What is a species? And why care?

What is a species? A nice rule of thumb is that a group of organisms that can produce fertile offspring together is a species. And as long as you are dealing with nicely large, long-living, accessible species like cats and horses that will do. But what if you are dealing with organisms whose reproduction has never been observed? And why would it matter?

It helps to define species, even if you can’t be too sure of whether you’re actually getting it right. If I say I saw a picture of a dragon, you will all have an idea of what I saw, even though nobody could possibly conclusively define a dragon. If people know what you mean a lot is won. The same holds in micropalaeontology.

Micropalaeontology is the study of microfossils; the preserved remains of micro-organisms. An example of a group of such microorganisms is foraminifera; unicellular organisms that live in the sea, and produce little shells. That shell is what can remain preserved when the organism dies: the microfossil. They tend to be 0.1 to 1 mm in size. Their use in environmental science is endless; they are widespread and abundant, and there are many different species with each their own environmental preferences. Their evolution is fairly well-studied as well; if you show a micropalaeontologist a handful of foraminifera, he or she can most likely tell you, after barely more than a glance, how old they are, and what environment they lived in. And even their little shells can be studied; they can hold a wealth of information.

An example of an assemblage of foraminifera; in this case form Myanmar/Burma. Picture: Psammophile. Source: Creative Commons.

But back to the question of subdividing them into species. Traditionally, species have been defined on the basis of shape. Later, when more information became available, environmental preferences were taken into account as well. The whole classification of species was episodically revised, based on new information; the result was an ever-changing system, where not everybody used the same version. But everybody knew that; as long as you knew what classification someone used you knew, more or less, what you were up to. But a certain level of subjectivity cannot be avoided. Not every specimen looks like a textbook figure. But in spite of its confusions and imperfections, the system worked.

And then DNA analysis was invented. Suddenly, it could be objectively determined if organisms belong to the same species or not. And it is done on foraminifera too. When there was a workshop on foraminifera taxonomy (species classification), the researchers working on foraminifera DNA decided to put the old system to the test. They provided the participants of the workshop with 40 pictures of foraminifera of a specific genus of which they had sampled the DNA: they therefore knew which of these belonged to the same species. And now they asked us to group them the old way, and tell us what name they would give these species.

These are specimens of Ammonia beccarii; a species that has sometimes been subdivided into various species, but of which DNA research has revealed that it is indeed only one. Photo: Hans Hillewaert. Source: Creative Commons.

The first thing that became apparent was that it wasn’t an easy job. Every group of experts struggled! And every group came up with slightly different results. And the names assigned to the species did not always match either. That is a measure of the mentioned flexibility in classification, and subjectivity. But then they were shown what the DNA had revealed.

Some results were as expected. Sometimes the old-fashioned method split a species into two different ones, or left a specimen out that looked odd, but that is all within expectation. But there were shocks too: some species turned out to contain specimens that look quite different, and that none of the participants would have considered to be the same species, if they would find them in their samples. That provided food for thought.

Foraminifera pictures taken with a Scanning Electron Microscope; the top left is classified as an Ammonia beccarii, like the specimens in the picture above. And according to the USGS, the top right is an Elphidium excavatum forma clavatum, but are they sure? This was one of the species that created some confusion in the "shape vs DNA" game... 

Does this mean we have to forget about micropalaeontology? No; as flawed as the discipline is, it still answers (and raises!) very relevant questions. And it helps to know how big the uncertainties are. Does this mean we have to now sample the DNA of all foraminifera we study? No; that would be too time- and money-consuming, and beside that; most of the specimens we study are long dead, and don’t contain DNA anymore. So what is the relevance of this work?

To give you an idea of how confusing it is: one of these pairs are two specimens of the same species, but the other pair is two different species. I'm not going to say which is which, but I think it illustrates similarity isn't enough to decide. 

One of the things DNA research can do is tell the micropalaontological community which differences in shape are indicative of a different species, and which are just variation within a species. They could improve on their classifications that way. The research can also help in cases where a species seems to be able to adapt to very different environments; can they really, or are we dealing with several species that look the same? Knowing that would tell us something about the adaptability of marine species; quite useful knowledge in these times of rapid change. Various experts probably already have a long list of further questions they would like to see answered, and the process of answering will create a multitude of new questions. It’s even possible we’ll see new species evolve into existence right under our eyes…

North Carolina and the sea - an update

Is North Carolina asking citizens to think for themselves? Regulations, put in place with the best intentions, often turn against their purpose. Think of regulations that limit the height of the ladders window cleaners are allowed to use in their work; the idea behind them is increasing the safety of those who clean windows. But it results in window cleaners having to resort to scaffolding or boom lifts more often; this makes their services much more expensive. With the result that people will try to clean their own windows. Without the experience that comes with the profession. This law is reported to only have resulted in an increase in window cleaning accidents… And boom lifts aren’t fail-proof either; I found seven cases of death and 19 of injury due to boom lift in the Netherlands since 2003.

Source: Aubrey Dale, Creative Commons

So well-meant laws often have a reverse effect. But could it work the other way? As I wrote in a blog post in early June; North Carolina was considering making it unlawful to base coastal protection policies on up-to-date sea level change research. This law didn’t make it; the House of Representatives have voted for its revision. The new version, which will have to get an OK from the governor before it becomes a law, contains the clause that the Coastal Resources Commission shall direct its Science Panel to actually study scientific literature, and come up with recommendations only after that. They have until December 2015 to write the report. So the threat of North Carolina making it unlawful to be informed about sea level change is gone. On the long term, that is. The new version also contains a clause that says, and I quote, “The Coastal Resources Commission and the Division of Coastal Management of the Department of Environment and Natural Resources shall not define rates of sea-level change for regulatory purposes prior to July 1, 2016.”

An example of coastal erosion from California

Science (the magazine) considers this bad news; those who wish to know if it’s wise to build a new house somewhere on the coast get no guidelines from their state for the next four years. But it also means they are allowed to think for themselves. If policy makers are forced to give out meaningless guidelines, it may well go unnoticed by the consumer of these guidelines that these are completely detached from reality. But when the state publicly announces silence on the topic, people will be quite aware they have to find out for themselves. And not everybody will be pleased that they pay their tax, but still have to spend time on making their own guidelines; and some people will undoubtedly find incomplete or inaccurate information in their search, but altogether I think it’s a much better situation than one in which it is downright illegal to do the sensible thing. So this revised law is a watered-down version of a law aimed at keeping the people ignorant; this version may serve to make them better informed that they were before!

Carbon dating

If you find an ice man on a mountain pass, or a mammoth in the permafrost, or the remains of a prehistoric building, and you want to know how old they are, what do you do? You carbon date it. Bob’s your uncle! We use carbon dating too, for dating the sediments we use for our sea level reconstructions. When you read something in the newspaper about carbon dating you are likely informed of the uncertainty. But is that all there is to it? And the answer to questions like that tends to be: no, it’s complicated. And it is. I thought it was worth it to elaborate; sometimes a scientific claim relies heavily on the age of something or other, and quite often that age is determined with 14C.

So how does it work? There is a lot of nitrogen in the atmosphere, and that gets bombarded with cosmic rays. Sometimes an incoming neutron will smash a proton out of a nitrogen atom, making it a 14C atom. Carbon generally has mass number 12; if it does, it is stable, which it also is with mass number 13. This latter isotope is used in all kinds of studies, e.g. reconstruction of the diet of extinct animals. 13C is unevenly distributed over potential food sources, and the enamel of the teeth bears witness to the 13/12C ratio of the animal’s food. But that is another matter.

14C is unstable, and will turn back into nitrogen. Everything that breathes will constantly replenish its 14C. As soon as it dies, though, it will not get any new 14C into its system, and that’s the moment the 14C clock starts ticking. I know of a cartoon where a granddaughter reassures her grandpa it doesn’t matter if he forgets his age; they can have him carbon dated! But that cartoonist hadn’t understood the process...

14C has a half-life of 5730 years. Modern equipment is sensitive enough to detect a signal even after 10 half lives; so on a good day, you can date things as old as 60.000 years. The complicating factor is that you need not only know the half life of your isotope, but also the initial concentration. And that’s harder. Unfortunately, the sun is not constant in its output of radiation. And that gives rise to ambiguities: if you measure a certain 14C activity in a sample, it might sometimes derive from either a not that remote time where solar activity was lower, or a more remote time when solar activity was higher. It’s clearer to see that from the calibration curve, which links “radiocarbon age” (the age calculated as if 14C production was constant) to the “real” age (corrected for solar variations). If you look at that calibration curve from a distance it looks like straight line. But if you come closer, and zoom in to the last, say, 1000 years, you’ll see it  has some peaks and troughs, meaning some radiocarbon ages can equate to more than one calibrated age.

A recent version of the calibration curve; the IntCal 2009 version. Data from Reimer et al (2009); full reference below. The small graph is a blow-up of the last 1000 years. An interesting article on the construction of a calibration curve is Fairbanks et al., 2005; full reference below.

An example of an ambiguous 14C calibration. The last few hundred years are difficult to date with 14C, as the calibration curve there has lots of wiggles. So this sample with a radiocarbon age of ~200 years could, if no other information is available, be from 1657 as much as it could be from 1936. The calibration program used here is OxCal; reference below.

If you have several 14C dates in sequence, you can sometimes solve this issue. If you, for instance, have a sediment core with two 14C dates in an interval with a spike in the calibration curve, then you know it can’t be the case that the upper one is from the older limb while the lower one is from the younger limb. Your younger sediments must be overlying the younger ones! And if you have a whole lot of them, some solutions are more likely than others. And in order to find the most likely result scientists commonly resort to age modelling software. That tends to draw all possible time lines through your dates, and calculate the probability of every one of them, in the end giving you a (range of) most probable age model(s).

An example of making an age model from a number of 14C dates, some of which ambiguous; we here have a sedimentary core with 8 hypothetical 14C samples (blue dots). The 14C age of these is given to the right of the core; at first glance they don't look too good, as some of the samples give the same 14C age, though being from a different depth. On evaluation of how these could be plotted on the calibration curve, though, it becomes clear a rather plausible age model can be made. The proposed interpretation is given to the right of the 14C ages next to the core, and as red dots on the graph. I added a few orange dots where alternative interpretations are possible. The age vs depth plot below shows why these were not chosen; pronounced shifts in the rate at which the sediments of this core accumulated are needed to explain these solutions.

So even if you have fine 14C dates, you might not be able to assign unambiguous ages to them. Things get worse if the samples on which the 14C measurement was done in the first place were flawed. Two things specifically need to be looked out for: contamination and misplacement. Contamination is easy to picture: say you are dating a very old piece of wood, but there’s a modern wood louse in it. Your date will come out younger than the age of the wood. Radiocarbon laboratories luckily clean the samples they get sent very thoroughly, so in practice contamination will not lead to big errors.

When you want to know the age of, say, a bog body, sampling is quite straightforward. You sample the body and date it. If you want to know the age of sediments, though, you can run into the problem of misplaced samples. You want to find something datable that is representative for the surrounding sediment; something that died there and immediately got deposited with the sediment. A plant leaf that falls down, for instance. But If a beetle burrows down into the mud, and dies there at 20cm depth, it will not reflect the age of these 20 cm deep sediments. The same with roots. They grow down from the surface, and might have died by your hand while embedded in, say, 2000 year old sediments. Careful selection therefore is key.

Examples of what a 14C sample may look like: on the left, a leaf as it appears in a sediment core, and on the right the shield of a non-burrowing weevil after it has been taken out of the sediment and cleaned.

So where does that leave us? In nuance, of course. If a study mentions its reliance on 14C dating you only know how robust that was if you get to see how many dates they had, what exactly they dated, how accurate the measurements were, where they plot on the calibration curve, and how an age model was constructed with that. In a peer-reviewed publication that information would normally be given, unless it’s in a condensed journal such as Science. I know from experience that the range of robustness of the age model in published articles is very large. So after all that, maybe it will be a bit more understandable that scientists often refuse to reflect on any new scientific result until they’ve spelled out the actual source. It might make us very slow in our judgement, but hopefully quite thorough as well! And that may well be an approach that, when used by more people, could well make a difference...

References:

Bronk-Ramsey, C. (2010). OxCal Program v4.1.5. Radiocarbon Accelerator Unit, University of Oxford.

Fairbanks, Mortlock, Chiu, Cao, Kaplan, Guilderson, Fairbanks, Bloom, Grootes, and Nadeau: Radiocarbon calibration curve spanning 0 to 50,000 years BP based on paired 230Th/ 234U/ 238U and 14C dates on pristine corals. Quaternary Science Reviews 24 (2005) 1781–1796

PJ Reimer, MGL Baillie, E Bard, A Bayliss, JW Beck, PG Blackwell,  C Bronk Ramsey, CE Buck, GS Burr, RL Edwards, M Friedrich, PM Grootes,  TP Guilderson, I Hajdas, TJ Heaton, AG Hogg, KA Hughen, KF Kaiser, B Kromer,  FG McCormac, SW Manning, RW Reimer, DA Richards, JR Southon, S Talamo,  CSM Turney, J van der Plicht, CE Weyhenmeyer (2009) Radiocarbon 51:1111-1150.

The solution to sea level rise

Imagine the sort of country in which a threat is dealt with by the highest authorities by making it illegal to consider this threat. Let me guess; you are now picturing some Orwellian world. No need for such exoticism, I’m afraid! Just picture North Carolina. And I’m not joking.

North Carolina has a rather long coastline, with extensive coastal plains behind it. At many locations, the coastline  is eroding (look here for an interactive map). You would think a state like that is most interested in the latest developments in sea level research. You would want to know what the chances are of what areas being flooded or eroded away, right? If you have a coastal settlement, or are considering to build one, you would want to know how expensive it will be to defend it against the sea. If you may want to buy a house, you would want to know if it will be toppling into the sea within a few decades. But no.

North Carolina and its topography

What North Carolina wants is to ignore the problem and hope that that will make it go away. A bill has been proposed (Replacement House Bill 819; read it here yourself; it's hilarious!) which makes it illegal to try to accurately predict sea level rise. It also makes it illegal to adopt policies, rules or guidelines based on educated sea level predictions. You have to hand it to the Americans: they do think outside the box sometimes. So far out you are surprised any adult would be willing to admit to such thoughts.

So what will they base their policies on? If this bill will be passed, it will only be legal to make sea level predictions by linearly extrapolating sea level change since 1900. So that’s sorted then! The sea will surely be so polite as to take heed of such legislation. Those who want to live near the sea are best off to do so in this enlightened state; in other states, the sea might very well do what she pleases!

 So far the sea has not refrained from jeopardising property: coastal erosion at Cape Hatteras, NC. Picture: Gary Braasch, taken from the BBC website.

If this bill is passed it may set a precedent; I can see more problems being tackled. I can see a law in predicting economic growth (or shrinking). Only extrapolations from the last month could be allowed! That will sort the economy out.

But jest aside; evidently a bill like that can be proposed. And if you can propose a bill that makes it illegal for authorities to inform civilians about sea level rise, and protect them against it, then what else can you propose? There are many other things one would hope local and regional authorities protect their citizens from; can all of that be made illegal at the whim of someone with a vested interest and a big mouth? I sure hope the answer is no...



Standing up for Science

“We try to get it right, and we are generally nice people!” If people feel the need to confirm this something is probably wrong. So who was saying this to whom? It was a science journalist in front of a room full of scientists. They should be the best of friends; science journalists wouldn’t have a job without scientists, and scientists would struggle to get their work noticed by society without the science journalists. But a lot of mistrust hangs over this collaboration.

Where did this attempt to bridge the abyss take place? At a course on science communication “Standing up for Science”, organised by “Sense About Science”. The latter is a charity aimed at helping scientists to get their message across, and helping the community to find the scientific support it needs. They were approached, for example, by an organisation of fire fighters, who were worried about clambering around on roofs just next to phone antennas. Would the radiation pose a threat? If one asks internet one can get all sorts of loudly proclaimed opinions, but who to trust? Sense About Science will show you the way!

The glamorous venue at Belgrave Square, kindly provided by the Society of Chemical Industry

Another of their actions has been to write a flyer on the peer review process. For those unfamiliar with it; it is the selection process scientific manuscripts go through. If you send one to a journal, the editor will ask a few fellow experts in the field to review your manuscript. They can recommend publication as is, revision, or rejection. The editor has the final say. As scientists have something to lose by letting standards slip, this process tends to be very thorough. Sense About Science has explained it a bit better than I just have. They point out the merits, but also the weaknesses of this process. And explain the relative merit of peer-reviewed sources compared to other sources. And they have sent 1/2 million copies out in all directions, making it a part of civil service training and a school resource. One could assume many lay people would not be aware of this phenomenon, and might make the mistake of equating proper scientific literature with, say, any polemic in a blog. They also sent a flyer about statistics and how to make sense of them to it to all MP's and lords in the houses of parliament! And I don't know how many of these flyers have gone linea recta into the waste paper bins, but every single one that is read and taken heed of is a major triumph.

At this occasion they had organised a workshop for early career scientists to give them some advice of getting their message across. In order to do that they had invited three panels of experts: one with researchers who had lots of experience with the media, one with science journalists, and one with people such as media officers.

One of the researchers, Steve Keevil of (among others) King’s College in London, had a fascinating story to tell. He was involved in MRI science; something evidently very societally relevant. His field was shaken up when an EU directive would become effective which would seriously limit the use of MRI. All with the best intentions, but in effect severely limiting the diagnostic methods available to the medical profession. He had alerted some powers that be, but these had just said he had to live with it. EU directives are irreversible!

The panel of researchers. With Steve Keevil talking

He had then contacted Sense About Science. They had advised him to send out a press release and hold a press conference. He thought they had gone mad! But he did it. And it caught the attention of the public. And through that, it caught the attention of politicians. Before he knew it he was on a panel that advised parliament. That EU directive has been postponed more than once. And is likely not to be passed at all. Victory!

The journalists, after reassuring us they’re not trying to stitch us up, also had interesting stories. One lady working for science programmes on the radio (Michelle Martin) said she often phones scientists to see if they are willing and able to collaborate on a programme. And that phone conversation is the dress rehearsal. So scientists; don’t save your brilliance for the actual interview; if you do that it may not come!

The last panel included a lady from SAS itself. She encouraged us to become a member of their network “Voice of Young Science” (VoYS); the people they call on if they get a request from the public. They always have use for more people! And it is a great chance to now and then really make a difference. I was glad to hear that you don’t actually have to be below any specific age to join...

A selection of publications SAS has produced

With all these panels the room had lots of discussions, and between these sessions there were group discussions of only the scientists. It was great to hear all these things, get all sorts of new ideas (I’ll start tweeting! And join VoYS! ) and make contacts with all these other people out there who are interested in science communication.

My last question was if someone had a tip on how to deal with aggressive comments. One quite regularly bumps into climate sceptics who think all scientists are part of some nasty conspiracy, and they are not particularly keen on listening to a balanced scientific argument. It’s all part of the conspiracy, right? A Danish girl stepped in there, and said she had witnessed an astronomer being interrupted by someone saying “but the moon landing, that was all fake, wasn’t it?” The astronomer then didn’t open a register of scientific publications based on the moon landing; he just said “if it was fake, don’t you think the Soviets would have found out, and loudly exposed this scam?” I should keep that answer in mind...

How to make a sea level record

“So how do you know how high sea level has been in the past?” I get that question a lot. It’s a good question; if you’re not a sea-level scientist (because that’s cheating) you might wonder how something as elusive and evanescent as sea level could be traced back in time. One may think of marine features above the reach of modern tides such as raised beaches, or coral reefs, or signs of wave erosion, such as wave notches. And as signs of sea levels having been lower one can think of drowned ruins. But these are all isolated indicators. What if you want to know what happened over a long period of time?

A fossil coral reef in a forest, which is clearly a terrestrial environment; a clear indicator of relative sea level having been higher in the past. Picture taken in Windley Key Fossil Reef Geological State Park

 

When geologists and geographers want to have a continuous record of something they often stick a corer into the ground.  If you pick the place where you do that right, you get a core comprised of sediment that has been deposited over the time period you are interested in, and contains the information you need. So just suppose you want a sea level record that goes back 500 years, how would you go about that? You need to find a place near current sea level where sediment has been deposited in a calm environment for quite a while, and where there are things in the sediment that record the position of the sea. Think about it: not many places will do. Many coasts are erosive. Many are energetic. Many just contain sand, with dead shells, that have washed ashore. So what did the scientific community come up with? The salt marsh.

 A salt marsh

A salt marsh is an environment that gets flooded periodically by tides, and where salt-tolerant plants grow, trapping sediment. If sea level rises slowly, they can build up; if it drops slowly, they can build out, provided there is space for that. If sea level changes too fast the marsh will become either a fresh-water environment, or drown.

On the surface of salt marshes not only plants grow; they tend to host a plethora of micro-organisms too. Among these are foraminifera and diatoms. Foraminifera are small animals that build a shell, either of calcite or of particles they find. Diatoms are algae that build a kind of shell from silica. And there are countless many species in either group. And all of these species have their own preference for how often they are in the water and how often they are dry, and how salt the water is they live in, and many more of these factors. In other words: they are picky about where they live with respect to sea level. And the good thing is: they take that pickiness with them into their graves. The organisms themselves decay, but under favourable circumstances their shells are preserved. Ready for a passing geographer to interrogate…

A sediment core from a salt marsh

What we do is roughly as follows: we take samples from the surface of the marsh over a transect from high to low. We also take a core, trying to get the location right so that the entire period of interest is preserved in its sediments. Using surveying equipment we find out at what elevation these are all taken from.

Later, in the lab, we determine which species of the microorganisms of our choice we find in the surface samples, and their absolute and relative abundance. That tells us at what elevation the various species live. Then we determine the species assemblages in samples taken from the sediment core. Given that we have established at what elevation interval these species live we then know at what elevation these samples must have been deposited. And if we, for instance, take a core and find an assemblage typical for an elevation of 30 cm above sea level at half a meter down in the core, we know that when these sediments were deposited sea level was 80 cm below the current land surface. And if you do that for every centimetre of the core, you get a rather detailed record. If you then manage date the core with good precision you have your sea level reconstruction!

This is what you would then see through your microscope. A salt marsh foraminifer is encircled.

We tend to look for salt marshes with a tide gauge nearby; these record sea level in real time. The oldest records go back hundreds of years; if our reconstructions match these records we have faith in them, and assume they also describe the period from before the start of the tide gauge record as reliable.

So after all that work, what are the questions we want to answer with this kind of research? There are many. One is, for instance, if we find accelerations in sea level rise of which the timing is consistent with the industrial revolution as a possible cause. Another one is how fast such accelerations in the past have been; it might be good to know how fast such processes can take place. Another one is if we can attribute specific sea level changes to specific ice caps; if so, we get some idea of what to look out for. If the West Antarctic Ice Sheet has collapsed in the past, and we can figure out how fast that went, we know what to get ready for. It may happen again! And how we can distinguish between the various ice caps (there are many other sources of sea level change, of course, but in the long run the ice caps are the biggest players) is material for another entry…

The author on a body of ice. Not an ice cap, admittedly.

iGlass

iGlass

“Don’t get bogged down in the marsh work!” Whether that was a witty comment or not I’ll leave to the readers, but it sure was the concluding remark of the iGlass kick-off meeting. Some may think iGlass is one of the newer Apple products; it seems there once was an April Fool’s day spoof claiming Apple had indeed produced some sort of cyber-glasses. And there's more of such to be found; no idea if they're real, but there seems to be an iGlasses app that distorts images, and there are iGlasses for the blind, with obstacle detection... But in this context it’s a big scientific project, funded by the Natural Environment Research Council (NERC), aiming at studying interglacial sea level.

So why is interglacial sea level worth so much of your tax money? We are currently living in an interglacial, sea levels are rising, and billions of people live pretty close to sea level. In order to not let the lives of countless many of these get disrupted we need to know how fast sea level can rise under circumstances like those of today. And where can one find information on such things? In past interglacials. Earth has experienced a switching between cold (glacial) and warm (interglacial) states for roughly a million years now; an interglacial occurs approximately once every 100.000 years. Sediments from these periods have survived, and they contain a wealth of information on the environment in these periods, available for those who are willing to interrogate them thoroughly. And that information will provide a good idea of how fast sea level can rise by how much in times like ours.

Policy makers need such input to base their adaptation policies on. If you know within what range sea level changes will be, you might know whether you can get by with strengthening your defences, or whether it’s time to start building wholly new ones. Or perhaps plan a retreat, if defence isn’t economically feasible.

So why the reference to marsh work? This project seeks its data in four fields: sea level information contained in dripstone cave sediments (speleothems), corals, Red Sea sediments, and tidal marsh microfossils. And yours truly is part of the team that will scour the lands for interglacial salt marsh sediments to which we can apply our usual method of sea-level reconstruction. What is that? Explaining that will take another blog entry. We have already found salt marsh sediments with micrfossils we can prod. That, too, is material for another blog post. The project will run for four years, three of which involve me; the stream of blog entries from this project will be considerable. Welcome to iGlass!