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perhaps the most inspiring graduation address i have ever heard Alison Campbell May 21

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At the recent graduation ceremony for students from Waikato University’s Faculty of Science & Engineering (& those from its sister Faculty, Computing & Mathematical Sciences), we were privileged to hear an absolutely inspirational address from the recipient of an honorary Doctorate at that ceremony: Dr Gordon Stephenson. And I mean, inspirational! After the event I spoke with Dr Stephenson & asked if he’d be willing to provide the text of his speech, because I believed it deserves the widest possible audience, and he was kind enough to provide me with a copy. (I’ve taken the liberty of adding a hyperlink in a couple of places, for those who may not be familiar with some of the references.)

  

Chancellor Rt Hon Jim Bolger, Vice chancellor Professor Roy Crawford, academia, distinguished guests, students at all levels, my whanau, everyone.

This really is an extraordinary and totally unexpected honour that you have bestowed upon me. I find it very difficult indeed to adequately express what it means to me.   

When my daughter Janet handed me the letter from the University on Christmas day, she says it is the only occasion she has seen me speechless. I was truly gob-smacked ! So I will just say ‘Thank you’.

It is actually somewhat ironic, because in the late 1940’s, as a returned serviceman, I took a BSc (Agric) at Reading University, England, and passed with a ‘C’ grade.

But life was too full as a student, what with sport, starting an agricultural journal, getting married to a beautiful civil engineer  graduate of London University, living on a small boat, and many other activities better left unsaid, such that the ambition to attain a First Class Honours degree went by the wayside.

I did, however, become infected with the stimulating topic of science. Even as a 10 year-old, I pored over nature magazines. I still have some of them.

But I left university puzzled. I had been taught things which just did not make sense, such as the idea that mountain formation was due to shrinkage of the earth’s surface, while the concept of so-called continental drift was anathema. And the explanations of  heredity were far from complete or even believable.

It got me thinking about ‘truth’ and the realisation that truth is only that which is the current knowledge and thought, and that it is constantly being replaced with new ideas. And where do ‘facts’ tie in with ‘truth’?.

We moved to Waikato in 1960, and I have followed with interest the development of this University from paddocks to a landscaped campus. Your reputation has grown, and you can now boast of being a leader among NZ universities in the particular disciplines you have chosen to develop. Congratulations.

Universities have critical roles in society.

Research is a heavy responsibility. It is actually a huge privilege to be paid to research. You are a repository of knowledge, not only in your libraries and theses, but also in the research-based understanding lying in the minds of academia.

Then there are your teaching responsibilities, hence all these wonderful students hopefully fired by your inspirational lectures. I know I was by some unforgettable tutors.

But there is another responsibility, which I often feel is not adequately addressed. This is the role of a university as the public conscience.

It has long perturbed me that the public battlers and advocates for a better society are almost all lay people or NGO’s, whereas those very issues are probably being studied in depth in this institution.

It takes courage to step out beyond the walls of the campus and into the hurly-burly of controversy. There are noble examples at this University, and they will know to whom I refer, but I’ll mention one from Waikato, the late much-loved Dr Charlotte Wallace.

Besides being an assiduous researcher of snails, she was totally fearless in her environmental advocacy, and greatly admired and respected as a result. She virtually started, decades ago, the South Auckland Conservation Association. She made a difference.

We look to the Universities to be the champions, the leaders, for the big issues facing us. You have the knowledge. Please, make sure it is put to good use.  

I turn now to you graduates of all disciplines and interests.

I was born in 1924 (I can see you all doing some rapid mental calculations). In that year, there were only two billion people on earth.

Now, in this one person’s lifetime, that has more than tripled. There are three people alive now for every one alive then. Picture if that were to happen to you all present here in the world of 2013. It would seem impossible.

So believe me when I say that maybe I can personally appreciate the creaks and groans of poor old mother earth, and the pressures and stresses placed upon the populace and natural systems.

There are the issues such as climate change, peak oil, the health of the oceans, extinctions and the loss of biodiversity, the rush to urbanization, rising sea levels, let alone the forecasted inability of farming to feed the projected ten billion people.

We ignore at our peril the intricate web of millions of species whose interactions create our living conditions. We have a lamentable inability to recognise the implications of exponential growth, and the menace of the bell curve. The downside of that curve will turn round and bite.

These matters are all interconnected, and cry out for solutions that are also interconnected. My generation has failed to find those solutions, or, where they are blindingly obvious, failed even more miserably to implement them.

Many of these issues were faced by Maori some 5-600 years ago. Their previously known world of easily harvested fish and birds suddenly faced the impacts of resource depletion. Their reactions paralleled those that arose centuries or millennia before in many parts of the world.

Their first reaction was war, to safeguard their food supplies and other resources. The other reaction, to their great credit, was to impose upon themselves strict rules of harvest, through such mechanisms as rahui. There are lessons there for humans everywhere.

And so I look to you, our next generation, to whom we dodderers bequeath our one-and-only beautiful and magical earth. In some ways, it matters little the topic you studied here.

You have, I trust, been taught by this University to think, because you will need to use those analytical skills that are so necessary in any field of study, for the massive tasks you face ahead. You have to persuade both the wider population and the decision makers, of the root problems we face. There are doubters galore, both for commercial and political reasons or because of reluctance to face facts.

The centuries-old saying is ‘There are none so blind as those who will not see’. You have an absolutely necessary task ahead, which may seem daunting, and you may react by thinking ‘what can little me do’.

However, I say you can make a difference. You will recall the butterfly effect, as expounded by Edward Lorenz, he of the chaos theory. He postulated that the effect of a beat of a butterfly’s wing in the tropics could trigger a hurricane many kilometres away.

I say to you, be that butterfly.

It is a sobering thought that you, we, are each utterly unique, an assembly of atoms never ever seen before. You will each therefore by definition, have abilities that are also unique. To make that ‘difference’ I speak of, you need to develop those abilities, and grow a fire in your belly, a determination to see things through.

Many of our gurus talk of the need to have ambition, but they are usually referring to the ambition to make money. While important, money does not equate satisfaction or contentment. Of its own, neither will it solve the problems you now face.

Nor will you achieve overnight success. It may take years, even decades. You’ll suffer setbacks, but that is in the nature of things, and our world needs stubborn battlers.

You will need to learn the skills of working with, rather than against, and of respecting the right of others to hold opinions that are so divergent from your own that they infuriate you. Anger is no solution. I think Churchill is credited with the saying ‘jaw-jaw is better than war-war’.

Seek friends, make alliances, and above all be positive. So often, even those who you originally felt were opponents, were actually just looking for solutions. Find those solutions.

Many years ago, a truth dawned on me. I had been used to complaining that ‘they’ should ‘do something’. ‘They’ frequently didn’t. I then realised that therefore ‘we’ must do something. Again, ‘we’ sometimes failed, and the clear conclusion was that ‘I’ must get stuck in. If I didn’t, why should someone else ?

Then something magical occurred. My actions suddenly activated the ‘we’, and in some cases, the ‘we’ became a reformed ‘they’. So I say, never be afraid to stick your head above the parapet.

Nor should you be put off by time. May I quote the proposed National Wetland Centre, at Lake Serpentine, south of Ohaupo. It is beginning to take shape, 16 years after planning started. Given maybe two more years, it could be completed.

And another issue took 67 meetings to end up with a solution that was welcomed by all parties. The Waikato Ecological Enhancement Trust was formed. It now puts hundreds of thousands of dollars annually into the wetlands and waters of the Waikato Catchment.

Stick at it !

To date, you have been absorbing, assembling, knowledge. Today, from this moment, your role changes. You have been learners, now, while still seekers, you become teachers. You have been followers, now you must become leaders.

Your collective tasks are frightening in their necessity. I challenge you. Get out there. Don’t be afraid. Be determined. Make sure our planet earth continues to be a place of diversity and beauty we can all truly love and protect. Play your part.

Then, when you reach the age of 80, people will say,’ yes, you made a difference’.

I end with a quote from the inspirational Helen Keller: deaf and blind from early childhood.

I am only one, but still I am one.

 

I cannot do everything, but still I can do something.

I will not refuse to do something I can do.

 

Thank you.

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.

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!

 

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

 

attack of the zombie snails Alison Campbell Mar 25

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Honestly, sometimes I think the zombie apocalypse is already here. Certainly zombies seem to be flavour of the month (& whatever friends say, I still can’t bring myself to watch Walking Dead). And I’ve written about them myself: well, the insect variety, anyway.

But our developing understanding of how parasites ‘zombify’ their hosts has been developing since well before the latest iteration of human zombies grabbed the popular imagination. I was reminded of this when I saw the video below (in all its over-the-top hyperbolic glory), for I was first introduced to the concept of zombie snails years & years ago by one of David Attenborough’s TV programs**. (According to my aging memory, it would have been an episode of Life on Earth.)

The parasite involved here is a flatworm (strictly speaking, a member of the branch of Platyhelminthes known as flukes) called Leucochloridium paradoxum. It has the delightful common name “green-banded broodsac”, which is a pretty accurate description of its appearance.

Flukes have a fairly complicated life cycle involving multiple hosts and L,paradoxum is no exception: eggs hatch into miracidia, and each miracidium subequently develops into a sporocyst. Each sporocyst contains large numbers of cercariae, which is where the ‘broodsac’ name comes from. In this state they move through the snail’s body to its ocular tentacles, where their bright colours & movement show through the thin skin of the eyestalks. Apparently, if you’re a bird, this looks like a caterpillar… Anyway, once ingested by a bird, the cercariae mature into adults, which reproduce and the whole cycle begins once more.

Where does the mind control part come in? Well, your average snail doesn’t usually spend a lot of time out in the open – such behaviour can make one rather too visible to predators. But instead of their normal photophobic behaviour, infected snails come out in the open, often climbing up grass stems or out onto branches. Combined with the flashy tentacular display – which doesn’t occur in the dark – this makes them easily visible, & easy prey. (Having said that, I do wonder whether this is truly mind control: after all, having a parasite stuffed up your eyestalk must impair one’s ability to detect ambient light intensity.)

 

** And in ‘reading’ up for this post, I see that the wonderful Sir David also covered the zombie ants:

 

"the aviator" – a vision of the future that’s a little too close for comfort Alison Campbell Jan 09

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I found the Herald’s front page this morning a sad and depressing read. My heart goes out to all those affected in some way by the terrible bush fires ravaging so much of Tasmania, Victoria, & New South Wales.

I also had a certain sense of deja vu as I read of the fires – for I’d read something similar last year, in blog-buddy Gareth’s book The Aviator, Book One of the Burning World series. Except that in the book, the scale of events is much greater than is (thankfully) the case at the moment, and Melbourne is destroyed by a fire storm. Gareth’s vision of a not-too-distant future in which our global ecosystems have been irreparably affected by anthropogenic greenhouse warming, is both an alarming foretaste of how things could become**, and a rather good read (another blogging friend, Ken Perrott, reviewed the book very favourably when it first came out, & I’ve been meaning to write my own review for quite a while). The story follows the key character (& narrator – well, one of them), an airship pilot called Lemmy, in his travels around a world in which ecosystems and societies have collapsed, or changed – in many instances, beyond recognition. (There are actually 2 narrators: the second is Jenny, the artificial intelligence who actually runs the airship. Their commentaries alternate, & it’s interesting to see the differences in perspective, especially given that the AI is to some degree self-aware.)

As the series title suggests, in this future world it’s not only Australia that suffers from fire. Lemmy also witnesses huge fires in the Arctic, where massive methane deposits originally locked under the ocean in the form of methane clathrates have been ignited and the flames burn seemingly endlessly. I’ve recently read more about these deposits in Bill McGuire’s Waking the Giant: we are talking significant carbon stores here, at around 2000 billion tonnes of carbon trapped in the form of clathrates: something that is highly attractive to energy companies & of deep concern to climate scientists.

The first time I read The Aviator, I thought it would be a rather good classroom resource for senior students. And that hasn’t changed on a subsequent re-reading. Its engaging focus on a current, extremely relevant topic means that the book could be used in many different areas as the basis of discussion and to provoke further student research: how do individuals, and societies, cope with change? What happens when the technologies we rely on so heavily are no longer available, or are concentrated in the hands of relatively few people? How would a rise in average global temperature affect various ecosystems? Is a future such as the one Gareth describes, something that we can yet avoid?

Highly recommended.

 

Gareth Renowden (2012) The Aviator (The Burning World). Limestone Hills Ltd.

Bill McGuire (2012) Waking the Giant: how a changing climate triggers earthquakes, tsunamis, and volcanoes. Oxford University Press. ISBN 978-0-19-959226-5

 

** In some ways it reminds me of Richard Cowper’s The Twilight of Briareus - though having said that, Cowper’s world has been sunk into an ice age, and his story has a strong mystical feel to it. But the themes of societal and ecological break-down, and how people cope with these, are common to both books.

 

 

 

 

moss s*x and springtails Alison Campbell Jul 22

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Sexual reproduction in flowering plants is often mediated by the birds & the bees (& other animal agents), but up until now the life cycle has appeared much simpler in plants like the mosses. Until fairly recently it was generally accepted that moss sex was a case of ‘just add water’: this released sperm from the male plants which could then swim in the film of water to where the female plants held their eggs. Of necessity this would mean that sperm dispersal could be only over quite short distances, of a few centimetres at most.

However, Todd Rosensteil and his colleagues (2012) decided to confirm the hypothesis that arthropods known as springtails could be involved in transferring sperm between male and female mosses. (Springtails and mosses evolved at the same time, during the Ordovician period.) They posed a number of questions: were springtails really acting as go-betweens in moss sex? If the answer was ‘yes’, how did the moss plants attract their little helpers? And, were the springtails important only if there was not much water around?

Using a common – & cosmopolitan – moss called Ceratodon purpureus, Rosenstiel and his colleagues first determined that female C.purpureus plants emit a significantly greater number of volatile organic chemicals (VOCs), which could act as signals to springtails, than male mosses do. They then carried out a number of experiments.

First of all, they gave springtails a choice between male and female moss plants – the tiny arthropods were much more likely to go for the female plants. (However, it’s not yet clear why the springtails respond positively to this signal: do they get some sort of a food reward?) The same was true when the springtails were given no visual cues & were simply offered a choice between male and female moss VOC samples.

Then, they set up a series of ‘microcosms’ – miniature ecosystems containing moss plants, and where the presence of water and springtails could be manipulated. This time the research team used both C.purpureus and another moss species, Bryum argenteum, in which earlier work had shown that springtails were implicated in spreading sperm around. Some of their microcosms had only the mosses. Others were sprayed with water but had no springtails, or had springtails but no water spray. And some had both springtails and water. The results were fascinating.

When a female moss plant’s egg is fertilised, the resultant zygote grows into a thin brown stalk with a capsule of spores on top: this structure is called a sporophyte. Unsurprisingly, mosses in the absence of both water and springtails produced very few sporophytes indeed. Both the ‘springtail treatment’ and spraying the mosses with water caused a marked increase in fertilisation, as measured by the number of sporophytes produced. But combining springtails and the water treatment saw the number of sporophytes more than double, compared to each treatment on its own. The researchers commented that

[t]hese results highlight the substantial role of microarthropods in facilitating fertilisation in mosses, presumably through enhanced sperm transport.

So maybe we really are looking at something akin to the relationship between flowering plants and their pollinators. And, given the potential antiquity of this arrangement,

it is important to consider the potential role that a plant-pollinator-like relationship may have had in shaping the evolutionary ecology of moss mating systems.

I will definitely be changing the ‘additional reading’ list for my first-years!

 

T.N.Rosenstiel, E.E.Shortlidge, A.N.Melnychenko, J.F.Pankow & S.M. Eppley (2012) Sex-specific volatile compounts influence microarthropod-mediated fertilisation of moss. Nature published on-line 18 July 2012, doi: 10.1038/nature11330

singapore’s stupendous supertrees Alison Campbell Jul 16

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I’ve just got back from the 2011 International Biology Olympiad. Our team did well – Richard Chou received a silver medal; Sumin Yoon & Evelyn Qian won bronzes, & Eddie McTaggart was awarded a Certificate of Merit. So well done, all round!

It was a testing time for our students, who were competing against the best senior school biology students in the world. Mind you, it wasn’t exactly a holiday for the jury members accompanying them, who put in some extremely long hours as the demanding practical and theory exams were finalised. But both students and jury members had time for relaxation on their schedules. In one of those ‘off-duty’ periods, along with 3 colleagues I caught first a bus & then a train to visit Singapore’s spectacular new Gardens by the Bay. Around every corner was a new ‘oh, wow!’ moment, and we collectively took an album full of photos. Like this one:

  singapore supertrees.jpg

These are some of the ‘supertrees’ – a grove of metal and concrete ‘trees’ betwen 30 & 50m high that dominate the park’s skyline (& put on a fine show at night, when they contribute to the light show along the downtown waterfront). They’re living gardens, clothed in vertical gardens & with a sky-walk running among them. At the top of each ‘tree’ is a bank of solar panels, harvesting sunlight to power the park’s systems; they also include a system to collect and distribute rainwater, & in addition act as exhaust and cooling systems for the huge domed conservatories nearby.

singapore supertrees & dome.jpg

There are two such domes: one houses a collection of gardens from different regions – including a 1,000 years-old olive tree. This & all the other mature (& adolescent) trees in the gardens were brought in from around the world (at goodness knows what expense!) The other is home to an artificial ‘mountain’ that provides a cloud forest environment to an enormous number of different plant species and includes a plunging 30m waterfall. It also provides some wonderful views, including another perspective on the supertrees that to me only serves to emphasise their other-worldliness:

singapore supertrees from dome.jpg

a follow-up (from a new blog) Alison Campbell Nov 30

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Over on ‘of trees and birds and other things’ Jarrod points out why it’s not a terribly good idea to base your view of a scientific issue on a single story in the popular press… (& hat-tip to David Winter on the atavism, who alerted me to this new evolutionary blog!) For the teachers & students who read my blog: Jarrod has an interest in forest ecology & his research area is evolutionary ecology, so I think it will be well worth dropping over to his place from time to time :-)

PS apologies for the original ‘dud’ link – all fixed now :-)

you could probably sell anything with the right sales pitch Alison Campbell Nov 06

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My post about zeolite & the supposedly ‘chemical-free’ nature of various dietary supplements containing the stuff led to some interesting comments, & generated a few ‘I wonder if…’ moments. After all, as Krebiozen said (in the comments thread to that post):  With the right sales pitch you could probably persuade some people that eating feline ‘tootsie rolls’ is good for them. They are 100% natural after all!

And goodness knows, if people will eat kitty litter itself (some brands are basically just zeolite) for its supposed health benefits **, he might just have a point. After all, how much of a step is it from coffee beans that have been through the gut of a civet to some of the other organic (see, that’s a Good word) materials emanating from the back end of a feline? As Herr Doktor said, there’s probably quite a bit of nutrients there, given that cats (being carnivores) have a relatively short gut & a reasonably rapid transit time (you will find perhaps more than you wanted to know about cats, their guts, & the products of said guts here): once ingested, food may reach the large intestine within 8 hours, although it may take well over a day to move on out from that point. (This was determined by giving cats capsules containing radioactive markers – after first emptying the colon using a series of enemas. Cats have an alarming array of sharp pointy bits – I would not care to try administering one enema, let along a series of them!)

Of course, much of the mass of faeces is actually bacteria: around 50%, in humans. So you’d want to scrub them out of the ‘tootsie rolls’, somehow. At first I thought you’d also need to remove the eggs from tapeworms and roundworms that would also be present in cat poo. But on second thoughts – why would you? After all, in newspapers from the early 1900s, you could find ads for diet pills containing tapeworm eggs (& there’s various urban myths around that may be based on this). And I was gobsmacked to find at least one website offering ‘diet pills’ that supposedly contain these eggs. (Whether they do or not is open to question.)

As for the roundworms… Well, any infection with a significant number of roundworms is going to leave you feeling rather the worse for wear. But an intriguing study from the University of Singapore suggests that a protein produced by a species of roundworm may possibly reduce the strength of allergic reactions. The impetus for this study was the observation that there seem to be fewer allergies in populations with a high burden of roundworms, something that’s also discussed in Robb Dunn’s entertaining book The Wild Life of Our Bodies: predators, parasites and partners that shape who we are today (2011, Harper Collins).

So, there’s our marketing ploy: all-natural, organic (& therefore ‘chemical-free’), & not only an excellent nutrient supplement but also a slimming aid & something that ‘supports your immune system.’ What’s not to like?

Except… if I can think of it, you can pretty much guarantee that somewhere, someone else will have beaten me to it. (As, indeed, the ads for tapeworm-egg diet pills demonstrate.) And also, imagination is one thing, & humour is good, but if you consider yourself a good, ethical person – & I do – then you’ll never go any further down that road.

** As Herr Doktor Bimler found out (see his first comment), at least one site selling ‘liquid zeolite’ promotes it as a means of removing teh ebil aluminium from your body. One suspects the person or persons making this claim are not chemists – for zeolite is an alumino-silicate mineral, & consuming the stuff is more likely to add to your overall aluminium load than it is to reduce it! (I would prefer to think that the sellers are ignorant of chemistry, as the alternative is that they know damn well what it is & don’t particularly care.)

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