Aubert's analysis of phylogenetic terminology, part 2: definitions

Continuing the discussion of this paper from here. Originally I had the idea of going through the pages in sequence, but it may be more productive to tackle one by one what appear to be the main claims of the paper as I see them:

• The various definitions provided in the paper are in some way better than the ones that are currently accepted.

• There is no relevant difference between the systematics-relevant relationships and structures existing at any level of the diversity of life. (E.g. mother > daughter is completely equivalent to bony fish > land animals - they can all be drawn as diamonds and arrows, right?)

• A strictly phylogenetic classification is formally impossible.

• Cladism is part of structuralism and therefore characterised by "anti-realism and a metaphysical way of thinking".

• Cladism is built on biologically unrealistic assumptions that have been empirically falsified.

• There exists an objective approach to delimiting paraphyletic groups.

• It would be preferable to have two parallel classifications, one of clades and one that includes taxa that are allowed to be non-monophyletic.

So this might turn into seven separate posts, although the last few will perhaps be short. This is the first one, dealing with the definitions, and it got rather long.

Aubert's analysis of phylogenetic terminology, part 1: abstract

As always the following is my personal opinion and does not necessarily represent the opinion of any of my friends and relations, of my employer or colleagues, or of anybody whosoever except me.

I have recently set an alert with the key word evolutionary systematics (or similar), and today it delivered the first noteworthy catch: Damien Aubert, A formal analysis of phylogenetic terminology: Towards a reconsideration of the current paradigm in systematics. Published in Phytoneuron, an online journal that has peer review "if deemed appropriate or necessary by the editor, or if requested by the author", this piece of criticism of phylogenetic systematics runs over an astonishing 54 pages. It will certainly have to be tackled in homoeopathic doses.

So for the moment, let's just have a look at the abstract and table of contents.

Fun with trendline charts

Via Pharyngula I was recently lead to an American blog that had produced the following chart of average annual global temperatures, apparently in an attempt to demonstrate that we need not worry about the greenhouse effect:



This is just so totally awesome, I thought I would do a few myself. First, did you know we don't need to worry about overpopulation either?



Indeed there is absolutely no population growth at all! Next, watch my daughter grow up:



Finally, I tried my hand on one of those Kurzweilian charts of exponential technological progress:



Seems like we won't see a technological singularity any time soon. Checkmate, futurists!

Wildflowers of Mount Majura Nature Reserve

Living directly next to Mount Majura, we have over time built up quite a list of photos of the plants in the reserve. Perhaps this will be useful to other wildflower enthusiasts. It is obviously far from complete and heavily biased towards the groups we personally find attractive, like daisies and legumes. I may update the list in due course.

Asterisks indicate introduced species. Last updated 23 October 2016.

Ferns

Ophioglossum lusitanicum

Widely distributed across the globe and apparently not even rare in Australia, but easily overlooked because it is tiny and green. We had been visiting Mt Majura reserve for six years before we saw it the first time.

Cheilanthes sieberi

These ferns are unusually drought-resistant, rolling up their leaves to conserve water as they dry out. There is at least one other very similar species in the genus.

Australasian Systematic Botany Conference 2015, third day

On the third day I unfortunately had to miss several talks. The main topic of the day was Integrated Floras, Electronic Floras, and Online Keys.

In the morning session chaired by Zoe Knapp, Ilse Breitwieser's keynote lecture gave an overview over the various types of floras or flora-like publications, starting with her first use of the Schmeil-Fitschen field flora of Germany as a student. She explored the definition of a flora, of an integrated flora, and of an electronic flora - not just a digitised book but a flora curated and updated in an electronic data management system. She then covered a variety of 'learnings' from the eFlora of New Zealand including the problem of managing authorship rights and copyrights in an increasingly collaborative, dynamic and openly accessible workspace.

Australasian Systematic Botany Society Conference 2015, second day

Writing about the second day of the ASBS Conference 2015 I should first mention that I should now really be considered biased because I chaired the morning session and gave my own talk in the afternoon.

The day started with the session on Genomic Data in Plant Systematics. In his keynote Craig Moritz, the director of the ANU/CSIRO Centre for Biodiversity Analysis, set the scene by providing an overview of next generation molecular and analytic methodologies and their use cases. He also discussed the new possibilities arising in what he called a post-phylogenetic world - not in the sense of 'evolutionary' systematists of course, but in the sense of having achieved more or less complete taxonomic description and the availability of decent backbone phylogenies for at least some taxonomic groups. In particular, he mentioned the integration of population genetics and phylogenetics, the study of speciation mechanisms, and cryptic diversity.

Next, Todd McLay presented results form his research on species delimitation and phylogenetics of the grass tree genus Xanthorrhoea. I was particularly intrigued by a new PCR based reduced representation library preparation method that he developed, because it seemed to be comparatively simple and thus perhaps feasible even in shorter student projects. Benjamin Anderson then gave a very concise talk on this work in the arid zone grass Triodia.

Australasian Systematic Botany Society Conference 2015, day one

This week our herbarium is hosting the annual Australasian Systematic Botany Society Conference. For me this is the first time to be involved in conference organisation, specifically the scientific program (deciding on conference theme and major sessions, inviting keynote speakers, organising workshops, deciding on abstract acceptance, grouping talks into sessions, etc.).

Yesterday started with a long session on collections science chaired by Sarah Mathews. Keynote speaker Vicki Funk of the Smithsonian stressed the importance of natural history collections in the genomic age and identified three game changers for the near future of collections science: open access to data and images, improved sequencing of degraded DNA from old specimens, and linking collection specimens with phylogenies and climate data. I was also amused by an anecdote she told of discussing phylogenetic systematics with an older, very influential traditional taxonomist who argued that not being allowed to recognise taxa based on plesiomorphies amounted to "throwing half my data away". Vicki then tried to explain that the data are used, only deeper in the tree, where those character states were apomorphies themselves. The amusing aspect is of course that 'evolutionary' taxonomists still haven't grasped that a generation later.

The collection science session continued with a talk by Jill Brown on crowd sourcing of data entry at the herbarium of the University of Melbourne. They are involving volunteers through the ALA DigiVol portal, and the project appears to be quite successful. Liqin Wu then presented an analysis of environmental lead accumulation in historical lichen specimens, an interesting use case of collections. She also identified possible lead sources (soil/rock, leaded petrol, coal burning) based on isotope ratios.

Botany picture #220: Santolina chamaecyparissias

Just now flowering in our courtyard: Santolina chamaecyparissias (Asteraceae), in English known as cotton lavender although it is neither a cotton (Malvaceae) nor a lavender (Lamiaceae). A nice little shrub with extremely aromatic leaves:

It is said that the dried leaves can be used for potpourri and little bags to place between the clothes.

Do half the natural history specimens in the world really have the wrong name?

On Friday a colleague drew everybody's attention to a recently published study from Edinburgh and Oxford: Goodwin et al. 2015, Widespread mistaken identity in tropical plant collections, is presented in press releases and media as demonstrating that, to quote the University of Oxford's news page, "half the world's natural history specimens may have the wrong name".

As museum and herbarium specimens are used to extract DNA for phylogenetic and evolutionary studies, to draw distribution maps, to inform conservation decisions, and to examine spatial patterns of diversity, this sounds pretty dire. Luckily, in my eyes at least, this interpretation is totally over-hyped.

(Full disclosure: I know one of the authors of the relevant study, as he was involved in selecting my Diplom thesis topic and allowed me to join a field trip he had organised.)

My first reaction to reading the sensationalist headline was that perhaps they are talking about insects, which account for the vast majority of natural history specimens. That would have sounded at least remotely plausible given how difficult insect identification is and how few entomologists there are. It turned out, however, that the study was dealing with plant (herbarium) specimens.

My next thought was simply, no way; just looking at the herbarium I am working at the situation is nowhere close to that bad. 5% perhaps, okay. So how do they arrive at these seemingly shocking numbers?

The problems I have with the way these results are discussed fall into three categories: selection of example cases, hasty over-generalisation, and equivocation on the term "wrong".

Conferences, pottery and botany picture #219: Actinobole condensatum

Yesterday morning I had the pleasure of presenting a talk on the daisy family Asteraceae to the Biennial Conference of the Australian Native Plant Society Australia* (ANPSA). It was the first time I have been at a conference that wasn't either political or scientific, and I found it interesting how it compares to our scientific society meetings such as the upcoming annual conference of the Australasian Systematic Botany Society (ASBS), which will also take place here in Canberra.

At the ASBS, we will have around 50 speakers over three days, nearly all of them out of their own initiative, and nearly all of them will have only 15 min. At the ANPSA, they have 21 speakers over five days, many talks appear to be invited, and speakers are alloted 45-60 min.

At the ASBS, we will have one field trip on the day after the conference. At the ANPSA, they have several field trips (excursions) every day throughout the week, although admittedly they do not go as far away.

Clearly priorities are slightly different - native plant enthusiasts can hardly be expected to get together every two years and not prioritise looking at native plants.

Anyway, at least one of the members must be into ceramics and pottery. Each invited speaker was given a little customised vase; at least two of us (including me) did not even remember that the society contact asked us months ago what our favourite plant was. It is hard to pick just one, but I now dimly recall that I nominated Actinobole condensatum, because this is what the artist, known to me only as Franzi from her signature on the vase, did:

And here, for comparison, a picture of Actinobole condensatum I took during a field trip to Western Australia in 2012:

It is a great impression and abstraction, getting across a good likeness of the species. And the species is really a super-cute desert ephemeral. The plants are very tiny and short-lived, but they produce a dense, attractive cluster of small but typical paper daisy heads. The red sand on which they like to grow does its part to make for an aesthetic impression.

Footnote

*) Yes, that extra Australia seems a bit odd at first sight, but I understand that it is meant to differentiate the national society from the local chapters, as in Australian Native Plant Society Canberra Region, and not from a hypothetical Australian Native Plant Society Botswana.

Botany picture #218: Clitoria

Sigh. Just too tired these evenings to write anything, and then Paris... so just another nice plant for the moment: A Clitoria (Fabaceae) from eastern Bolivia, 2007. Don't know the species name unfortunately, but it should be clear where the genus name got its inspiration. And yes, it is the right way up, the flowers of this genus are generally resupinate.

The historicity of Jesus

One topic that regularly comes up in parts of the blogosphere I read is whether there was a real human being at the root of the Jesus character of the Bible or whether, alternatively, such a person never existed. What the alternative looks like in detail is a bit unclear and depends on who is arguing; one of the favourites seems to be the idea of Jesus as originally a divine being in some other realm. Then the gospels were written as allegorical teaching material or fantasy novels, and a few generations later all Christians had weirdly forgotten that those were only novels and became wrongly convinced that Jesus had actually walked the earth.

Both those who argue for an entirely mythical Jesus and those who see a real life human doomsday cult leader at the root of Christianity make their cases with a lot of conviction, in fact with so much certainty that one would usually assume they must be really sure that they got it figured out. Unfortunately, again, both sides do so, and I am clearly not qualified to evaluate the Ancient Greek source material and suchlike.

For what it is worth, I lean towards the assumption that there was a human cult leader named Jesus (I understand it would then have been something like Yoshua?) at the root of Christianity, obviously in my personal opinion without any actual virgin birth, divinity, resurrection or other miracles involved. My main problem with the mythicist position is that it seems really hard to explain the content of the gospels under their hypothesis. Just to pick the three first items that pop into my mind, and of course none of these thoughts are original to me:

Botany picture #217: Xerochrysum viscosum

The official golden everlasting, likely the economically most important ornamental daisy native to Australia, is Xerochrysum bracteatum. Here around Canberra, however, we have its congener X. viscosum, which has narrower, slightly sticky leaves.

Although X. bracteatum gets all the attention, I have always thought that X. viscosum is equally pretty, and of course if you want a paper daisy in your garden in Canberra it would probably be the better choice because it is well adapted to the local soil and climate.

What is missing are, of course, all the strange colour variants that X. bracteatum has been bred into. Xerochrysum viscosum is pretty much yellow, that's it. Or is it?

What prompted me to choose this species for the present post was that today, during our morning walk, we happened upon the above orange form. It was just one plant among hundreds of yellows, but certainly this kind of occasional sport must have been the basis for the breeding that was done in its better known relative. So there is potential; who know what other colour forms may crop up here and there?

Reading Stormfront, Book One of the Dresden Files

The last three weeks have been a bit full; first field work, then meeting, then moving house, and then a bad cold. But although we are still sitting between boxes waiting to be unpacked, I finally feel like writing something again.

At the last Lifeline book fair I bought a couple of books. Let's start with the first I read, Jim Butcher's Stormfront - Book One of the Dresden Files. Minor spoilers obviously ahead.

Field work in southern Queensland, part 3: Barakula State Forest

The area north to us, and in particular Barakula State Forest, seems to have received more rain than the drought-stricken areas we visited in the first two days. Grasses are greener, more flowers were out, and we were considerably more successful in finding the species we were after.

Typical view in Barakula State Forest: seemingly never-ending straight roads.

Brunonia australis (Goodeniaceae); I had previously seen it near Alice Springs in the arid zone and was consequently a bit surprised that it grows here in a forest.

This epiphytic orchid was only in reach of my camera because the tree it grows on had fallen over. Cymbidium canaliculatum (Orchidaceae), as far as the photograph allows identification.

As mentioned in the previous post, the cactus moth that killed off most of the Opuntia infestations is understandably a big thing in this area. We drove past a memorial hall dedicated to this species of insect.

Field work in southern Queensland, part 2: Interesting invasives

Australia surely has its fair share of introduced weeds and invasive plants. On this trip I have already seen a few that I had only heard of but not seen before, and others that are much more abundant here than further south.

Opuntia is one of the textbook cases of an economically promising plant turned into horrible invasive weed but also of biological control done well. I remember even as a teenager seeing a documentary that showed first near-monocultures of Opuntia cacti covering the Australian landscape and then the devastation the biological control agent - a moth - caused in the populations of the cactus after it was released. There are memorials in this area celebrating the defeat of the cactus and the efforts of the moth. Wikipedia has a nice little entry on the issue.

Above the flower of a low-growing specimen. Apparently numerous species of the genus had been introduced, so I am not sure which one this is.

One of the plants I had read about but not seen before is Hypochaeris microcephala (Asteraceae), one of several weedy species of its genus introduced to Australia, but the only white-flowered one.

Finally, a Bryophyllum (Crassulaceae). We saw it frequently along roadsides, but most of the plants were past flowering and presented merely shrivelled, blackish stems. I assume this species was introduced deliberately as an ornamental.

Field work in southern Queensland part 1: Mistletoe mania

Currently doing field work in southern Queensland. We are primarily trying to find a certain rare species, but today we were not yet lucky. Part of the problem may be that the area is quite dry at the moment, but then again lots of other plants are out and in bloom, so maybe that is not the main issue. Particularly amazing was to me how many different species of mistletoes we have seen in a single day. Unfortunately I do not know any of the names yet, but some of them are quite pretty, especially considering the unspectacular Viscum album we had in Germany.

This one parasitised on an Acacia...

...as did this green-flowered one here.

Certainly the most stunning species we found first on a Eucalyptus, but it did not seem to be very host-specific.

Finally, a single Allocasuarina tree had two species of mistletoes on it, of which I only show the weird leafless one. The other was similar to the first picture but with smaller flowers and long, slender leaves.

Botany picture #216: Astrotricha longifolia

Currently proposal writing, travel preparations and having to move to a new apartment conspire against any decent blogging. Therefore another picture from our New England trip, Astrotricha longifolia (Araliaceae). The name means long-leaved star-hair.

A fast alert or a slow editor?

Okay, that is a first. My co-author and I just learned that we got a paper accepted not from a message from the editor but from my Google Scholar Alert on the topic we are working on. Apparently the journal published the abstract as "just accepted" on its website before even telling us that the manuscript was accepted. Weird.

Botany picture #215: Lemna disperma

No time to write something substantial, so here is another plant seen on our recent holiday trip. I have long found floating plants fascinating; and one of the most interesting aspects is how quickly and drastically their morphology changes compared to their closest relatives. In the case of duckweed like the above species, they are part of the Araceae family and thus represent perhaps the most extreme example of massive reduction in size and complexity found in all the flowering plants.

The species in this case is Lemna disperma. Or at least that is what the Flora of New South Wales suggests, I have not actually checked against a world wide key to the species of Lemna. The genus, however, is easily recognised. There are five genera of duckweeds, and simplifying a bit the really tiny rootless specks are Wolffia, rootless but larger and longish, often boomerang-shaped ones are Wolffiella, those with only one root per thallus are Lemna, and those with multiple roots are Landoldtia and Spirodela.

For those interested in more about the bizarre world of duckweeds, there is a tremendously detailed website available, although of course it has a bit of a focus on the country of its author.

New England holiday trip, third and final part

We are back now, so this post will cover the rest of our trip in one go.

Another nice waterfall, the Dangar falls north of Dorrigo. Later we passed two more little waterfalls, Sherrard and Newell Falls, but they were directly on the Dorrigo-Bellingen road and thus not easy to photograph.

A theme of this last part of our trip was giant tree tourism. Above is the Giant Tallowood (Eucalyptus microcorys) east of Megan. A sign announced that it had a diametre of 3.14 m and a height of 56.5 m. I do not know what the virtues of its wood are, but the locals appear to consider the species to be very significant, as one can see a Tallowood Cafe and suchlike.

After spending a night in pleasant little Bellingen - the most hippie town I have ever seen in Australia - we were essentially on our way back. We left the New England area even in the loosest sense and drove south along the coast. But before driving through in a dedicated manner we spent some time in the vicinity of Laurieton. This is another town that I can only recommend - our motel, the Indian restaurant in the centre, and the surrounding landscape were all extremely enjoyable.

As for that landscape, the area has three forested hills that are so similar that they were named the Three Brothers. The above picture shows Laurieton as seen from the North Brother in Dooragan National Park.

The rainforest on the southern slopes of the North Brother was amazing. I would not have thought to find strangler figs and well-developed Brettwurzeln (buttress roots) so far south of the tropics. There were massive tree ferns and slender palms, epiphytic ferns we had not seen before, and trees with wonderfully soft, corky bark. The picture here shows another very odd plant: Gymnostachys anceps. Although its overall habit immediately suggests a sedge, it is of the arum family Araceae.

To give more of an idea of the overall landscape, this is a view from Donbogan Lookout in Kattang Nature Reserve, with the base of the North Brother just reaching into the picture from the right.

In Middle Brother National Park we then continued our giant tree tourism. Shown here is the Bird Tree, considered to be the largest tree in New South Wales by volume. Unfortunately there was no sign providing its measurements or species name...

...but it is surely an impressive specimen! Interestingly, there were quite a few other visitors, whereas the Giant Tallowood did not have any apart from us. Then again, that was during the week, and we saw the Bird Tree on a long weekend, so who knows.

New England holiday trip, part 2

We were without internet access for a few days, so this post is a bit behind the time; it covers Tuesday and Wednesday. We made our way eastwards of Armidale along the aptly named Waterfall Way and spent two nights at Thungutti Campground in New England National Park. Problem was, it is reasonably close to the peak of Point Lookout, a mountain of more than 1,500 m, so the nights were cold!

Anyway, there were indeed lots of waterfalls and nice lookouts.

The first picture shows Gara Gorge as seen from the eponymous lookout. This is still near Armidale and fairly dry at the moment.

Here shown are the Wollomombi Falls in Oxley Wild Rivers National Park and the smaller Chandlers Falls to the right above them. Wollomombi Falls are considered to be the second tallest waterfall in Australia.

The other waterfall in this post is the Upper Ebor Falls in Guy Fawkes National Park. As the name implies there is a lower step further down; it seems taller but less photogenic.

Back to forested slopes: A view from the summit area of Point Lookout. We were lucky with the timing, as some time later it got cloudy.

Finally, something botanical: Lophozonia moorei (= Nothofagus moorei, Nothofagaceae). This is the first southern beech I have seen that has large leaves like the northern beeches of the genus Fagus. The southern beeches I have encountered before - in Patagonia, Tasmania and New Zealand - all had very small leaves.

By the way, I still don't really understand why Nothofagaceae can't just be Nothofagus, and why Nothofagaceae can't be in Fagaceae given their close similarity to Fagus. (I assume the two families do form a clade?) I guess I am a lumper at the genus level.

New England holiday trip, part 1

We are making use of school holidays to go on a little trip to Australia's New England area, i.e. the north-east of New South Wales. This is the first time we visit it. We have been making our way there slowly over Saturday and Sunday, and on Sunday evening we were generously welcomed to Armidale by botany professor Jeremy Bruhl, his family, and fellow botanist Ian Telford. We will explore waterfalls, forests and lookouts of the New England high country over the next few days.

The above is the view from Moonbi Lookout back towards Tamworth, the last really large town we passed through before reaching Armidale (it is too far away to be visible though).

Today I dropped into the N.C.W. Beadle Herbarium of the University of New England, of which herbarium Jeremy Bruhl is the director. Read more about this scientific collection, its importance and history on its website.

An impressively floriferous and sweetly smelling shrub we saw on the way near Premer is this Santalaceae. I am reasonably sure it is Choretrum candollei.

The Templeton Test in parsimony analysis: part 2, how to do it in PAUP and TNT

After discussing the Templeton Test in an earlier post, this post is about how to conduct it in practice.

Floriade 2015

Impressions from our visit to the Floriade spring festival yesterday.

Tulip mania! Interestingly, the red ones were still behind the white and yellow ones, meaning that the plantings will only really come into their own in a week or so.

With the first World War a hundred years ago, Australia has had war related events since last year and is set to continue until 2018. As a German I find it fascinating to see the difference in perspective, as in Europe the horrors of WW2 have totally overshadowed anything that happened in the first, which is also much further back in the past. But Australia lost such a large number of young men that WW1 left a more lasting impression than it did in much of Europe.

Anyway, poppies are apparently associated with remembrance of war. Here people could pay a bit of money for a poppy to place on the wall, and the proceeds went to a charity.

The view from above - this is the first time I was on the Floriade's Ferris Wheel.

Lifeline Book Fair

Great haul at the LifeLine Book Fair this spring, it was a good idea to go early on Saturday this time.

The Templeton Test in parsimony analysis: part 1, principles

When we want to know whether a taxon, for example a genus, is monophyletic (and thus acceptable in a phylogenetic classification), the first thing to do is to infer a phylogeny. We may then find a topology like the following:

Genus A is non-monophyletic on this tree because B is sister to A2. However, the support value for clade A2 + B (the red number, 63 of 100) is not exactly stunning; if this is Bayesian Posterior Probability, you would want 95 or higher, and if it is bootstrap or jackknife you would still want to see at least 80 or so, preferably more. With so little support it could just as well be that these relationships are wrong and genus A is monophyletic after all.

(It is amazing, by the way, how many people find it hard to intuit that when discussing the status of A the red support value is indeed the relevant one. If it is high then precisely that number provides support for the non-monophyly of A while the black value is irrelevant - it merely shows that A1, A2 and B belong together but doesn't tell us anything about A versus B. Some time ago I even had a peer reviewer who got that wrong at first. Perhaps people are just so trained to look for how strong the evidence for monophyly is that they can get confused when they need to look for evidence for non-monophyly.)

So yes, the tree shows A as non-monophyletic, but we can't be sure if the evidence is strong enough. Is there another way of testing whether, let us say, A is "significantly" non-monophyletic?

This is where, for parsimony analysis, the Templeton Test comes in, which by the way doesn't have anything to do with the Templeton Foundation.

Botany picture #214: Grevillea arenaria

Grevillea arenaria (Proteaceae) is described in the online flora of New South Wales as "red, pink or orange, often green or yellow at base", but if the label on this specimen in the Australian National Botanic Gardens is correct then it is surely quite on the green side. Perhaps a variant? Certainly the most unusual flower colour I have seen in this genus so far.

Isaac Asimov's Foundation

I spent much of the week at a meeting in Tasmania. On the last day I had time to browse a book store and finally bought the first Foundation novel after I had only found sequels and prequels at the local book fair so far.

It is not so much a novel as a compendium of several shorter stories, each with their own characters and representing several stages of the development of the eponymous Foundation. I have written before about some of the other books in the series (Foundation and Empire, Foundation's Edge). Although my observations on this book are similar to those on the later ones, somehow it doesn't feel quite as blatant.

Botany picture #213: leafy liverwort sporophyte

Recently went through a couple of old pictures and found this very lucky photograph. It is already a bit lucky to find liverwort sporophytes because in contrast to those of mosses and hornworts they are very soft-bodied and short-lived. And then I was lucky enough to get quite a decent snapshot despite limited light in the understorey and the notorious problems my camera has with focusing on thin objects.

I do not know the species or even the genus, but it is a leafy liverwort growing on a log in a southern New South Wales national park in 2012, and it shows some of the typical traits of a liverwort sporophyte: soft stalk, sporangium (~capsule) opening with four valves, and the longish elaters in the sporangium that help disperse the spores with their hygroscopic movement.