SciBlogs

aquatic apes & custard elephants Alison Campbell May 14

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The ‘aquatic ape’ hypothesis (it can’t be described as a theory) has been around for quite a while, & in fact I’ve blogged about it before. So I was sorry to hear that Sir David Attenborough, who’s done so much to promote conservation issues and enhance our understanding of the natural world, appeared to have given the idea some support. He’s certainly taken some flak for this (see here, for example), although at the same time other – ahem! – news outlets have picked up the ball and trotted off down the garden path with it.

Briefly, the aquatic ape hypothesis (I will NOT call it a theory) purports to explain the evolution of a number of aspects of our morphology: our relative hairlessness & the distribution of that hair, bipedalism, the way so many people like fish (I will put my hand up as an exception to this), distribution of body fat, & so on. ** Unfortunately for this particular just-so story, there’s good evidence that all these features did not evolve at the same time. Bipedalism, for example, pre-dates the chimp-human divergence, but the addition of fish to the diet seems to have appeared much later. Nor is there necessarily strong evidence of any links between a particular feature & the life aquatic. For example, while cetaceans are essentially hairless, seals, sealions and their relatives are covered with dense coats of fur.

Anyway, the hypothesis has recently been the focus of some entertaining parodies, among them the ‘space ape’ version (face-to-face copulation would really have been the only option, dontcha know? for otherwise the jetpacks would get in the way) and – as a conclusion to his explanation of why the aquatic ape idea doesn’t stack up – Henry Gee’s thought experiment involving the unlikely combination of elephants and custard.

Enjoy.

** “& so on” includes the sinuses in our skulls (another feature that reinforces our African origins). Apparently they provided a buoyancy aid – yet they’re found in all mammals regardless of habitat.

[EDIT] However, courtesy of one Smut Clyde I find that the aquatic ape proposal has nothing on this.

 

 

 

 

 

 

 

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selling services on-line Alison Campbell May 13

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Yesterday’s Sunday Star-Times carried the headline: Chinese cheats rort NZ universities with fakes. The story begins:

An investigation has uncovered a well-organised commercial cheating service for Chinese-speaking students in New Zealand. The long-standing business uses a network of tutors, some outside New Zealand, to write original assignments ordered by Chinese-speaking students attending New Zealand universities, polytechnics and private institutions

and provides a link to an essay bought by the reporting team as part of their investigation.

Frankly, about the only thing that surprised me about the story was the fact that the organisation delivering this ‘service’, and thus helping those using it to cheat, is based in New Zealand. I mean, I’ve just had one of my regular clean-outs of the spam folder. Anything there just gets deleted; there’s so much coming in that I don’t have time to scan it just in case a genuine commenter has been dumped there. But occasionally something at the top of the queue for oblivion catches my eye, and I notice things like this:

Lately, graduates are overloaded to produce essay writing, they can find custom writing services where they are able to buy critical analysis essays.

If you are desperate, you always have a possibility to purchase high quality essay and all your problems will disappear.

Are willing to be a good student? Therefore, you should realise that good high school students buy paper and if it is fits you, you can do the same!

And the icing on the cake:

Some people have got a passion of composing academic papers, but, some of them do not know the correct way to complete research papers. Professional Custom UK Essay writing service is developed to help students who cannot write.

Frankly, the standard of English in that lot should put potential buyers off! At least some of the time they make an attempt at ‘buyer beware’ (but don’t you just know that the following would link to one of these ‘good’ sites?):

If you want to escape any troubles while ordering essays at the paper writing services, you ought to be really thorough. Buy essay services only if you have solid evidences that the people you’ll be dealing with are highly educated.

Lols aside, there’s obviously a market for this sort of stuff; it’s worth pondering why students would buy in work, and what options teaching staff have for avoiding/reducing the temptation.

One obvious motivation is the pressure to do well. Students (& often their families) do invest quite a bit of money into their education. This is particularly true for many international students whose families spend a lot to send them here & support them during their studies. (So do taxpayers, via the student loan system, so we – ie taxpayers – do need to know that we’re getting good value there, & that includes the quality of students’ work.) So fear of getting a poor mark, & perhaps having to repeat a paper, could drive the sort of behaviour that our spammers and the Auckland organisation are hoping to generate.

And unfortunately ‘custom essays’ are not going to be picked up by anti-plagiarism software (eg Turnitin) – unless the ghostwriters are stupid enough to just do a copy-&-paste! That’s not to say they can’t still be identified: an obvious clue would be a standard of English that differed significantly from that in other work submitted by a student; the relevance of the actual content would be another.

But there are ways of reducing incentives to be dishonest around assessment. For example, teachers can review their use of ‘high stakes’ assessment items: single essays or reports that are worth a large proportion of the final grade (& so can offer some incentive to cheat in order to gain a higher mark). ‘End-loading’ assessment, so that it’s all due at the end of semester, is not going to help here either.

Another tool would be to have students generate work in class. Now obviously that won’t work if you want a lengthy report, but what about: getting them to do the relevant research but asking for them to write an abstract, or a summary of their findings, in-class, & having it peer-marked (using your marking scheme) or doing that task yourself? The students still gain practice in useful skills & – hopefully – your workload is somewhat reduced. If students get more involved in the writing process from the start, & are supported in learning the various skills involved, they might be more confident in their own abilities & feel less need to cheat on the assignment.

Recommended reading**:

J.C.Bean (2001) Engaging Ideas: the professor’s guide to integrating writing, critical thinking, and active learning in the classroom. Jossey-Bass (Wiley). ISBN 978-0-787-90203-2

** actually, make that highly recommended!

`~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

And in today’s spam (May 20) – how blatant can you get?

Nowadays you shouldn’t give your best shot in order to come up with quality academic papers since online writing services are willing to provide you with professional assistance. Buy essay example and get out of hard writing assignments.

 

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the gastric-brooding frog – not quite back from the dead Alison Campbell May 08

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I first found out about gastric-brooding frogs (Rheobatrachus silus) when reading Stephen Jay Gould’s essay “Here Goes Nothing” (as published in the 1991 book Bully for Brontosaurus). As he said, these frogs really do live up to their name: the frog

swallows its fertilised eggs, broods tadpoles in its stomach, and gives birth to young frogs through its mouth.

Gould’s tale first introduces another example of the ability of natural selection to shape truly strange behaviour: male Rhinoderma darwini frogs swallow the eggs they’ve fertilised and brood them, not in their stomachs, but in their throat pouches. These are the same pouches that male frogs inflate with air & use in croaking (& whistling, & chirping, depending on species) during courtship, which means that a brooding male is rendered voiceless for the duration. However, it doesn’t stop them feeding normally, something that was first demonstrated way back in 1888 by biologist G.B.Howes (Gould, 1991). I was interested to find out, while researching this post, that the eggs aren’t ingested immediately after fertilisation: they’re laid in damp leaf litter and the male remains close by, but waits until the embryonic tadpoles are wriggling around inside the egg membrane before taking them up in his mouth. (I’m guessing that the behaviour’s triggered by the sight of the wriggling tadpoles.)

As for the gastric-brooding species: Gould provides an engaging description of how this habit was uncovered. Until 1979

[n]atural birth had not yet been observed in Rheobatrachus. All young had either emerged unobserved or been vomited forth as a violent reaction after hatching.

However, scientists finally managed to get a gravid (I hope that’s the right word in these circumstances!) female in an aquarium with their cameras all at the ready:

The mother “partially emerged from the water, shook her head, opened her mouth, and two babies actively struggled out.”

It’s no small feat to incubate froglets in this way:

This… female, about two inches long, weighed 11.62 grams after birth. Her twenty-six children weighted 7.66 grams, or 66 percent of her weight without them.

And of course, the incubating female must stop eating and switch off production of gastric juices for the duration!

Sadly, confirmation of this highly unusual method of parental care was rapidly followed by news that the species appeared to be extinct in the wild. Which is why I was so intrigued by my student’s news of its resurrection. However, it seems that reports of that resurrection may have been somewhat exaggerated. A quick search turned up several articles (this one’s a good example) that describe what’s been achieved so far: R.silus tissues that had been in the freezer were thawed, and cell nuclei from those tissues were implanted in enucleate eggs from another, distantly-related, species of frog (an example of somatic cell nuclear transfer). Some of those went on to an early (but unspecified) stage of embryonic development before being frozen in their turn, to await possible reanimation in the future.

In other words, R.silus froglets won’t be hopping around just yet. (And I’m moved to wonder how achievable the aim of the Lazarus project actually is, as it relates to this species. After all, if the gastric brooding part is an essential part of development, where’s the stomach going to come from?)

S.J.Gould (1991) Bully for Brontosaurus. Penguin Books.

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see-through creatures Alison Campbell May 08

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This is a ‘glass frog’ (image from National Geographic):

It’s one of a number of transparent or translucent creatures featured on the National Geographic’s “Weird & Wild” blog. (Actually I take issue with the Monarch butterfly image there, as strictly speaking we’re seeing a transparent pupal case; the butterfly inside is definitely not see-through.)

Glass frogs (Hyalinobatrachium pellucidum) are on the ICUN’s ‘red’ list as an endangered species, with habitat destruction the likely cause. However, if chitrid fungi are introduced to the frog’s limited range  - they’re recorded from only five locations on the Amazonian slopes of the Andes in Ecuador – then the population will likely decline even faster (always supposing this particular pathogen isn’t already there). These delightful little frogs are apparently about the size of a fingernail, & their translucency is due to a lack of pigment in the skin. Not only can you see the air-filled lungs, the red threads that are blood vessels, and the heart with some of the major arterial arches clearly visible – you can also see the animal’s skeleton.

And that reminds me: we were talking in class the other day about gastric-brooding frogs & one of the students said they’d heard that this species had been cloned. An intriguing possibility – I must go off & look into it!

 

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tool use – even more widespread than you thought Alison Campbell May 07

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Yesterday my ‘Facebook science feed’ (ie daily browsing) brought me this stunning image (click the picture for the hyperlink). It’s from the book Thinkers of the Jungle: the Orangutan Report (Shuster, Smits & Ullal, 2008) & shows a young orangutan apparently using a long stick in lieu of a spear, copying local fishermen as they hunted with spears. (It’s been blogged about here by Kambiz Kamrani.)

Which is pretty darned amazing. Tool use, & various tool cultures, are now quite well-documented in our nearest living relatives, the chimpanzees, but this is the first time I’d heard about it in a wild orangutan. Also novel: the concept that another great ape might also sometimes eat vertebrates (again, well-documented in the members of some chimpanzee troops). So I decided to dig a little deeper.

It turns out that orangutans do on occasion eat meat, although reports of this are rare. Back in 1997 Sri Suci Utami & Jan van Hooff reported on a total of seven incidents of carnivory by three different female orangutans in Sumatra. More recently Madelaine Hardus & her colleagues (2012) looked at a few additional instances of this behaviour – which in all recorded cases has female orangutans doing the eating and slow lorises as the prey – and considered whether it might be seasonal and related to the availability of other food sources (they felt that it was). Both research teams characterised the behaviour as opportunistic as there was no evidence of any organised hunting activity: it was more a case of a foraging orangutan happening across a slow loris. And they noted that the data are too few to allow any firm conclusions about either the frequency of this behaviour or whether it might be skewed towards one gender or the other.

Nor was this the first documented example of tool use by these Asian great apes. While it’s apparently well-known in captive animals, Carel van Schaik first documented this behaviour among wild-living orangutans back in 1994, in Sumatra (apparently it’s not been observed in populations from Borneo). The animals he was watching were in relatively high densities and surprisingly tolerant of each other – plenty of opportunity to watch and learn from the activities of others, which may be why tool use hasn’t been seen in the wild in Borneo, where the animals are much more widely dispersed).

van Schaik documented the use of sticks to prise open extremely prickly fruit in order to get at the soft flesh within, but more recently he and a group of co-workers provided evidence that, like their cousins the chimps, orangutans in different areas have developed different cultures (around behaviours broader than simply using tools). Which demonstrates (again) that culture is not something that is solely ‘ours’, and suggests that such behaviour may have been around for a very long time indeed, given the antiquity of the split between the lineages leading to modern orangutans and (eventually) Homo sapiens. As van Schaik and his team concluded:

Hence, great-ape cultures exist, and may have done so for at least 14 million years.

 

M.E.Hardus, A.R.Lameira, A.Zulfa, S.S.Utami Atmoko, H.de Vries & S.A.Wich (2012) Behavioural, Ecological, and Evolutionary Aspects of Meat-Eating by Sumatran Orangutans (Pongo abelli). International Journal of Primatology 33: 287-304. DOI: 10.1007/s10764-011-9574-z

S.S.Utami & J.A.R.A.M.van Hooff (1997) Meat-Eating by Adult Female Sumatran Orangutans (Pongo pygmaeus abelli). American Journal of Primatology 43: 159-165

C.P.van Schaik, M.Ancrenaz, G.Borgen, B.Galdikas, C.D.Knott, I.Singleton, A.Suzuki, S.S.Utami & M.Merrill (2003) Orangutan Cultures and the Evolution of Material Culture. Science 299 (5603): 102-105. DOI: 10.1126/science.1078004

 

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science challenges & science education Alison Campbell May 02

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The National Science Challenges have been announced – and have already received a lot of attention (including on Sciblogs, with posts by my colleagues Grant, Siouxsie, and John - who also points at where the money’s going). What I’d like to address here is the comment by the Panel that it

was concerned by the lack of significant proposals in educational research

I have to admit that my first response to that was, well d’oh! Because, well, the public discussion was around national science challenges, I suspect that for many (most?) submitters the focus was to come up with a science-based proposal. After all (& please note bulging cheek ensconcing my tongue at this point), isn’t science education something that schools & other seats of learning ‘do’, rather than requiring science research? Hopefully not many scientists really think that way, & it’s great to see the additional Challenge, “Science & New Zealand Society” with its two goals (the first a science goal, while the second is societal):

To ensure the science capacities and literacy of New Zealand society so as to promote engagement between S[cience] & T[echnology] and New Zealand society, in turn enhancing the role played by science in advancing the national interest.

To allow New Zealand society to make best use of its human and technological capacities to address the risks and Challenges ahead. This requires the better use of scientific knowledge in policy formation at all levels of national and local government, in the private sector and in society as a whole.

 

Both are relevant to what follows here.

Let’s look more closely at the question of science literacy/appreciation/education for citizenship. The chair of the Panel, Sir Peter Gluckman, has previously made it clear that we need to do much more in engaging young people with science, to the extent of developing a science curriculum that focuses far more on science literacy than on accumulation of science knowledge. But what constitutes science literacy? This is something I’ve written about previously, & my fellow Scibloggers and I discussed it between ourselves more recently. So I was interested to find a set of nine science literacy ‘themes’ listed and expanded upon in a recent paper (Bartholomew & Osborne, 2004):

scientific methods and critical testing

science & certainty

diversity of scientific thinking

hypothesis and prediction

historical development of scientific knowledge

creativity

science and questioning

analysis and interpretation of data

cooperation and collaboration in the development of scientific knowledge

And while we might not agree on the relative order of these themes, or the completeness of the list, but they do give us something to go on with. (I’m going to talk about the formal education system for the moment – but I’m perfectly well aware that there’s much more than that to public engagement with science! Let’s just treat this as a starting point for discussion.)

Now, I’d like to think that the current NZ Science curriculum gives a good basis for developing these skills & attributes in all students Right Now, regardless of whether or not they intend to go on to study science at tertiary level. And let’s face it, most won’t, so we surely have to work on engagement with and understanding of what science is about, for all students. in fact, that’s a tension I struggle with myself: a proportion of my first-year biology students are taking the subject purely for interest, & in some cases haven’t studied the subject before. I want them to come away with an appreciation of the wonder and worth of the subject in their lives, as much as I want them to accumulate biological knowledge. It’s a tricky balancing act.

Anyway, while I might like to think that about the curriculum document, in reality I suspect that it doesn’t yet deliver. And that’s something that’s unpacked further by Bartholomew & Osborne, who note that there are a number of factors that affect teachers’ “ability to teach effectively about science”.

One of those factors is the teachers’ own understanding of what science is all about, as opposed to their body of content knowledge. NB Please note, at this point, that this is not a criticism of teachers and the demanding work that they do; it’s a question of whether the training and experiences we offer our teachers prepare them well for this particular aspect of teaching science.

The researchers found that a reasonable proportion of the teachers they worked with were not really confident in their own ability to teach lessons based on the ideas embedded in those themes. This was partly due to uncertainties about their own knowledge, and partly around feeling that they lacked the classroom skills to deliver such a program. Which, of course, raises issues around provision of professional development opportunities (with the associated resourcing).

Related to that is their own engagement with the subject. OK, if you’re teaching the subject as a specialist science teacher, I’m guessing that you took this role on because you enjoy the subject and want to share that. But if someone’s a primary school teacher with very limited exposure to science during their training, then the story might be very different.

And so that would be a fruitful area for research, in NZ (and at this point someone is probably going to tell me that they’re Already Doing It): what is the actual level of science literacy – using, for example, those 9 themes listed above – in NZ science teachers at all levels? And how does that translate into classroom practices? And – if the answer is, not as well as we’d like – what do we do about it?

Teachers’ ability to enhance learning about science (as opposed to of science) is also affected by factors outside their classrooms. For example, the pressure is on, at senior school level, to ensure students do as well as possible in national assessment – which, for all the changes associated with NCEA, remains largely content-based. And classroom time is limited, so it’s easy to see how there can be more focus on content & less on the other desirable attributes. As Bartholomew & Osborne comment,

developing a questioning and sceptical attitude to scientific knowledge claims in students might actually be disadvantageous.

Perhaps that also needs to change. [Pace, Schol Bio examiners!]

 

H.Bartholomew, & J.Osborne (2004) Teaching students “ideas about science”: five dimensions of effective practice. Science Education 88: 655-682 doi: 10.1002/sce.10135

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true facts… Alison Campbell Apr 26

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OK, you could argue that you can’t have a ‘false’ fact :) But that aside – I was recently introduced to this little gem of a video, True Facts About The Chameleon. Nice little sound-bites of information, rather lovely images – and the narrator’s voice-over had me in stitches. (But he’ll never replace Sir David Attenborough!)

Enjoy! (I’m going to sit & see what else he has to say about praying mantids: I’ve already heard the bits about having puppydog eyes and complex mouthparts that include “a moustache beneath [its] mouth – made of fingers” – a novel take on the animal’s lower ‘jaw’.)

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a little extrapolation is a dangerous thing Alison Campbell Apr 19

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The other day one of my friends sent me a link to this discussion of a recently published paper. (‘Published’ in the sense that it’s available through archiv arXiv, which I gather means it hasn’t been through peer review.) The actual paper is available here. Basically, the authors claim that life has increased in complexity – they’ve used genome size as their measure – as it’s evolved, and that extrapolating that trend backwards suggests that life evolved prior to the formation of the solar system.

But is genome size a particularly good proxy for complexity? Here’s the graph that underpins the conclusions reached by Sharov & Gordon:complexity vs time.jpg

Do you see what they’ve done there? ‘Worms’ – which worms? For after all, there are a lot of them: at least 10,000 species of flatworms, more than 80,000 species of roundworms (aka nematodes), and another 10,000 or so annelids (including the familiar earthworm), not to mention the less familiar taxa such as velvet worms & the priapulids. As for the arthropods – well, good old Daphnia has more functional genes than we do. (The poetical Cuttlefish has a nice take on this story here.)

And I see that plants & protists have been left out altogether – unless they’ve been lumped in under the general heading ‘eukaryotes’. Which is strange, because the overall genome size varies by 5 orders of magnitude** across the eukaryotes so far studied, so using a whole bunch of data points instead of the collective average, would make more sense. Unless that would spoil the nice straight line? (**Having said that, much of that variation is due to the number of introns & the quantity of non-coding DNA; however, the various regulatory sequence regions must surely come under the authors’ heading of ‘functional non-redundant genome’?)

I had also thought, on reading the review, that we were probably looking at an argument for panspermia. And I was right. This and other conclusions are presented in the abstract, & I note a certain amount of hubris in the assumption that humanity represents the only possibility of intelligent life in our universe (my emphasis).

(1) life took a long time (ca. 5 billion years) to reach the complexity of bacteria; (2) the environments in which life originated and evolved to the prokaryote stage may have been quite different from those envisaged on Earth; (3) there was no intelligent life in our universe prior to the origin of Earth, thus Earth could not have been deliberately seeded with life by intelligent aliens; (4) Earth was seeded by panspermia; (5) experimental replication of the origin of life from scratch may have to emulate many cumulative rare events; and (6) the Drake equation for guesstimating the number of civilizations in the universe is likely wrong, as intelligent life has just begun appearing in our universe.

A.A.Sharov & R.Gordon (2013) Life Before Earth arXiv:1304.3381v1  

PS Strangely, in a paper supposedly about biological evolution, the latter part of the article goes on to discuss technological (ie cultural) evolutionary change – I’m not convinced that it’s appropriate to segue between a claimed link for genetic complexity & time, into the undoubted complexity and rapid ‘evolution’ of technology; apples & oranges, guys.

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‘new zealand’s #1 way to lose weight’ – oh really? Alison Campbell Apr 02

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As I’ve said previously, I find Facebook good for keeping up with friends & family, & profoundly irritating in its practice of ‘targeting’ ads to the user. Mind you, that offers endless opportunities for blogging (when one can find the time). And today I shall make use of that opportunity, for today FB offers me a link to “New Zealand’s #1 way to lose weight” – and no, it’s not a combination of exercise & eating sensibly!

First up, although the purported writer claims to be a New Zealander looking at use of a particular ‘miracle’ combination in NZ & documenting her own results, I couldn’t help but notice that a) ‘New Zealand’ is mentioned but a single time in the blurb; b) she looks nothing like any of the women in her supposed ‘before & after’ photos (nor does she share a name with any of them – such sloppy editing, lol); & c) none of the women are from NZ.

Anyway, what’s she raving about? There seems to be a new ‘miracle weight loss/elixir of health’ offered every week (there’ve been ads pushing reservatrol in the papers recently, for example). This particular wonder is the fruit of Garcina cambogia (aka Gambooge), native to Indonesia but grown through South-east Asia and parts of India & Africa, where it’s widely used in cooking. However, it’s also been claimed to have significant health benefits: the page FB promotes says

It is known to contain the highest antioxidant concentration [not according to this study]  of any known food, and is reported by many to have unprecented weight loss and health benefits. By combining Garcinia Cambogia [sic] supplements with a natural colon cleanse…, many people claim that their bodies have literally become “fat burning machines”.

Ah, the wonders of pseudoscience – oxidation is required to ‘burn’ fat, so promoting an antioxidant to help lose fat sounds somewhat contradictory :) And colon ‘cleanses’ – money down the loo.

As for that claimed weight loss (the promotional web page claims 13 kgs!), well, the value of G.cambogia in achieving this has been put under the microscope. This approach is rather more reliable than relying on testimonials, even celebrity endorsements: like green coffee beans, gambooge has been promoted on Dr Oz’s TV show as a “revolutionary” new fat buster.

Yet it isn’t even new – its use has been studied for over 15 years. A study examining its potential as an anti-obesity agent, published back in 1998, concluded that

Garcinia cambogia failed to produce significant weight loss and fat mass loss beyond that observed with placebo.

And this meta-analysis of randomised clinical trials – published in 2011 – found that Garcinia extract (hydroxycitric acid) might cause short-term weight loss. However, they noted that in one trial those using the extract were more likely to suffer gastrointestinal upsets than people on a placebo, and went on to conclude that

The magnitude of the effect is small, and the clinical relevance is uncertain. Future trials should be more rigorous and better reported [my emphasis].

I’ll stick to the exercise/sensible eating combo – it’ll probably save me money too :)

 

S.B.Heymsfield, D.B.Allison, J.R. Vasselli, A.Pietrobelli, D.Greenfield & C.Nunez (1998) Garcinia cambogia (Hydroxycitric acid) as a potential antiobesity agent: a randomised controlled trial. JAMA 280 (18): 1596-1600. doi: 10.1001/jama.280.18.1596

I.Onakpoya, S.K.Hung, R.Perry, B.Wider & E.Ernst (2011) The use of Garcinia extract (hydroxycitric acid) as a weight-loss supplement: a systematic review and meta-analysis of randomised clinical trials. Journal of Obesity 2011. doi: 10.1155/2011/509038

 

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caesarians & medical hypotheses Alison Campbell Apr 01

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Many moons ago I used to do the occasional talk for Parents Centre ante-natal classes, on what to expect during a caesarian delivery. (I’d experienced an emergency C-section, so was happy to let others know what was involved.) So it was to be expected that this op.ed piece in today’s NZ Herald (in the “Life & Style” section) would catch my eye. Initial interest turned to a thought that perhaps I was reading a spoof (check the date), but the paper described in this article does exist.

In January 2012 we brought together eleven researchers (midwives, scientists, epidemiologists, geneticists and epigeneticists) at the University of Hawaii and developed the EPIIC Hypothesis, which has just been published in Medical Hypothesis.

I did wonder in passing why epidemiologists & geneticists weren’t counted as scientists, but what stood out is the fact the paper was published in Medical Hypotheses. (Being charitable, I’ll assume the mis-spelling occurred in the editorial process.) In other words, there’s no requirement to present any data in support of the hypothesis under discussion.

We have known for a while now that caesarean section is linked to longer-term health implications for the child…

As one of the commenters on the Herald piece points out, correlation is not the same as causation. Surely the researchers are aware of this?

We hypothesise that events during labour and birth – specifically the use of the synthetic hormone oxytocin, along with antibiotic use and caesarean sections – affect the epigenetic remodelling processes and the subsequent health of the mother and child.

Oxytocin is produced in large quantities during a normal labour; what would be the impact of that on epigenetic changes around the time of birth? In fact, the authors point the finger at more than (synthetic) oxytocin & C-sections, including forceps & vacuum-assisted deliveries as those potentially exerting a harmful effect. In describing this hypothesis, the op.ed. writer seems to be ignoring the fact that in at least some cases not using those interventions could result in the considerably more harmful outcome of death for mother &/or child. (To be fair, things are narrowed down somewhat in the MH paper.)

In the EPIIC hypothesis, we propose that physiological labour and birth have evolved to exert eustress (a healthy, positive form of stress) on the fetus, and that this process has an epigenomic effect on particular genes, particularly those that programme immune responses, genes responsible for weight regulation, and specific tumour-suppressor genes.

This is an interesting use of the term ‘eustress’, since its definitions suggest that whether or not stress is ‘healthy’ depends on how the individual perceives that stress, & whether they are left with a ‘feeling of fulfilment’ after experiencing it. At what point would a ‘normal’ labour cease to be so, & start generating ‘non-healthy, negative’ forms of stress?

And how would this hypothesis be tested? The Medical Hypotheses paper (sorry; it’s behind a paywall) does suggest a possible research program: essentially a long-term project tracking outcomes in individuals who birth experiences range from

home births in the most familiar environment to the woman and without medical interventions … to those born after elective caesarean section for breech presentation where there are no underlying medical complications…

and including

various ethnic groups, gestational ages, maternal ages and socioeconomic backgrounds.

With so many variables listed, proper data collection & analysis would be an extremely complex task. There is no mention of how this might be properly blinded. And – as that same Herald commenter says – why not go for an animal model first? And publish the results in a mainstream journal?

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