I think you are alluding to lichens in your statement about Hi Aabir, I think you are alluding to lichens in your statement about fungal/cyanobacterial neurotoxins, right? If so, I think you are referring to microcystins many species of Peltigera but they aren't "sit and wait" predators. Rather, the microcystins are hypothesized to function as an antiherbivory mechanism.
I think lichens are a good example of what you are asking about, where association of two taxa creates new, unexpected functional traits that likely expans the fundamental niche of both taxa, although we usually only infer the niche expansion. Lichen growth forms are good example. They have a huge variety of surface area to mass ratios determined by their gross morphological form, which is strongly related to moisture regulation, as they are poikilohydric. At the same time, the photobionts ability to restart photosynthesis upon rewetting is controlled by the physiology of the photobiont. So, even if the lichen growth form allows quick rewetting, if the photobiont is cyanobacterial, the lichen will have a slower photosynthetic recovery in comparison to the same lichen with a green algal photobiont. This can be seen in what are called "photomorphs", where the same fungus switches between an green alga and cyanobacterial partner. The morphology is completely different, one looking like a dark, filamentous fruticose form (cyanobacterial) and the other a large, flat, leafy foliose form (green algal form). Many of the classical evolutionary patterns (eg. convergence) occur within these interplaying contraints to make similar functional traits (eg. Muggia, L., P. Nelson, T. Wheeler, L. S Yakovchenko, T. Tønsberg, and T. Spribille. “Convergent Evolution of a Symbiotic Duet: The Case of the Lichen Genus Polychidium (Peltigerales, Ascomycota).” American Journal of Botany98, no. 10 (2011): 1647–1656.). -Peter ________________________________ From: Aabir Banerji <[email protected]> To: [email protected] Sent: Friday, September 6, 2013 8:55 AM Subject: Re: [ECOLOG-L] "Emergent" functions contributing to the functional diversity of a community? Hi, Jen. Part of what inspired me to ask this question was a conversation I've had with some local microbiologists. They, like the folks in Tamar's group, have apparently been doing comparative studies on microbial communities from different regions. They had told me that a few of the communities lacked mercury-resistant species, based on there being no sign of the genes that are known to produce mercuric reductase in any of the samples. This sounded to me like affirming the consequent, so I asked them if biofilms or consortia couldn't yield something equivalent to mercuric reductase. The answer was no. As you say, there's lots of literature on facilitation/symbiosis enabling species to survive and do stuff in places where they'd never be able to make it alone. This is interesting and surprising enough, all by itself, and definitely contributes to communities being more than the sum of their parts. But my point is that, even if you only look at each partner separately, you would probably still have a guess as to what they can make happen in the community once they're there (e.g., photosynthesis, N-fixation). You would not expect a cyanobacterium and a fungus to combine their respective enzymes into a neurotoxin and act like a sit-and-wait predator... yet perhaps less dramatic versions of this kind of thing happen often (and predictably) in complex communities. ~ Aabir ----- Original Message ----- From: Jenn Adams Krumins To: Aabir Banerji Sent: Fri, 06 Sep 2013 13:31:30 -0000 (UTC) Subject: Re: [ECOLOG-L] "Emergent" functions contributing to the functional diversity of a community? Hey Aabir, I think you are looking for something very sophisticated when something very simple will do. I the plant soil world - this kind of facilitation is everywhere. Legumes... mychorrhizae etc. Look into that literature. The presence of myccorrhizae does not only benefit the host plant. there are networks - then it gets more interesting because one plant is paying with the others are reaping the rewards.... hope all is well for you over there - Jen On Fri, Sep 6, 2013 at 5:57 AM, Aabir Banerji <[email protected]> wrote: Hi, Martin. Thank you... but this isn't quite what I'm looking for. This is an (awesome) example of what I meant when I referred to a species gaining access to a new niche via the product/ability of another species (the parasite gaining the ability to lure in and feed on its definitive host by using its intermediate host as bait). Even if the parasite happens to induce a novel morphology in its intermediate host, it won't generate a new process in the system or give us reason to reclassify the parasite into a new functional group. Here's a potential example that I was sent yesterday: http://en.m.wikipedia.org/wiki/Anaerobic_oxidation_of_methane. If the relevant microbes have to make a combination product to do the job, and neither can do so by itself, it means that AOM is an emergent function. Another potential example (what I had in my head when I referred to neighborhood habitat amelioration) would be if dry-climate plants become drought-resistant by developing a water-retentive rooting pattern in mixed-species aggregates that they could not develop in monoculture. In this case, drought-resistance is an emergent function. I hope this is clearer. Best regards, Aabir ----- Original Message ----- From: Martin Meiss To: Aabir Banerji Cc: Ecological Society of America: grants, jobs, news Sent: Thu, 05 Sep 2013 21:25:04 -0000 (UTC) Subject: Re: [ECOLOG-L] "Emergent" functions contributing to the functional diversity of a community? Would you consider this to be an example of what you're looking for: How about a parasite that needs an intermediate host before infecting its main host. Perhaps a worm that must live in a snail which must be eaten by a vertebrate before the parasite can enter the vertebrate to reach its adult form. Martin M. Meiss 2013/9/5 Aabir Banerji <[email protected]> Dear fellow ECOLOG users, The relationship between functional diversity and taxonomic diversity in ecological communities isn't always linear. I imagine the simplest case of non-linearity is where there is a lot of functional redundancy among phylogenetically diverse taxa. The opposite extreme (a depauperate community having a lot of functional diversity) is also possible... e.g., where generalist populations exhibit complex demographic structures or inducible polymorphisms. What I'd like to know, though, is if there is evidence of taxa fulfilling functions by associating with one another. It's one thing for a species to enter a new niche by relying on the product or ability of a different species (such as a beneficial symbiont). It's another for different species to combine complementary products or abilities to create/achieve something that no one species in the community is able to produce or achieve by itself (an "emergent" function). This latter phenomenon would be something akin to neighborhood habitat amelioration... or, perhaps, something more general that includes neighborhood habitat amelioration. Would any of you happen to know of recent reviews or articles that address this topic? Or some really good examples of it, perhaps? Thanks in advance! ~ Aabir Dr. Aabir Banerji Postdoctoral Associate Institute of Evolutionary Biology and Environmental Studies University of Zurich [email protected]
