chan University of Toronto
Anjelika Deogirikar Hertie School of Governance / Georgetown
Benedikt Fecher HIIG
Patrick Flack Charles University Prague
Andre Franca LMU Munich
Matthias Fromm Free University Berlin / Freelancer
Dor Garbash CRI
Harriet Gliddon Imperial College London
Stian Haklev University of Toronto
Ahmed Hassan Mansoura University Faculty of Medicine
Marie Hauerslev University of Aarhus
Mats Haug SAIH
A’man Inayah Alfaisal University
Heather Joseph SPARC
Roshan Karn Tribhuwan University Teaching Hospital
Stefan Kasberger University of Graz
Iryna Kuchma EIFL
Eva Lien SAIH
Prateek Mahalwar Max Planck PhDnet
Gabriella Marino Pontifical Academy of Science
Joseph Mcarthur University College London
Jai Kumar Mediratta University of Nebraska-Lincoln
Daniel Mietchen Museum für Naturkunde
Ross Mounce Open Knowledge Foundation
Ayoub Msalilwa International Medical & Technological University
Daniel Mutonga University of Nairobi
Ilia Nadareishvili Davit Tvildiani Medical University
Uvania Naidoo University of Cape Town
Cameron Neylon PLOS
Meredith Niles NAGPS
Lucy Patterson Max Delbrück Center (MDC)
Mark Patterson eLife
Daniel Payne Robert Gordon University (Scotland)
Anna Pechenina University of North Texas
Tom Pollard Ubiquity Press
Dimitar Poposki University of Zagreb
Ulrich Pöschl Max Planck Institute
Slobodan Radicev Eurodoc
Thilo Rattay BVMD, IFMSA
Bernard Rentier University of Liège
Kostas Repanas Agency for Science, Technology and Research
Sofia Ribeiro EMSA
Jason Robertson Central Michigan University / University of Fribourg
Adam Roddy University of California, Berkeley
Katarzyna Rybicka Jagiellonian University
Shervin Safavi Max Planck Institute for Biological Cybernetics
William Schuerman MPI for Psycholinguistics
Christopher Schürmann BVMD, IFMSA
Nick Shockey R2RC
Jovan Shopovski Macedonian Union of Young Researchers
Raniere Silva University of Campinas
Elena Simukovic Humboldt-Universität zu Berlin
Ingrid Solheim University of Bergen
Kimberly Solovy University of Maryland, Baltimore
Alek Tarkowsi Creative Commons Poland
Angelica Tavella University of California Berkeley
Georgina Taylor University of Tasmania
Mike Taylor University of Bristol
Darcy Thompson Lund University
Daniel Tobon Universidad Tecnologica de Pereira
Tracey Vantyghem University of British Columbia
Ashley Wills Erasmus Medical Centre Rotterdam
Marcin Wojnarski University of Warsaw
Yan Zhu Stanford University

Live Webcast of B11 Satellite

LIVE WEBCAST | SCHEDULE | SPEAKERSDETAILS

We will live webcast the Berlin 11 Satellite Conference for Students and Early Stage Researchers at this URL, starting at 09:00 CET on November 18th. The webcast is free and open to all, and online participants will be able to participate remotely through Twitter using the conference hashtag #berlin11. Please share the link to the webcast with any individuals or organizations who may be interested in participating remotely.

The webcast will be embedded in this page just before the conference begins on Monday morning.

ERC Gets It Half Right: Do Deposit Immediately, But Not Institution-Externally

The European Research Council’s new Green Open Access Mandate has got it half right.

Yes, deposit should be immediate, whether or not access to the deposit is embargoed.

But, No, the deposit should not be institution-external but institutional. (External exports can than be done automatically by the institutional repository software.)

The reasons for this are strong, and many. Both the success of the ERC mandate, and its harmonization with other funder and institutional mandates are at stake.

See: BiorXiv: Deposit Institutionally, Export-Centrally

It’s not too late to fix this flaw in the ERC policy: I hope the drafters will have the motivation and sense to fix this.

Stevan Harnad

Academia Bound?

Commentary on “Open Access and Academic Freedom” in Inside Higher Ed 15 November 2013, by Cary Nelson, former national president of the American Association of University Professors


If, in the print-on-paper era, it was not a constraint on academic freedom that universities and research funders required, as a condition of funding or employment, that researchers conduct and publish research — rather than put it in a desk drawer — so it could be read, used, applied and built upon by all users whose institutions could afford to subscribe to the journal in which it was published (“publish or perish“), then it is not a constraint on academic freedom in the online era that universities and research funders require, as a condition of funding or employment, that researchers make their research accessible online to all its potential users rather than just those whose institutions could afford to subscribe to the journal in which it was published (“self-archive to flourish“).

However, two kinds of Open Access (OA) mandates are indeed constraints on academic freedom:

1. any mandate that constrains the researcher’s choice of which journal to publish in — other than to require that it be of the highest quality whose peer-review standards the research can meet

2. any mandate that requires the researcher to pay to publish (if the author does not wish to, or does not have the funds)

The immediate-deposit/optional-access (ID/OA) mandate requires authors to deposit their final refereed draft in their institutional repository immediately upon acceptance for publication, regardless of which journal they choose to publish in, and regardless of whether they choose to comply with an OA embargo (if any) on the part of the journal. (If so, the access to the deposit can be set as Closed Access rather than Open Access during the embargo, and the repository software has a facilitated copy-request Button, allowing would-be users to request a copy for research purposes with one click, and allowing the author the free choice to comply or not comply, likewise with one click.)

Since OA is beneficial to researchers — because it maximizes research downloads and citations, which universities and funders now count, along with publications, in evaluating and rewarding research output — why do researchers need mandates at all? Because they are afraid of publishers — afraid their publisher will not publish their research if they make it OA, or even afraid they will be prosecuted for copyright infringement.

So OA mandates are needed to embolden authors to provide OA, knowing they have the support of their institutions and funders. And the ID/OA mandate is immune to publisher embargoes. Over ten years of experience (of “performing a useful service by giving faculty a vehicle for voluntary self-archiving”) have by now shown definitively that most researchers will not self-archive unless it is mandatory. (The only exceptions are some fields of physics and computer science where researchers provide OA spontaneously, unmandated.) So what is needed is a no-option immediate-self-archiving mandate, but with leeway on when to make the deposit OA. This is indeed in a sense “optional Green OA,” but the crucial component is that the deposit itself is mandatory.

Funding is a red herring. Most universities have already invested in creating and maintaining institutional repositories, for multiple purposes, OA being only one of them, and the OA sectors are vastly under-utilized — except if mandated (at no extra cost).

The ID/OA mandate requires no change in copyright law, licensing or ownership of research output. Another red herring.

There are no relevant discipline differences for ID/OA either. Another red herring. And the need for and benefits of OA do not apply only to rare exceptions, but to all refereed research journal articles.

OA mandates apply only to refereed journal articles, not books. Another red herring (covering half of Cary Nelson’s article!).

As OA mandates are now growing globally, across all disciplines and institutions, it is nonsense to imagine that researchers will decide where to work on the basis of trying to escape an OA mandate — and with ID/OA there isn’t even anything for them to want to escape from.

The ID/OA mandate also moots the difference between journal articles and book chapters. And it applies to all disciplines, and publishers, whether commercial, learned-society, or university.

Refereed journal publishing will adapt, quite naturally to Green OA. For now, some publishers are trying to forestall having to adapt to the OA era, by embargoing OA. Let them try. ID/OA mandates are immune to publisher OA embargoes, but publishers are not immune to the rising demand for OA:

Paying for Gold OA today is paying for Fool’s Gold: Research funds are already scarce. Institutions cannot cancel must-have journal subscriptions. So Gold OA payment is double-payment, over and above subscriptions. And hybrid (subscription + Gold) publishers can even double-dip. If and when global Green OA makes journal subscriptions unsustainable, journals will downsize, jettisoning products and services (print edition, online edition, access-provision, archiving) rendered obsolete by the worldwide network of Green OA repositories) and they will convert to Fair Gold, paid for peer review alone, out of a fraction of the institutions windfall subscription cancellation savings.

It is not for the research community to continue depriving itself of OA while trying to 2nd-guess how publishers will adapt. That — and not OA mandates — would be a real constraint on academic freedom: The publishing tail must not be allowed to continue to wag the research dog.

Can #animalgarden Felix and AMI index Lucy’s repo? YES!

Can Felix and AMI index Lucy’s repo? YES!

 

 

At UKSG (which I’ll blog later) I talked about repositories and said that without indexing they were of little value. So #animalgarden were excited to get a tweet from

 

111513_0959_CanFelixand2.png

Lucy Ayre @lastic

 

#uksglive hard not to get excited by Peter talking about content mining. Turning PDFs into CSV/XML files. Index my IR Peter!

 

Lucy is from LSE. Professor Felix Q Potuit is also from LSE. He’s trying to index #animalgarden repository:

111513_0959_CanFelixand3.png

He’s asked AMI to do the electronic material:

 

So Felix and AMI would love to help Lucy. What does PMR think?

PMR thinks it’s a great idea! We could have a hack day or two. Let’s get in everyone who might be excited (not just from LSE, but everywhere – Birkbeck, OKFN, and London hackers and Brit Lib, and Cottage Labs, and booklovers and …). Buy them lunch and provide wifi.

And let them loose and see what they can do.

Yes – we have the prototypic technology to read the contents of repositories. We can turn PDFs and DOC into XHTML. We can extract facts , which can be used for research, or indexing.

#animalgarden look forward to hearing from Lucy!

 

 

Picked Clean: Neanderthals’ Use of Toothpicks to Fight Toothache

Toothpick1

The toothpick —an often unnoticed tool for post-meal rituals and appetizer stability—has played a greater role in our ancestors’ health and comfort than many would imagine. In a world before dentists, Neanderthals and modern humans took oral hygiene into their own hands using the only tools they had readily available: little bits of nature they found surrounding them.

Researchers from Spain have presented evidence in PLOS ONE that Neanderthals used small sticks or blades of grass not only to remove fragments of food from between their teeth, but also to lessen the pain caused by periodontal disease, a form of gum disease. While multiple human and Neanderthal remains have been found showing evidence of toothpick use, the authors propose that the combined evidence of toothpick use and gum disease suggests that Neanderthals were perhaps practicing an early form of dental care.

The samples in the image above show an adult’s upper jaw with three teeth left intact found at the Cova Foradà cave site in Valencia, Spain, amidst animal remains and tools dated to the Mousterian era (300,000-30,000 years ago). The adult teeth, believed to belong to an individual between 35-45 years old, show heavy wear on the top surface and exposed roots, the result of a lifetime’s consumption of fibrous and abrasive foods like meats and grains. There are no signs of cavities in the remaining teeth, though decayed bone and the porous surface texture of the left side of the jaw indicate the presence of gum disease.

Two distinct grooves are present on the sides of the existing premolar and molar above the crown of the tooth. These grooves were caused by consistent dragging of a tool across the side of the tooth. The existence of these marks above the gum line indicates heavy dental wear and disease. Here, the gums had receded and left the base of the tooth unprotected. With the roots exposed, it would be easy for leftover debris from meals to get stuck and put pressure on already inflamed gums. The use of a foreign object pushed between the teeth would remove any particles lodged in this sensitive area. Without the extra burden of invasive food detritus, force on the gums would be reduced and irritation and pain would decrease.

Over the last few years, studies have shown that Neanderthals were capable of complex behaviors and emotions, may have used a sophisticated language, were more often right-handed than left, and were generally not the inferior cousins some thought they were. As this study shows, they practiced dental care as well. So, the next time you’re heading out of your favorite restaurant, take a good look at that bowl of toothpicks at the front: the contents could very well be evidence of one of our oldest habits.

Check out more coverage of this article in National Geographic and Archaeology magazine.

Citation: Lozano M, Subirà ME, Aparicio J, Lorenzo C, Gómez-Merino G (2013) Toothpicking and Periodontal Disease in a Neanderthal Specimen from Cova Foradà Site (Valencia, Spain). PLOS ONE 8(10): e76852. doi:10.1371/journal.pone.0076852

Image Credit: Image from Figure 2 of the manuscript

Copperbelt University Library participates in the 2013 Open Access Week Celebrations

The Copperbelt University participated in the Open Access celebrations for the first time in 2013. The event came at a time when both lecturers and students at the Copperbelt University were either coming out from their early sessional examinations or were preparing for missed examinations. However, the Library had prepared for the celebrations and proceeded with the programme of activities as planned.

The Open Access week was successfully launched by the Copperbelt University Vice-Chancellor on 21 October 2013. The launch was then followed by a training of trainers “ToT” on OA and “Effective access to electronic resources.” Throughout the week, the Library distributed Open Access brochures to a wider Copperbelt University community. Fliers for faculty and Administrators were also distributed for advocacy and publicity purposes.

According to the initial programme, the Library planned to hold workshops for four days from 22 to 25 October 2013 targeting more than 200 participants. Apparently, the sessions were reduced to three days as 24 October was a gazetted Independence Day public holiday. Workshop sessions were held at the Main and the School of Medicine campuses.

The workshops were conducted successfully, though the optimal target number of workshop participants was not achieved during the OA Week. Apparently, there has been an overwhelming feedback for the need to hold similar workshops for both lecturers and students. The pronounced outcome from the events is that those who participated in the workshops have become Open Access advocacy champions and will continue publicizing the OA Movement activities in collaboration with the CBU Library staff