Wednesday, October 31, 2007

Why do so many species live in tropical forests and coral reefs?

Via EurekAlert:

The latest development in a major debate over a controversial hypothesis of biodiversity and species abundance is the subject of a paper to be published in the 1 November 2007 issue of the journal Nature. The authors report good agreement between the species richness of two of the world's most vulnerable ecosystems -- tropical forests and coral reefs -- and a simple mathematical model building on the so-called "neutral theory of biodiversity." "We're helping to refine and improve this theory because it might have important implications for the effort to protect terrestrial biodiversity from climate change and urban development," says Jayanth Banavar of the Department of Physics at Penn State, a member of the research team.

The Nature paper is based on a counterintuitive assumption of neutral theory: that one can largely ignore interactions between species in modeling patterns of species abundance. The authors are physicists Igor Volkov and Jayanth Banavar of Penn State University, plant biologist Stephen Hubbell of UCLA (formerly of the University of Georgia), and physicist Amos Maritan of the University of Padua in Italy.

Among ecological theorists, neutral theory has sparked a six-year quarrel over the fundamental assumptions of their discipline. The Nature paper counters another scientific team's claim in 2006 that coral-reef diversity "refutes" the neutral theory. At the same time, the paper by Volkov et al., to be published on 1 November 2007, modifies the classical version of neutral theory that appeared in a 2001 book by Hubbell. (Graham Bell of McGill University also developed a neutral theory independently of Hubbell.) Banavar, Maritan, Volkov, and their collaborators have been active in the development of a mathematical framework for understanding ecosystems that builds on and clarifies Hubbell's neutral theory.

"Despite its controversial nature, neutral theory has proved to be a good starting point for understanding ecosystems," Maritan says. In a 2005 paper published in Nature, Banavar, Maritan, Volkov, and their collaborators demonstrated that tree-species abundance and diversity in the tropical forests can be explained by the density-dependence mechanism, in which birth, death, and migration processes are postulated to depend on the abundance of a species. In a Nature paper in 2006, they presented a theory for the time scales of neutral evolution that is in good accord with empirical data.

Another coral reef off the coast of Ishigaki-jima Island.
Click here for more information.

"Mathematical modeling is increasingly vital in the biological sciences, and the key challenge is to uncover the simplicity underlying the seemingly bewildering complexity," Banavar says. In recent years, theorists have struggled to reconcile neutral theory with more mainstream ecological models, such as the famous niche theory, according to which species survive by exploiting ecological "niches" to which they are uniquely and better adapted than other species. For example, a rare plant species might survive in a dense rainforest habitat by exploiting a peculiar soil composition for which it is genetically adapted. Niche theory seemed so commonsensical that many ecological theorists reacted fiercely when Hubbell published his hypothesis, because it implied that individual members of plant or animal species comprising a fixed total population could be modeled as if they were equivalent entities in a random evolutionary lottery influenced only by rates of birth, death, and immigration.

In Hubbell's 2001 book, The Unified Neutral Theory of Biodiversity and Biogeography, he pointed to a surprising feature of some measurements of relative species abundance distributions (RSAs). The measurements are indistinguishable from fictional distribution curves generated by models based on random processes; that is, processes in which the fates of hypothetical species owe purely to chance events in birth, death, and immigration rather than to their adaptive prowess. Of course, in real life, adaptation to niches is an obvious feature of living creatures. For example, polar bears are adapted to the chilly niche of the Arctic, not to the sultry niche of the tropics. Still, Hubbell's findings hinted that the abundance of species and the development of ecological communities and ecosystems owe more to chance processes, and less to biology, than previously had been assumed.

Since 2001, numerous researchers have published the results of field tests of Hubbell's theory, based on their analyses of life forms and habitats such as tropical forests, North American birds, tropical reef fishes and corals, marine benthic communities in intertidal zones, and pollen records of eastern North American during the Holocene. Test results have varied from strongly positive to strongly negative. Some groups have disagreed in their interpretations of the same data.

A coral reef near a diving point in Palau.
Click here for more information.

In March 2006, Maria Dornelas of James Cook University in Queensland, Australia, and her colleagues published in Nature their study of coral-reef communities in the Indian and Pacific oceans. They found the coral-reef species in various local communities differ from each other far more than expected by neutral theory, and they exhibit RSA patterns that are quite distinct from those of tropical forests. The Nature article was titled "Coral Reef Diversity Refutes the Neutral Theory of Biodiversity." In their new Nature article, Volkov et al. reply to this latest challenge by arguing that the Dornelas team's thesis is invalid because the spatial structure and degree of isolation of coral-reef communities is different from those of tropical forests. In their latest paper, Banavar, Maritan, Volkov, and their collaborators have reanalyzed the Dornelas dataset and have concluded that it and measurements of rainforest species are compatible with an extended version of neutral theory in which all species are equivalent and do not interact with each other or the environment. Their work shows that "a theory in which all interspecific interactions are turned off leads to analytical results that are in good agreement with RSA data from tropical forests and coral reefs," the Nature article says. This agreement is so despite the obvious differences between the two types of communities -- coral reefs being composed of "many small, isolated communities" and tropical rainforests being "larger and more connected."

Volkov et al. conclude that "one can make significant theoretical progress in ecology by assuming that the effective interactions are weak in the stationary states in species-rich communities such as tropical forests and coral reefs." Maritan says that ecosystems may have evolved to a stationary state in which the coexisting species are substantially noninteracting because that is the most probable outcome. The next step, Volkov says, is "the development of a framework for bridging neutral and niche theories through the realistic accounting of the most important interactions among species and with the environment; for example, ways in which tree species might compete for the same resources or harbor insect pests that affect their competitiveness with rival tree species."

"The six-year saga of neutral theory is an intriguing example of how a scientific hypothesis can fertilize stimulating new research while evolving over time in response to scientific critiques," Banavar says.


The research was supported by the John D. and Catherine T. MacArthur Foundation, the Mellon Foundation, Earthwatch, Frank Levinson and the Celera Foundation, NASA, the National Science Foundation, and MIUR/Italy.

Jayanth Banavar at Penn State: 814/863-1089,
Amos Maritan at the University of Padua: (+) 39 049 827 7175,
Barbara K. Kennedy at Penn State (PIO): (+1)814-863-4682,

Links to some nice high-resolution images of coral-reef scenes are on the Web at .

Tuesday, October 30, 2007

Ants : Artwork by Kari Ryder Wilkie

So, if anyone is in Cambridge sometime in the next month, take a walk on over to CCTV, where, if you look through the window, you will see an art show by yours truly entitled, of course, ANTS:

Video thumbnail. Click to play
Click To Play

From the CCTV website:
Kari was one of the local myrmecologists interviewed for Project Documentary 2007's film "Ants" Now she is back at CCTV, presenting her ant-themed artwork in a show at the Drive by Gallery from October 25th - December 5th 2007. You can learn more about Kari's artwork in this short video, as well as at her website .

QotD: Darwin on why hypotheses matter

Via Getting Things Done in Academia:

I sat in on a grad seminar the other day that presented lots of data, and whose “Goals” slide started with the words “To find out if….”. Much of the resulting input from the audience was of the sort: “Could your data suggest that..?”.

Reminds me of a story. A critic said that Darwin, in writing Origin, should have just “put his facts before us and let them rest”.

Darwin replied

“About thirty years ago there was much talk that geologists ought only to observe and not theorize, and I well remember someone saying that at this rate a man might as well go into a gravel-pit and count the pebbles and describe the colours. How odd it is that anyone should not see that all observation must be for or against some view if it is to be of any service!”

The best science is communicated as a narrative, a voyage of discovery, that presents your data in the light of different cool hypotheses.

That’s three parts to communicating science.

Data and hypothesis without a narrative ignores the fact that humans learn from stories.

Data and narrative without hypotheses is like watching a slide show from a stranger’s cross-country trip (”Where is this going fercryin’ out loud!?”).

Hypotheses and narrative without data is like an evening listening to free verse.

h/t Michael Shermer, Scientific American, October 2007

ANeT '07 - India

via AntVisions:

The conference was as it should be, lots of ant fanatics! Hosted by the Punjabi University, over 60 delegates from 15 countries attended this meeting. The highlight was without any doubt, Dr Rudolph J Kohout being honoured for his Lifetime contribution in the field of Myrmecology. A breathtaking cultural program organised by the Postgraduate students gave us all a feel for 'the real Punjab'. Session talks were spread out from nearly 9.00 in the morning to around 7.00 in the evening. Speakers were given 8 minutes, though most often this was quite flexible owing to some generous chair persons! We were off on a field trip to collect and watch ants at the base of Himalayas. The highlight for most was seeing Odontoponera transversa, while for others it was Oecophylla smaragdina. The journal of Asian Myrmecology was released and the articles in the first issue suggests a promising future for the Journal! All in all, a well organised conference by Dr Himender Bharati, attended by a nice community of 'ant people'. A must attend from now on!

Pictures by Archana and Thresi

Sunday, October 28, 2007

Pheidole working group

Jack Longino has posted an impressive first version of the Pheidole Working Group online:

From Jack:

The useful things on it are:
1) a complete taxonomic catalogue as an excel file. Barry was generous with his current Word doc with up to data catalogue. The fields are not all filled in, but the most important ones are.
2) my first ever Lucid key. At this point it just has HL, HW, SL, CI, SI in it, and some geography, but I think it is a pretty useful sorting tool, even at this crude stage.

any corrections, contributions, etc. welcome.

Sadly the lucid key isn't working right now, but hopefully will be up and running soon. Go check it out.

U. S. Neivamyrmex paper

From Gordon Snelling: a new revision of Neivamyrmex of America: It can be found at

Thursday, October 25, 2007

Planet Bob and Cybertaxonomy

Via: Antbase

This week the International Institute for Species Exploration (IISE), a new research institute based at Arizona State University, released Planet Bob. This short, humorous film is the first effort within the IISE's commitment in educating and bringing the science of Taxonomy closer to the public. It does a good job in shaking off Taxonomy's reputation as a dead science and in describing the field's central role in biodiversity studies.

Wednesday, October 24, 2007

Mark Moffett -- my new favorite person

So I was browsing around on the web today and came across a video of Mark Moffett on The Colbert Report. Which led to a video of Mark Moffett on Late Night with Conan O'Brien. Both are hilarious and if you haven't seen them already, you definitely should. I kind of wish I was Mark Moffett now -- scientist, adventurer, photographer, journalist. That sounds like a sweet gig. And I love his website. Go check it out if you haven't already.

Tuesday, October 23, 2007

Bostonia article on Traniello Lab

Bostonia, the Boston University alumni magazine, has a big article in its Fall issue about our lab. My advisor is, of course, mentioned prominently. So is my labmate Mario, who is working on ant brains, and they even quoted an ex-member of the lab. And Amy, my other labmate, has a big link to her Ants movie in there. No mention of me, though. Sigh. I love this photo of James, though:


James Traniello in Concord, Massachusetts, where he and colleagues dig up ant colonies to take back to the lab to study ant brain development. Photo by Vernon Doucette

It’s an unlikely starting point for neurobiology research, but James Traniello is in the woodsin Concord, Massachusetts, striding along paths trod by Thoreau. Sweet fern perfumes the air and the ubiquitous Queen Anne’s lace pokes up its white flowers along the side of the trail, even as the Route 2 traffic noise buzzes through the woods. Traniello finds what he is looking for, tell-tale signs of the ant species Pheidole pilifera: tiny piles of seed hulls at nest entrances. It’s warmer on the sun-drenched trail than it is in the woods, so ants build their homes underneath it.

Traniello (CAS’74), a College of Arts and Sciences professor of biology, comes here with his students and colleagues to dig for living colonies of P. pilifera to take back to his lab on Cummington Street. They excavate the nest, suck the ants up with an aspirator, then sort them out, making sure they have the queen, essential to keeping a colony alive.

Almost all ants in a colony are sterile workers and sisters, with assigned roles from nurse to nest keeper to forager to soldier. Traniello wants to know whathappens in ant brains that leads to behavioral specialization. Until recently, scientists didn’t have the tools to even begin answering this question. But with new imaging techniques and neurochemical analyses, the sociobiology of ants is becoming clearer.

Now, with help from a nearly half-million dollar grant from the National Science Foundation, Traniello and his colleagues are trying to discover the neurological basis of ant behavior, and by looking at several different species at the same time, they also hope to understand the evolution of the structure of ant brains. These aren’t just idle questions: Edward O. Wilson, one of Traniello’s doctoral advisors at Harvard, has famously suggested that ant behavior is helpful in understanding the behavior of certain upright biped creatures as well.

Read the rest of the article here.

Eye structure in Bullants correlates with the timing of foraging bouts

Ever wondered about what goes on in the enormous eyes of Bullants? Yup we did too, and we ended up finding that the diameter of the photoreceptor, the optical sensitivity, the number of facets and the facet sizes, all increase gradually from diurnal to diurnal/crepuscular, crepuscular/nocturnal and nocturnal species. Such adaptations in eye structure within a single genus, the primitive ant genus Myrmecia especially, is truly remarkable.

Read more here:
Greiner B, Narendra A, Reid SF, Dacke M, Ribi WA, Zeil J. 2007. Eye structure correlates with distinct foraging bout timing in primitive ants. Current Biology 17 (20): R879-R880.

Wednesday, October 17, 2007

6 badass scientists

Via Ontogeny:

I'll give you the short list...Bayblab can fill in the details of why they chose them:

1. Craig Venter
2. Richard Feynman
3. Andrei Dmitrievich Sakharov
4. Dr. Duncan Steel
5. Stephen Hawking
6. Meredith Charles Gourdine

No women? Hmm. I can think of a significant renegade who happens to be a woman: Barbara McClintock

I agree. Hey -- what about me? I'm a scientist and I play roller derby. How much more badass can you be? Of course I'm not famous or anything (or very good at roller derby), but maybe one day...
How about that guy who was bitten by a poisonous snake and sat down to record the effects of the poison as it slowly killed him. That is pretty badass. Does anyone know who this guy is?

Friday, October 12, 2007

"The Hive" Starring Tom Wopat-World Premiering This Month on VOD

So I got this email from someone named Erica telling me about this new movie coming out on VOD called "The Hive." She seems to work for RHI Entertainment. I can't actually watch this movie as I don't even have basic cable, but it does sound like a lot of fun:
The Hive is a horror-thriller that features a mass of 200 flesh-eating army ants making its way through the jungles of Brazil devouring every living thing in its path. Called in to stave off the attack is Horace Lennart, a scientist from Thorax Industries extermination service in Los Angeles, and his girlfriend, entomologist Claire Dubois. But when they discover the bizarre intention and origins of the crawling creatures, they fear for the future of the planet.
I went to IMDB and found this user comment on the movie from someone named david, from glasgow, scotland.
For me, if you start with a premise of killer ants you cant go far wrong but throw in aliens, babies being eaten, dialogue like "im not here to have a conversation with an ant" and you're moving into true cult status.
Add to the mix ants who form themselves into fists and knock over trees and how good does this film sound? And you haven't even seen the cool weapon the good guys have!
You could argue that its not the best acted movie in the world but I don't think awards ceremonious were on anyone's mind when storyboarding this one.
If you think say "the swarm" is a poor movie then this maybe isn't one for you but if you've ever lay awake at night wondering how ants would build a computer then this is the only place i know where you might just find out!
Like I said, sounds like fun. If anyone sees it, let me know how it is.

Thursday, October 11, 2007

Ant-Aphid Mutualism Gets Weirder

From Ontogeny (via Nature):
The strange symbiotic relationship between ants and aphids has been made even more interesting by a new discovery. It has previously been shown that the ants – which ‘milk’ the aphids for a sugary liquid – will chew off and chemically retard development of aphid wings to keep them nearby. Now it seems that they also dope them up so even if they try to run away they don’t get far (The Daily Telegraph).

“Although both parties benefit from the interaction, this research shows is that all is not well in the world of aphids and ants. The aphids are manipulated to their disadvantage: for aphids the ants are a dangerous liaison,” says Vincent Jansen of Royal Holloway university (Press release)

The researchers found that aphids walking on filter paper travelled much slower when the paper had previously been walked on by ants than they did on plain paper. And when placed on dead leaves – which they should try to leave in search of food – having ants around significantly slowed aphid departure. “We believe that ants could use the tranquillizing chemicals in their footprints to maintain a populous ‘farm’ of aphids close to their colony, to provide honeydew on tap. Ants have even been known to occasionally eat some of the aphids themselves, so subduing them in this way is obviously a great way to keep renewable honeydew and prey easily available,” says Tom Oliver, of Imperial College London (press release).

You can access the journal article here.

Tuesday, October 09, 2007

2007 Ig Nobel Awards

One of the best things about living in Boston is that I can do things like attend the Ig Nobel awards. You know you're jealous. Some of my favorite awards this year:
  • LINGUISTICS: Juan Manuel Toro, Josep B. Trobalon and Núria Sebastián-Gallés, of Universitat de Barcelona, for showing that rats sometimes cannot tell the difference between a person speaking Japanese backwards and a person speaking Dutch backwards.
  • REFERENCE: "Effects of Backward Speech and Speaker Variability in Language Discrimination by Rats," Juan M. Toro, Josep B. Trobalon and Núria Sebastián-Gallés, Journal of Experimental Psychology: Animal Behavior Processes, vol. 31, no. 1, January 2005, pp 95-100.
  • ECONOMICS: Kuo Cheng Hsieh, of Taichung, Taiwan, for patenting a device, in the year 2001, that catches bank robbers by dropping a net over them.
  • REFERENCE: U.S. patent #6,219,959, granted on April 24, 2001, for a "net trapping system for capturing a robber immediately."
  • MEDICINE: Brian Witcombe of Gloucester, UK, and Dan Meyer of Antioch, Tennessee, USA, for their penetrating medical report "Sword Swallowing and Its Side Effects."
  • REFERENCE: "Sword Swallowing and Its Side Effects," Brian Witcombe and Dan Meyer, British Medical Journal, December 23, 2006, vol. 333, pp. 1285-7.
  • CHEMISTRY: Mayu Yamamoto of the International Medical Center of Japan, for developing a way to extract vanillin -- vanilla fragrance and flavoring -- from cow dung.
  • REFERENCE: "Novel Production Method for Plant Polyphenol from Livestock Excrement Using Subcritical Water Reaction," Mayu Yamamoto, International Medical Center of Japan.
  • PRESS NOTE: Toscanini's Ice Cream, the finest ice cream shop in Cambridge, Massachusetts, created a new ice cream flavor in honor of Mayu Yamamoto, and introduced it at the Ig Nobel ceremony. The flavor is called "Yum-a-Moto Vanilla Twist."
And, for someone who is constantly annoyed by inconsistency, I give a hearty hat tip to Glenda Browne of Blaxland, Blue Mountains, Australia, who channeled her annoyance into a published paper and an Ig Nobel!
LITERATURE: Glenda Browne of Blaxland, Blue Mountains, Australia, for her study of the word "the" -- and of the many ways it causes problems for anyone who tries to put things into alphabetical order.
REFERENCE: "The Definite Article: Acknowledging 'The' in Index Entries," Glenda Browne, The Indexer, vol. 22, no. 3 April 2001, pp. 119-22.
My husband's favorite attendee, of course, was Francis Fesmire, of the University of Tennessee College of Medicine, for his novel treatment of intractable hiccups with digital rectal massage. This guy is way too into his award (see photo at right for proof). After the ceremony, he even threw out free Dr Fran's Anti-Hiccup Kits, containing his picture, a latex surgical glove, a tube of jelly and directions. Tim was able to snag one and we are contemplating appropriate methods of display. My suggestion: put it in a glass box with a sign on the front that says "In case of intractable hiccups, break glass" and attach a tiny hammer.

Curators’ Favorites

Via antomatic:

The Washington Post ran a special “Museums” section on October 7th, and in the featured article, “Curators’ Favorites: No Cookie-Cutter Ideas Here” they asked local curators what some of their favorite objects are. This article met the definition of being phoned-in in every sense of the phrase. All is forgiven, however, since they published the pick of Ted Schultz, research entomologist and chairman of the Department of Entomology, National Museum of Natural History:

Looking at a 20-million-year-old ant trapped in amber.

Such ants grew fungus gardens inside their colonies. This ant, found in the Dominican Republic, is less than 3 millimeters long.

“I always thought these fungus-growing ants, the agricultural ants, were the coolest organisms I’d ever heard of. This one was climbing up some tree 20 million years ago and the resin from the tree oozed out and trapped it.

“These ants, some of them live in trees, some of them climb up in trees to get stuff to go back and plant their garden on. These get seeds or little flower petals or caterpillar poop and other kinds of organic detritus. They might be wandering up the tree getting that stuff — and that’s what this one was doing. I think a lot about what was the ancestor of all fungus-growing ants like? How did it discover agriculture? What was it doing before? If I knew what it was doing before I might be able to figure out how it wound up cultivating fungi.

“For biologists that work in a museum, who look at specimens all day, who go out and collect things, it’s a largely visual, aesthetic kind of undertaking.

“For us humans and mammals, the soft tissue is all on the outside and the hard bones are all on the inside. For insects, the soft stuff is all on the inside, and the outside is sculptured. It’s hard sculpture. We become connoisseurs of these miniature sculptures.”

Wednesday, October 03, 2007

Serial monodomy in ants: an antipredator strategy?

Ecological Entomology

Vol. 0 Issue 0 Page ???


Abstract. 1. The term serial monodomy is used to describe a life-history phenomenon in social insects. Serially monodomous colonies maintain multiple nests for their exclusive use, but only occupy one nest at a time.

2. The hypothesis that colony odours mediate nest relocation decisions was tested in the serially monodomous species Aphaenogaster araneoides from Central America. Odour extracts of colony members were created using a non-polar solvent.

3. Colonies strongly avoided reoccupying nests treated with colony odour extracts, while control colonies often returned to nests subjected to solvent-only control. Behavioural observations indicated that A. araneoides colonies are capable of detecting army ant (Eciton burchellii) raids up to 1.4 m from the raiding front, with several seconds to evacuate nests.

4. It is proposed that the function of serial monodomy in A. araneoides is the reduction of nest odour to enhance detection of predaceous army ants. Serial monodomy may be a widespread but undocumented mode of nesting where army ants occur in tropical and subtropical climates.

Monday, October 01, 2007

Effects of Drugs and Alcohol on Spider Webs

I knew I should have studied spiders! It's ridiculous what kind of crappy research is getting funded these days. (thanks for the link, Dan!)