Monthly Archives: March 2015

Reviewed: The Incredible Unlikeliness of Being; Grandmother Fish

In an earlier post, I said that the right way to undermine creationism is to promote appreciation of the science of evolution, by presenting it in ways that are engaging, enjoyable, and above all personal. In this post, I review two more books that succeed in doing this; Alice Roberts The Incredible Unlikeliness of Being and Jonathan Tweet‘s Grandmother Fish.

UnnamedGrandmother Fish is a book like no other I have seen. It is an introduction to evolution, for adults to read to their pre-school children. It is also much more than that, and comes with well-earned commendations from Stephen Pinker, David Sloan Wilson, and Daniel Dennett.

We start with a delightfully drawn Grandmother Fish, who lived a long, long, long, long, long time ago and could wiggle and swim fast and had jaws to chomp with. At once, this is made personally relevant: “Can you wiggle? … Can you chomp?” We proceed by way of Grandmother Reptile, Grandmother Mammal and Grandmother Ape, to Grandmother Human, who lived a long time ago, could walk on two feet and talk and tell stories, and whose many different grandchildren

could wiggle and chomp and crawl and breathe and squeak and cuddle and grab and hoot and walk and talk, and I see one of them … right here!

Each stage has its own little phylogenetic tree, with the various descendants of each successive “grandmother” shown as each other’s cousins, and there is an overall tree, covering all living things, that anyone (of any age) will find interesting to browse on. Finally, after some 20 pages of simple text and lavish illustration, there are around 4 pages of more detailed information, directed at the adult reading the book, but to which I expect children to return, as they mature, remembering the book with affection, as they surely will, years or even decades later.

So here we have nested families, family resemblance, and the development of more and more specific and complex features. And any adult, or indeed any alert child, will readily extend the discussion. Was there a grandmother cat, whose grandchildren include lions and tigers and pussy-cats, and how was she related to grandmother carnivore? Where do fossils fit in? (The tree shown includes pterodactyls, dinosaurs, and early birds.) And the most common arguments against evolution, from “only a theory” to “where are the intermediate forms?” to “if evolution is true, why are there still monkeys?” will stand immediately revealed as the nonsense they are. Indeed, one of the few statements in the endnotes that I disagree with is that “Evolution by natural selection is very difficult to understand because it doesn’t make intuitive sense.” It will, in my opinion, make perfect sense to a child who has met so clear an exposition early on, and who will therefore find it much easier to understand intuitively than, say, Noah’s Ark.

Back story: this project was crowdfunded on FaceBook, on the basis of some initial sketches and text. The author professes a long-standing interest in evolution, but his career hitherto has been elsewhere, in computer games (he was lead designer on the 3rd edition of Dungeons and Dragons). However, he has had expert advice from many people, including Eric Meikle, Education Director at the [US] National Center for Science Education.

Publication: pending. Initial partial draft available on request here (technical note: the mammalian tree shown there has since been updated). Diagram from book draft website.

Disclosure: I have corresponded with the author who tells me I will be thanked on the book’s website. Review based on initial draft + correspondence with author. I will be buying this book for my grandchildren as soon as it becomes available.

Alice Roberts The Incredible Unlikeliness of Being, despite (because of?) coming from an established author and presenter, is as personal as could be. It starts with Alice Roberts’ emotional response to becoming a mother, and the incredibly unlikely being is the reader. The subject matter is (mainly) the development of the human embryo, and that developing embryo is not some third party abstraction, but you. And so evolution is also about you, as example after example throughout the book makes clear:

It’s about your evolutionary heritage, and it is about your own embryological development, when you grew in changed, part of you folding like origami, until you are shaped like a human.… This is the best creation story, because it is true.… This scientific story, pierced together from many different sources of evidence, is more extraordinary, more bizarre, more beautiful, than any creation myth we could have dreamt up.

Alice Roberts is Professor of Public Engagement in Science at the University of Birmingham, and one of the new generation of writers and TV presenters who in the UK fill much the same role as Bill Nye and Neil deGrassie Tyson in the US. She is by training a doctor and anatomist, and much of her own research has involved forensic examination of pre-human hominin skeletons, the coldest of “cold cases”. This background shows up clearly in her detailed descriptions of your developing structures, and she shares with us her emotions about coming face-to-face (in one case literally) with her own anatomy, as when, after x-ray tomography, she was given a replica of her own skull.

My Day on a Plate

Prof Alice Roberts holding a replica of a skull (not, in this case, her own)

The unlikeliness is not just the obvious unlikeliness of your two particular parents meeting, of that one egg becoming fertilised, and of that one sperm out of the enormous number available on being successful. Nor even of the improbability of your parents in turn having come into existence, and so on. Behind all this, and multiplying all those improbabilities, is the meandering history of our evolution:

The more I delve into the structure and workings of the human body, the more I realise what a cobbled-together hodge-podge of bits and pieces this thing we inhabit really is. It is brilliant, but it is also flawed. Our evolutionary history is woven into our embryological development and even adult anatomy in surprising ways; many of our body’s flaws can only understood in an evolutionary context.

We start with a history of ideas, and here it struck me as remarkable how long it took for it to be generally recognised that both parents contribute to the form of their offspring, despite the obvious evidence from physical resemblances. Leeuwenhoek with his microscope first observing sperm, the much later discovery of the mammalian ovum, a comical (in hindsight) controversy between “spermists” and “ovists”, the puzzle, insoluble even in principle until the advent of genetics, of how both parents could contribute to what we now call the information content of their offspring, and the further conundrum, unsolved until DNA was identified as the genetic material, of the material means by which they did so.

Most of the book is concerned with the complex process that leads from first release of the ovum, through fertilisation, implantation, and the many subsequent stages of development, through to birth. This story is inextricably intertwined with the story of your evolution, and I can only pick out a few of the most salient points from a wealth of fascinating detail.

From cell division to implantation, with the cells beginning to form separate layers

There are, of course, vestigial or discarded organs. In your second week of development, when you were not much more than a couple of layers of cells, you generated a yolk sac, homologous with the yolk sac of fish, amphibians, reptiles, and even those mammals (the platypus and the spiny anteater) that lay eggs. The difference is that in these the yolk sac is filled with the nourishment that will sustain the growing animal until its birth, whereas in placental mammals like us, it has been without function for the past 90 million years or so. Nonetheless, the recipe for making it has never been deleted from your assembly instructions.

At an early stage, it is very difficult to distinguish the embryo of a mammal (that includes you, of course) from that of a fish; a little later it is still difficult to distinguish it from a reptile or a bird, and different mammalian embryos continue to resemble each other for even longer. For a while, it was suggested that this is because you were retracing your evolutionary history, but we now know that this idea is based on a mistaken model of evolution. You are not more highly evolved, than, say, a chicken; you have just evolved in a different direction. The earliest stages of development are shared with fish, later stages with reptiles and birds, and later stages yet only with mammals and eventually only with our fellow apes. Thus we do not, strictly speaking, recapitulate our evolution from a fish, nor should we, since the present-day fish is as remote as you are from your last common ancestor with a halibut, but we do recapitulate shared development until the parting of the ways. The new science of “evo-devo” is now beginning to take this story down to the most fundamental level, identifying the molecular basis for the parts of the construction plan that you share with a fish, and the parts, activated later, that you do not.

The cartilage base of human skull resembles that of other mammals.  It is only later, when this is being transformed to bone, that it acquires its specifically human form, with the enlarged dome required to house the brain towering above the rest of the head.

Working down from the head takes us to the larynx, and the unanswered question of the origin of human speech. Here the problem is that the really important working parts – the larynx itself, its associated muscles, and, above all, the tongue – are soft tissues and leave no trace in the fossil record. The position of the larynx lower in the throat, compared with other mammals, may be no more than an accidental consequence of the way our oversized brainboxes sit on top of our spinal column.

The origin of the larynx leads us to the most striking embryological evidence for evolution, namely the direct resemblance between the branchial (gill) bars of fish, and the related structures found, early in development, in terrestrial vertebrates. Then comparative embryology allows us to map our own organs against their fishy counterparts, and to explain some of the more absurd features of our own anatomy.

Our fishy origins are clearest early in development. By week four, the bundle of cells on its way to becoming you has separated into three separate layers, a tube within a tube within a tube. On the outside, ectoderm, which will give rise to your skin; on the inside, endoderm, which will give rise to your digestive tract, from one end to the other, and in between mesoderm, giving rise to a variety of structures. By week five, we can see what will become the backbone, the eye, and the branchial bars in the neck. Each branchial bar has ectoderm on the outside, endoderm inside, and in between a mixture of cells, some from mesoderm and some from neural crest. This in-between layer will develop into a cartilage bar and muscles, and each bar will develop an artery and a nerve.

Land animals and fish have shared much the same developmental instruction manual until this point, but now they begin to diverge. In fish, the branchial arteries accept blood directly from the heart, and the cartilage forms the gill arches. In land animals, development is far more complex. One set of gill muscles becomes larynx muscles, and a nerve that leads to it runs down into the chest, before making its way back up to the top of the throat. Why so? Because the blood vessels that, in fish, run directly between the heart and the gills have become, in land animals, the aorta and main arteries leading from it. And as a consequence, the recurrent laryngeal nerve, as it is called, is trapped beneath the aortic arch when the heart moves downwards, as it does in land animals but not in fishes, and forced to take this convoluted path. Bad design, but an unavoidable consequence of evolutionary history. A creationist with whom I once discussed this suggested that this really was a good design, because it protects the nerve from damage. Tell that to a giraffe.

The first branchial arch gives rise to bones that are part of the jaw joint in reptiles, but in mammals have shifted and shrunk and become two of the bones of the inner ear. And yes, there is an intermediate form, an early mammal with two jaw joints, the outer one thus being made free to move closer to the ear to improve resonance, and, ultimately, to detach itself. Gill flap muscles in the fish end up as face muscles in primates including us, and so on. The cleft between the first and second branchial arch gives rise, in us, to our ears, and to the tubes that connect the middle ear to the throat, thus enabling pressure to equalise.

Descending to the molecular level, these developments are orchestrated by a set of control genes, prominent among them the so-called “homeobox” or Hoxgenes, first discovered in fruit flies, where they regulate the formation of the segments of head, thorax, and abdomen. Similar genes are found in every segmented animal, including us (if you don’t think you’re segmented, think of your backbone and ribs). This arrangement must be very ancient, since your last common ancestor with a fruit fly was some 800,000,000 years ago, but has undergone elaboration. The fruitfly has 8 Hox genes, lined up in a row, that come into play one after the other. In the lancelet, this has been expanded to 14. At some stage between the lancelet and jawed fishes, the entire genome seems to have doubled and redoubled, so that you have four sets of Hox genes, each on a different chromosome.

Some aspects of this regulatory system are much more flexible than others. All land vertebrates have a spine with the same basic sections: neck, chest, lower back, sacrum, and tail. All mammals have just seven neck vertebrae, whereas the number of tail vertebrae is highly variable, being up to 49 in one species of porpoise, which flexes its tail to swim, while our tail, or coccyx, has only 3 to 5 fused together. This tail can be considered as a vestigial organ, since it is a mere relic of that sported by our monkey-like ancestors, but like many so-called vestigial organs it continues to earn its keep, in this case by acting as an anchor for muscles. Our lower backs have one more vertebra then our chimp cousins, and are less securely held in place, developments thought to be related to our habitual walking on two feet

Relevant to Professor Roberts’ own anatomical interests, although less directly so to the question of embryological development, is the detailed history of our limbs. This indicates us to have been truly bipedal as long ago as 3.2 million years ago (Lucy), while long legs at 1.5 million years ago (Narikotome boy) suggest adaptation for running. In popular imagination, we learned to stand upright as we evolved away from knuckle-walking ancestors, but the reverse may be the case. Monkeys, like us, have feet far harder and less flexible than those of modern non-human apes, and Prof Roberts speculates that our ancestors were tree walkers. If so, it is the apes, with their prehensile toes, rather than us, who have diverged from the form of our common ancestor.

But once we started walking on the ground, that change in behaviour, which could occur within a group in a single generation, would have suddenly generated a new set of selection pressures in favour of long distance walking and running. This is an activity for which we are superbly adapted, even though only a few groups, such as the Tarahumara in Mexico, still regularly practice it.

The final Chapter reviews our present understanding, and considers our place in nature.  Development is controlled, more or less, by DNA, including control genes as well as directly expressed genes. It is not, as Haeckel thought, a true recapitulation, but shows clear echoes of earlier stages – segments, gills, fish hearts, the lancelet brain. Our developmental biology is, to use one of Prof Roberts’ many memorable metaphors, a palimpsest.

Similar environmental pressures can give rise to similar adaptations, so that the mammalian ear with its three tiny bones has evolved at least four times in different lineages, while, as hinted above, different ways of moving around including bipedalism may have arisen more than once among our ancestors and their close cousins. But nonetheless, evolution remains unpredictable, if only because changes in the environment are unpredictable. One such change was that triggered by the asteroid that did for the (non-avian) dinosaurs. Selection acts without foresight, and without that asteroid, we would not have had humans (for what it’s worth, my own view is that we would have had the intelligent descendants of the velociraptors instead).

Evolution takes place in context, and that context, for a species capable of learning from each other, includes a technology. An innovation in toolmaking could have spread through a group of our ancestors in a single generation, triggering a new set of selection pressures that moulded their hands and bodies to a new set of tasks. We speak of the survival of the fittest, but fitness here refers to the cultural, as well as the natural, environment. And we are more influenced in our lives, and our evolution, by our own culture and its artefacts than any other species.

The book concludes with reflections on our similarities (profound) and differences (striking, yet perhaps more quantitative than qualitative) from other species, our contingent and transitory nature, and our uniqueness both as species and, returning to the starting point, individuals.

There are numerous drawings (Prof Roberts is an award-winning artist), and an extensive bibliography.

A few detailed comments. Prof Roberts shows, early on, a series of drawings copied from Haeckel. Connoisseurs of creationism will recognise this as a deliberate provocation, since creationist writers repeatedly point to alleged shortcomings in these, as reason to ignore the whole of developmental science. Lancelets are shown as sister group to vertebrates; in fact, we are closer to tunicates (the subphylum that includes sea squirts) than we are to lancelets, although tunicates only acquired their sessile habit after we and they had gone our separate ways (Prof Roberts tells me that this will be corrected in later editions. I occasionally found the layout of diagrams and their explanations rather awkward. This may be an inherent limitation of the e-book format that I was using.

Figures from Prof Roberts’ personal website, and Amazon website.

Disclosure: this review is of the first Kindle edition, personal purchase.

These reviews first appeared here, on 3 Quarks Daily

Trillions of Stone Age Artifacts: A Young Earth Anthropology Paradox

If there really were lots of people, not just Noah’s family, and they really were spread out over Africa, and if they really were making tools from some 2.6 million years before present, and if they were profligate throwaways when it came to flint flakes, then a little arithmetic shows that there ought to be trillions (yes, millions of millions) of discarded tool bits all over Africa. And there are.

Earlier, I blogged about time as interval at Siccar Point, and time as process where the lavas of the Giants Causeway were weathered between outflows. Now (see below, reblogged from Naturalis Historia) I can add time as the accumulation of junk. Time shallow by geological standards, but very deep indeed compared with all of human history, or with the imaginings of the author(s) of Genesis. And I don’t think even Ken Ham can talk his way out of this one.

And this week sees the resolution of another paradox: the oldest tools known date to some 2.6 million years before present (Mybp), but the oldest clearly hominin remains were at 2.4 Mybp. So do we have to infer that australopithecines made tools? Not necessarily, since (see here, and references therein) we now have a decidedly hominin-looking jaw at 2.8 Mybp.

There may be other implications for our ancestry. Jaw bones are the best preserved of all skeletal remains, but on their own they tell us little about what most interests us – the size of the brain case. However, where one fragment was found there may be others, and we can only await further developments.

Naturalis Historia

Trillions of stone artifacts cover the surface of the African continent. The product of the manufacturing of stone tools by hunters and gathers over long periods of time, these stone artifacts literally carpet the ground in some places in Egypt and Libya.

Just how much Stone-Age produced rock is strewn across the African continent?

Imagine a volume of rock equivalent to 42-84 million Great Pyramids of Giza.

The “million” isn’t a typo. That number sounds absolutely fantastic, doesn’t it?  Let’s take a look at how these numbers were derived.

The results of a study just published (see references below) shows how incredibly dense stone artifacts can be in some places in Africa.   Working in a remote location in southern Libya, researchers took surveys from hundreds of one or two-meter square plots. From the tens of thousands of artifacts found in them, they estimated a minimum density of 250,000 stone artifacts…

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A fracking lie. No more no less

By my geologist friend Michael Roberts.

I don’t like it when creationists tell lies and I don’t like it when anti-frackers tell lies, either.

My own view, for what it’s worth, is that the Royal Society probably know what they’re talking about when recommending that the UK proceed, but with tighter regulation than that currently at force in the US; that if more methane means less coal that’s a good thing (coal has twice the carbon footprint per unit of energy, as well as a whole shopping list of other disadvantages); that knee-jerk rejection of fracking is the very opposite of evidence-based decision making; and that quantified evidence-based decision making is crucial if we are to keep the lights on while keeping the climate change already in process within tolerable bounds. June 2012 Jan 2015 and references therein

Peddling and Scaling God and Darwin

Here’s the latest picture doing the rounds to show earthquake damage done by fracking


Or more clearly ;


Now this looks very scary  and will make people concerned that will cause quakes in their area. However twitter sleuth aka sadbutmadlad took on the roll of Sherlock Holmes and soon found that this terrible shot had nothing to do with fracking and was in fact caused by a 7.5 quake near Yellowstone in 1959 which is somewhat before modern fracking started

You can read it all about it here ;

Oh deary me, pants on fire

Featured Image -- 1005

It does seem to me that fractivists wear very Hot Pants and possibly the fire is fuelled by CH4.

If this was a one-off it would be forgiveable, but porkies like this are the staple fare of so much anti-fracking literature put out whether in print or in the aether.

It seems that this…

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Creationism in schools; the myth of the “isolated incident”

It recently emerged (see Jonny Scaramanga’s post, shown below) that Durham Free School was teaching creationist doctrine, based on the explicit creationist claim that the Solar System is so well suited to intelligent life that it must have been designed by God, complete with reference to the eclipses He has so thoughtfully provided for the edification of astronomers:

When the _____ comes between the earth and the Sun, there is an _____ . There are ____ going round the Sun. Only Earth has life on it. God has designed the Solar System so that Earth can support life. For example, Earth is the right _____ from the Sun, so that we are neither too hot nor too cold. Our moon is big, which stops us from wobbling.Comets and asteroids which could destroy Earth are mopped up by planet _____ before they get to us.

An isolated incident? Not really. Durham Free School has (or had; it is closing at Easter) numerous problems, being described by a local MP to the BBC as a “haven for crap teachers”. My friend Jonny Scaramanga has now discovered that the individual teacher concerned has a track record of creationist teaching, and gives all the details in a blog post on Patheos, which with his permission I reproduce below. This is far from the first case where schools set up by obviously creationist groups have had to be shut down in short order, or even failed to take off altogether; consider for example al Madinah and, in its many reincarnations, Everyday Champions.

So when we learn, as we are learning, that creationist groups such as Apex Church and York Street Hall in Peterhead are infiltrating schools, it is no surprise to discover multiple links between these schools and other fundamentalist groups; for the full Scottish Secular Society response to these disclosures, see here.

The official Scottish Government position is that incidents such as the Kirktonholme scandal were isolated, and that no official action or guidance on creationism is needed. I see no reason to believe this cheerful conclusion as regards Scotland, any more than it would have been correct if applied to England. Do you?

And one unfortunate difference is that while aggrieved parents in England can appeal to official guidelines, the Scottish Government has so far resisted giving any such advice.

Regular readers will know that the Scottish Parliament’s Education and Culture Committee will be considering the matter on March 10th (see here and here). We look forward to their deliberations, and to the Government’s response, with interest. 

State-funded school in Durham, England employed a creationist science teacher

Schools Week carries the exclusive news that Durham Free School gave students a science worksheet that said “God has designed the solar system”. The local newspaper reports that parents are justifiably outraged.

I’ve done some Internet sleuthing, and it looks like the science teacher in question has a long history of teaching at creationist schools. It’s against the law for Free Schools in England to teach creationism. If the teacher, David Hagon, has indeed taught creationism as science in his past roles, it must be asked how he was given the job at Durham Free School.

Image from I believe its inclusion here constitutes Fair Use for critique. What is it with creationists and their obsession with fill-in-the-blank exercises? Content aside, this is awful pedagogy.

From the article:

Schools Week has discovered David Hagon, a teacher at the school, in September asked year 7 pupils to complete a worksheet as part of their science homework that stated God was responsible for the design of the solar system.

The worksheet (pictured) said: “Only the Earth has life on it. God has designed the solar system so that the Earth can support life.”

Any school, academy or free school that is found to teach creationism as a scientific fact would be in breach of the law and its funding agreement.

A spokesperson for Durham Free School said: “Legitimate concern was raised over this matter as the worksheet was in clear contradiction of the school’s policy and practice.

“It was an isolated incident, which the former headteacher dealt with promptly, firmly and appropriately; the worksheet is not used by the school.

Durham cathedral pictured from the river. Photo by Wiki Commons user jungpionier. Creative commons.

An isolated incident? According to the Northern Echo, a parent claimed otherwise. It all seemed fishy to me, so I searched online for the phrases “David Hagon” and “Christian school”. I just had a hunch.

I found this:

STAFF, parents and pupils at a Sale-based Christian school are celebrating after receiving a glowing report from Ofsted.

Inspectors visited Christ the King School in November last year and returned complimentary findings about the institution’s provision of spiritual, moral, social and cultural development and pupils’ outstanding behaviour.

Accompanying the article is a photograph of a staff member with the students, and the caption reads “Deputy Head David Hagon with some of the pupils”.

Two questions then arise:

1) Did Christ the King School teach creationism?
2) Is this the same David Hagon that has recently taught at Durham Free School?

1) Yes. CTKS (which closed in 2008was a member school of the Christian Schools Trust (CST), a network of private evangelical schools in the UK. Sylvia Baker was one of the founders of the CST, and she produced a PhD thesis about it. Here are some notable quotations from that thesis:

The [CST] schools may well constitute the only setting within the United Kingdom where science education is approached within a creationist framework. [pp. 150-151]

The teaching of creationism as an alternative to the theory of evolution constitutes one of the most controversial issues involving the new Christian schools. Walford (1995a, p20) investigated 53 of the schools in 1993 and found that the teaching of creation and evolution was one of their distinguishing features. This has been confirmed by a recent investigation involving the schools which took part in this survey, as described in Chapter 3. The Christian Schools Trust statement on the teaching of creationism and intelligent design (see Appendix 3) clarifies the approach that the majority of the schools are taking. [pp.160-161]

The schools themselves claim that, in addition to placing all of their educational practice within a Biblical creationist framework, when it comes to science education they teach creationism alongside evolution as a debate. [p. 166, see also p. 168]

Appendix 3 then contains a statement, agreed by all member schools of the CST, which as my friend and colleague Paul Braterman puts it, is “a skilfully crafted instrument for teaching evolution in such a way that it will not be believed”.

So a David Hagon was the deputy head of a school that undoubtedly taught creationism as science.

2) Was it the same David Hagon teaching at Durham Free School?

Probably. I can’t prove he is, but it seems only a remote possibility that there could be two creationist David Hagons. I did a search on the Electoral Roll for David Hagon. In the 2002 register, there were 19 matches (the most of any year); for 2015, just 11. According to British Surnames:

There are approximately 852 people named Hagon in the UK. That makes it the 7,920th most common surname overall. Out of every million people in the UK, approximately 13 are named Hagon.

Given what a small minority creationists are in England, it’s not massively likely that there are two creationist science teachers called David Hagon, is it?

Hopefully, a Durham Free School parent or pupil will be able to look at the photo from Christ the King School and confirm whether this is indeed the same David Hagon.

I’m not finished. Google has another match for “David Hagon” and “Christian school”, and it’s from Emmanuel College in Gateshead. According to the article, someone named David Hagon was “Head of Electronics” at the school.

The name “Emmanuel College Gateshead” may ring a bell for you. That’s because it was embroiled in a massive row over creationism. Scientists both Christian (John Polkinghorne) and atheist (Richard Dawkins) criticised the school’s science teaching, and it was noted that the school had allowed its hall to be used for an Answers in Genesis meeting. The school’s head of science, Steven Layfield, had previously been a director of the creationist organisation Truth in Science.

So if I have correctly identified this David Hagon, he has previously been in a senior position at one private school where creationism was explicitly taught, and one state-funded academy where it was allegedly taught. Yet somehow he was teaching science at a Free School where it is a condition of the funding agreement that creationism is not taught as science. It looks something went badly wrong with the vetting procedure for staff at Durham Free School.

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