biology | Scientopia Guests' Blog

What Makes a Cell Alive? and a joke

Oct 26 2011 Published by kevinmccarthy under Uncategorized

OK, last post about this, I kinda promise. I was thinking about this and reading Luisi's book and he asked another interesting question... one that reflects part of the discussion yesterday. If you survive all the way to the end, then you will be rewarded with my favorite (and only) Halloween joke... just to show I can do stuff besides ask pointless question.

Let's put aside the question about the difference between an apple and its tree and whether a dead thing has live cells and get to the fundamentals.

Take the nucleus out of an oocyte, as in the cloning experiments, is the nucleus living? And is the cell, without a nucleus, alive?

Now we get even more fundamental. The cell itself. Can it be alive without some parts? If so, which parts? Venter and his colleagues made a cell with scratch assembled DNA. There have also been various attempts to make a minimum cell by removing pieces until the cell no longer functions. I don't think this tells us very much about what it takes to be alive though. Even a minimal cell has all the functions that we normally think of a required for life.

On the other hand, we know that to continue living, a cell must have correct DNA. Venter's team missed a single nucleotide and the entire organism died. It must have been a critical function for life.

I think that a lesson we could take from this example is that life has to have instructions. It there has to be some underlying component that can tell a living thing how to do all the things that it needs to do. Again, we often think of a living thing as reproducing, metabolizing, responding, moving, and growing and developing. So the cell has to have the instructions to do all those things.

But leads me to a very unsatisfying definition of life. "The ability to do all the things that living things have to do." A better circular argument hasn't been seen, I think. But, I think we're on a good track. What is the purpose of life? If you go with the selfish gene concept, then the purpose of life is to spam the environment with as many copies of yourself as you can. What do all the copies have in common? The genes, the genetic information to create copies of itself and the ability to keep itself alive to make those copies.

Could we define life as “the existence of genetic information (enough to operate and reproduce the organism) AND the ability to maintain and/or propagate that information”?

That one sentence, after all of ten seconds reflection, really does a nice job of summing up the functions of life and still allows room for the existence of forms of life other than organic systems (e.g. computer based life or non-organic based life).

Since the horse, as a unit, cannot maintain or propagate the genetic information it contains, it is no longer alive. Same with the apple (which is still problematic to me). For a while, the dead organisms can use internal resources to maintain, but not propagate the genetic information. But it cannot continue the process for longer than the cells have resources.

A bacterium, on the other hand, does have genetic information and can maintain and propagate that information.

The cell without a nucleus is an interesting question, even with this definition. But a little thinking about my definition might reveal a new concept (one that human scientists don’t seem to like dealing with).

Alive may not be an all-or-nothing state. It may even be reversible in some situations. Perhaps the cell, without a nucleus, is dead. But by putting a new nucleus in, then the cell can become alive again.

Thoughts?

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A vampire bat returned to its cave. It was covered in blood.

The other bats crowded around it. "Where'd you get the blood?" "Look at all the blood." "Comon, don't hold out, where's the blood from?"

Finally, tired of the incessant whining of the other bats, he said, "Fine. Follow me."

All other bats followed him out of the cave. The flew across the field. They flew over the river. Finally, they flew into the forest and landed on a tree.

The other bats were so excited. "Are we there yet?" they cried.

"Almost. You see that big tree right over there, the really tall one?"

"Oh yes," they all replied.

"I didn't!"

10 responses so far

Why Are Dead Things Dead?

Oct 25 2011 Published by kevinmccarthy under Uncategorized

Here's another brain twister for the day. I was kind of hoping for a particular response to yesterday's "Are Apples Alive?" post and I got it this morning (thanks Arthur).

Now, I'm not trying to be difficult I promise, but if an apple that is in the fruit bowl (we'll assume recently picked) is considered to be alive... then why is an animal considered to be dead, when many of its cells are still functioning after we declare it 'dead'?

Our organs can survive for a fairly prolonged time in the event of the whole body death. Limbs can survive as long as 6 hours. Bone and ligament, much longer. Hair and fingernails continue to grow after death. The brain can survive for about 10 minutes under optimum conditions without major damage. There is at least one case of a cat being completely revived after one hour of death.*

Now, I freely admit that we're moving beyond scope a bit. We're talking about brain death and clinical death here and the prior conversations have been about living things. But I think that this serves to emphasize a point that I made earlier. Biology is squishy. It is very difficult to objectively and completely define some parts of biological systems, because there are always exceptions and, thanks to 3 billion years of evolution, life is very, very tough. To paraphrase Neil Stevenson, "We come from a long line of stupendous bad-asses... because every living thing in the history of the Earth that wasn't a stupendous bad-ass died quickly."

OK, let's get back to where we were... when considering a multi-celled organism, can we say that it is alive if all of its cells are alive as Arthur suggests? Yes, of course, the cells in the apple are alive, but is that enough to be considered alive? If it is, then why is our animal dead, when the majority of its cells are alive and will continue to be so for quite a while?

The direction I'm taking here, is that an apple fallen from the tree is not that different from a limb that has been severed from the body. That part, whatever it is, can survive for a time, but it is no longer connected to the super-structure that makes the entire thing alive. A living thing can reproduce itself in its entirety, a broken off portion probably cannot (let's not get into Planaria right now). A living thing can intake material and energy, which is then used for maintenance, movement, response to the environment. A broken off part cannot (again, in general, plant cuttings may work fine**).

BTW: In case you are wondering, I'm totally off my planned material at this point and thinking 'outloud'.

Can we say (should we say) that a multicellular organism is no more than it's component parts? Or is a multicellular organism something like what we were previously talking about... is there something that makes it more than the parts. Is there an emergent property that says we shouldn't treat single-celled and multi-celled organisms in the way (with respect to being defined as 'alive')?

But research seems to indicate that there is little difference between single-celled organisms and multi-celled organisms at some level of evolution. This report basically describes the change from single-cell to multi-celled due to predation. (for for the Springerlink link, I thought I had the full article downloaded, but I've lost it). So, again, life is squishy. There's not a dividing line between single-cell and multi-celled, so it will be (probably) futile to discuss a difference between life and non-life from that angle (and thus we see an example of real science in which we take a shot and it didn't quite work how we intended).

Or do we go back to the multi-celled structure having specialized cells and all the parts can't function unless they are connected (however tenuously) to the other parts. The whole organism can do all the functions of life, but pieces cannot. The cells in my reproductive system, while vitally important to the whole and the species, just can't do their job without the lowly small intestine.

I very well may be obsessing about this too much and am being silly. I don't think so, but what do I know. I think this is very important thing to consider. Not because we'll change the definition of life and biologists will stop studying prions or something silly like that. I don't want biologists and computer scientists to get into turf wars over who gets to study some digital organisms and not others.

I do think, that at some point, probably in the near future, some scientists will go for it. They will endeavor to create life in a large, complex simulation. Maybe it will be a giant Uery-Miller set-up with clary substrates all over and pyrite chunks for catalyzing, put a wave machine in to create vesicles on the clay. Will it work? We won't know until someone tries.

But, if we aren't sure what life is, how will we know if they succeeded?

OK, I'll go away now, I'm just blathering. The plan is to talk a little bit more about this concept of what is live, then get into some abiogensis research and see some of the really cool stuff that is being done to examine the questions of what is life and how did it get here?

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* Hossmann KA et al., KA; Sato, K (1970). "Recovery of Neuronal Function after Prolonged Cerebral Ischemia". Science (American Association for the Advancement of Science) 168 (3929): 375–6. doi:10.1126/science.168.3929.375. PMID 4908037.

Hossmann KA et al., KA; Schmidt-Kastner, R; Grosse Ophoff, B (1987). "Recovery of integrative central nervous function after one hour global cerebro-circulatory arrest in normothermic cat". Journal of the Neurological Sciences (Elsevier) 77 (2–3): 305–20.

** Which brings up the whole issue of stem cells.

7 responses so far

Are Apples Alive?

Oct 25 2011 Published by kevinmccarthy under Uncategorized

Here's where we get to some interesting questions on what is life.

Chapter 2 - Question 3

Is an apple – hanging on a tree – living? When it falls to the ground – is it still living?

This isn't a silly question

Wow, now we get to the meat of it. And this is where I start to have fuzzy thoughts on the subject. It all depends on how you define ‘life’. If reproduction is a requirement for life, then the cell in the apple are probably alive, but the apple itself is not. The seeds are the result of reproduction in the parent tree, not in the apple it self.

This article relates an interesting story about that.

What is the definition of life? I remember a conference of the scientific elite that sought to answer that question. Is an enzyme alive? Is a virus alive? Is a cell alive? After many hours of launching promising balloons that defined life in a sentence, followed by equally conclusive punctures of these balloons, a solution seemed at hand: “The ability to reproduce—that is the essential characteristic of life,” said one statesman of science. Everyone nodded in agreement that the essential of a life was the ability to reproduce, until one small voice was heard. “Then one rabbit is dead. Two rabbits—a male and female—are alive but either one alone is dead.” At that point, we all became convinced that although everyone knows what life is there is no simple definition of life.

To use the classic definition of life that I was taught many, many moons ago. Life has these characters: Composed of cells, has metabolism, grows, adapts, responds to stimuli, reproduces, and maintains homeostasis.

I kind of like that definition, but an apple is not alive by this definition. The cells within it are, but the apple itself does not grow, reproduce, respond (except chemically), or has a metabolism.

Can we separate the living thing from the cells it is composed of? i.e. if the cells reproduce, does the organism? If the cells retain metabolism, does the organism?

I ask because a dead organism may have most of its cells function even after the organism itself dies… at least for a little while.

Which brings us to another question, that maybe we should consider first.

Chapter 2 - question 1

Do you believe in the utility attempting to give a definition of life?

I do think that there is utility in dealing with this question now. Avida organisms can already evolve complex logic functions. And computers are beginning to approach the computing power of the brain (cat brains first) and the human brains processing abilities. (I will note that there is some skepticism on whether IBM has actually reached the equivalent computing power of a feline.) With that in mind, the question of what is alive will become very important… or maybe not. Humans have an unfortunate tendency to use resources and organisms regardless of the ethical considerations involved.

Life is like porn (you knew I was going there right?). We might not be able to define it, but we know it when we see it... or do we. Avida organisms are something that's pretty close to any reasonable definition of life, but they are definitely not made of cells. Could there be other non-cellular life that we would just ignore because we don't see cells?

So what are the qualities that life must have to be considered life?

Honestly, I've been thinking about this for several months (in those 12 seconds between when I can finally lay down and when I actually go to sleep... otherwise known as 'spare time'). It is extraordinarily difficult to develop a definition of life that does not have some exception. The apple above for example. Combinations are even trickier.

I have placed an additional burden in that I think that digital organisms could eventually be alive.

10 responses so far

Determinism, Cotingency, and the Accident of Mankind

Oct 24 2011 Published by kevinmccarthy under Uncategorized

Well, we seem to be off to a good start. I do have work tomorrow, so I'll just get this in now and let everyone stew over it all day. The best sauce and all that...

Since we already kind of got started in this direction, I'll put in questions 2 and 3 from The Emergence of Life - Chapter 1. This link is to my review of chapter 1. Here's a link to the book on Amazon (I get no income from this). But at the least you'll understand the thinking behind determinism and contingency. [NOTE: You'll find I link to Wikipedia a lot. It's a convenient location for much of the material that I think you might benefit from. I do not consider it an authoritative source, but the references and further reading are often peer-reviewed works that will describe material in detail, with authority.]

Chapter 1 - Question 2:

Do you accept the idea that biological evolution is mostly shaped by contingency? If not, what would you add to this picture?

First we need to talk about contingency and determinism. In the book, Luisi describes determinism (in this context) as the notion that life can develop purely by the interaction of chemical and physical processes. In other words, if the chemicals are available, life will develop. The opposite of this thought is NOT that there was an intelligent designer or something like that.

The other position is that of contingency. That is, the interaction of many factors (the majority of which may be deterministic) is required in an unlikely sequence of events to result in life. Contingency is something like chance, but not quite. Luisi describes it as this way. Contingency is getting hit on the head with a piece of tile roof. The deterministic factors (your walk to work, the poor condition of the roof, wind, gravity, etc) all combined to result in you getting hit with a piece of tile. Another way to look at it is what I call the “re-do” effect. If you reset everything back to the way it was before you walked to work, would you still get hit with the tile? If we reset the universe back 6 billion years and let it run again, would be in exactly the same place we are now?

In my mind contingency is the philosophical equivalent of chaos theory.

Now to answer the actual question. Is biological evolution mostly shaped by contingency?

First, this is a rather curious statement considering the focus of the book. Evolution really doesn’t have that much to do with abiogenesis… or does it. It can be shown that evolution occurs with any system that replicates imperfectly. Is a single RNA strand alive? If not, then we do have evolution on non-life and that evolution may drive replicators toward life. However, is evolution contingent anyway? I think so, if only because of the massive amount of potential influences on an organism. Mutations, environmental effects, what actually determines relative fitness, etc are all contingent things. A particular mutation might be great in an ice age, but if it's not an ice age, then it may be useless.

As far as abiogenesis is concerned, before reading this, I was squarely in the deterministic camp. However, contingency makes a lot of sense. It would explain why we haven’t heard from aliens (of course, there are lots of other reasons for that too).

At this point, I’m thinking that life is probably pretty common in the universe. However, I’m wondering how much life exists beyond slime molds (or alien equivalents)? Is multi-cellularity much more difficult to achieve than we might think? With a sample size of 1, it’s difficult to really examine this, but research seems to indicate that being multi-celled is useful and so may be likely once cellular organisms exist.

Intelligence may be less likely than multi-cellular organisms, but again, a small sample size has resulted in little ability to explore.

I can see the value in both positions. I think the future research that will be done in space exploration may well give us evidence one way or another. If the deterministic proposal is correct, then we should see a universe filled with life in all kinds of strange environments (more on this later). If contingency is more correct, then we should rarely see life and even more rarely see intelligent life. Which neatly segues into the third question...

Chapter 1 - Question 3:

Are you at peace with the idea that mankind might not have existed; and with the idea that we may be alone in the universe?

65 million years ago, dinosaurs were satisfied. They had existed on this planet for over 160 million years (almost a 1000 times longer than modern humans have existed). Mammals existed for much of that time, but they were rarely much larger than mice.

It took a freak accident to allow the rise of mammals, which has resulted in the development of modern humans. Without an asteroid crashing into and utterly devastating the planet, we would not be here. I have no problem with that.

I’m not so sure about ‘alone’. In the sense that humans may be unique as the only sentient species (i.e. capable of ad hominem arguments and recognizing the fact), I can live with it. I’ve read too much science fiction to be comfortable with the idea… I want to believe. But I can live with the idea that we are unique. That doesn't imply special privilege or a designer or anthropocentrism in my book. It just means we are lucky.

But in the sense that there are other living things, I don’t think I can be OK with that. I believe that there is too much energy in the universe (in the physics sense) and the likelihood of complex chemical reactions is too great to say with any confidence that Earth is the only planet with life. Since we find organic compounds in the most unlikely of places (nebula and comets) I think that life is not only possible, but likely to exist elsewhere in the universe, perhaps even elsewhere in the solar system. This life, like the dinosaurs may be satisfied at whatever level it has obtained to this point, but I doubt it. Life changes. Darwin and hundreds of years of observation have shown us that life changes and in ways we cannot imagine (reptiles developing a proto-uterus for example).

Again, this is my belief, but if life exists elsewhere in the universe, then intelligence also exists in the universe.

Your thoughts?

4 responses so far

Who is This Guy and Why is He Here?

Oct 23 2011 Published by kevinmccarthy under Uncategorized

Hi. I’m very excited to be guest blogging here. This is my first guest blogging spot, so please be gentle.

Cassandra’s Tears is where I normally hang out blogging. I attempt to make some really cool science accessible to the non-scientist. I also talk a bit about technology and the anti-science positions. Rarely, readers are treated to a bit of humor or a past attempts at short stories and poetry.

I have always enjoyed science. When I was three, I could shock anyone older than about 30 by telling them I wanted to be a paleontologist and name dozens of dinosaur genera. Over time (more than I’d care to actually think about), I learned a lot about myself.

I still love science, but I love the knowing. I’m not real big into the actual finding out. Basically, I suck at experiment and observation. I’m also easily distracted. I can’t stand to be fixed onto one subject. I’ve never gotten an advanced degree, because they don’t make advanced degrees in general science. Still, I’ve learned a lot on my own and am pretty comfortable with most areas of science.

This stood me in good stead while I was teaching. I taught, for a few years, at a tiny little school in Sabine Pass, Texas. You might remember it being run over by hurricanes Rita and Ike. I joined Sabine Pass School right after Rita and stayed until right after Ike. I taught; biology, chemistry, physics, IPC (physical science), oceanography, and TAKS prep courses… all in the same year. Suffice to say that I know a little about a lot.

I’m a huge fan of science fiction, even though there is little out there worth reading or watching nowadays.

Now, I’m still involved with both education and science. I’m a science content specialist for a company that works in publishing, education, and assessment. So, I get to read all the cool stuff and then try to incorporate that into our products. Yes, I live in a cube farm.

On Cassandra’s Tears, I’m engaged in a chapter review of The Emergence of Life by Pier Luigi Luisi. Abiogenesis is a fascinating topic and so much has been learned in just the last decade. What’s interesting about the book is that the author has included some chapter ending questions for the reader. These aren’t like ‘test’ questions, they are thinking questions.

Those are what I would like to talk about here. I think this would be a good place for discussion. I’m planning on taking a few of the questions about life and the generation thereof and giving you my thoughts about the matter. I would love to hear your thoughts on the matter as well.

“What is life?” and “Where did life come from?” are not simple subjects. I think it’s the nature of biology (being squishy rather than firmly defined).

If you think about chemistry, you can firmly declare a molecule to be of a given type. It isn’t water unless it’s 1 oxygen and 2 hydrogens in a covalently bound system. You can even talk about solutions with varying ratios of solute to water, but you can define them in very specific ways and have a standardized convention for stating how much solute, how much solvent, and the concentration of the solution. So, even if there’s a range, you still have a very specific definition.

You can't really do that for life and there are a lot of 'ifs', 'ands' and/or 'buts' involved.

So, that's what we'll discuss here. Totally new, totally fresh, so let's get the ball rolling. What do you think a good definition of life is?

7 responses so far

Evolving Ideas and Intelligent Design

Feb 19 2011 Published by paolo under Uncategorized

Well, it seems that my earlier post on Darwin has ruffled some feathers in the Intelligent Design (ID) camp, so they've been trolling the comments section on my personal blog. This post started out as a response, but I decided to expand it to include some of the context surrounding Darwin's work.

A comment by VMartin

...One wonders why no one noticed “natural selection” before. And there were ingenous minds in the history! One answer might be this – it was never observed because it doesn’t exist. Darwin implanted this speculation there. And “On the origin of species” reads sometimes like comedy. One should try to count how many times Darwin used words like “which seems to me extremely perplexing” etc....

It's interesting how 'simple' natural mechanisms and systems can take longer to be acknowledged than one might have thought. Heliocentrism is another example of something that now seems very obvious, but was historically slow to be recognised (and is still not recognised or not known about by some). It's easy to blame organised religion for the suppression of such observational truths about the universe, since challenges to traditional belief were seen as heresy and dealt with accordingly, but there's far more to it than that.

One reason why some scientific theories have been slow to come to light

One reason why some scientific theories may have been slow to come to light

Let's set the scene - Darwin's formative years were tumultuous with regard to sociopolitical events. The Napoleonic wars drew to an end with the Battle of Waterloo when Darwin was six years old, the Peterloo Massacre occurred and the Six Acts were drawn up by the Tories to suppress radical reformers when he was ten - reflecting the ongoing social division between the establishment and the public.

Peterloo Massacre

When Darwin was in his twenties the power of the strongly traditional British establishment finally began to wane, when the Whigs came to government allowing the 1832 Reform Act and the 1833 Slavery Abolition Act to be passed. There was also the devastating Great Famine in Ireland when Darwin was in his thirties and all of this was set against a background of the Industrial Revolution, which was providing the impetus for science to play an increasingly important role in society.

This meant that Darwin's work was by no means formulated in intellectual isolation. Theories of evolution had been proposed 2,400 years previously, but they were poorly developed. Natural philosophers like Darwin's own grandfather Erasmus and Jean-Baptiste Lamarck raised the issue of evolution at around the time of Darwin's birth, but the mechanisms for evolution were either ignored or flawed. Evolution was an established topic of discussion and publication by the time Charles Darwin came onto the scene, with people like Robert Grant being more radical on the subject than Darwin found palatable in his early manhood. Despite this interest, the mechanism of evolution remained elusive - perhaps unsurprisingly, since the academic community addressing natural sciences was largely composed of members of the clergy and the natural theology of the time was seen as being mechanism enough.

But a literature base that was to inspire non-traditional hypotheses was also developing at the time - Vestiges of the Natural History of Creation in particular offered an alternative view that was seen as too radical by many - clearing a path for subsequent works that challenged orthodox views. Given this context, it is perhaps unsurprising that Darwin and Alfred Russell Wallace converged on the same premise at the same time. In short, the ideas evolved to fit the intellectual and social environment. The same has been true of other discoveries and inventions where there was a requirement for the right intellectual groundwork to be laid in advance. This groundwork is required before a robust theory can take root - and Natural Selection is a component of the robust theory of Descent with Modification, or evolution.

The critiques I have seen of evolutionary theory have come from people who quite clearly don't understand it - and such critiques tend to rely on statements of incredulity rather than a strong factual base. No well-supported alternative hypotheses have been constructed or presented and a lack of understanding hardly counts as a robust refutation of a well supported theory.

An accusation by IDers is that 'Darwinists' (N.B. I don't know anyone who would call themselves a Darwinists following the New Synthesis) stick with Natural Selection because they are atheist. I think I see the real agenda emerging here, particularly when you see evolution as a theory being conflated with just one of the mechanisms involved. After all, Natural Selection is not the only mechanism involved in evolutionary adaptation and speciation - there are also other factors like hybridisation, horizontal gene transfer, genetic drift, perhaps some epigenetic influences and artefacts of EvoDevo processes. But these factors are still constrained by the simple fact that if they are selected against, they will not be perpetuated.

The Intelligent Design agenda

John A. Davison left this comment on a previous post:

Natural selection is a powerful force in nature. It has but one function which is to prevent change. That is why every chickadee looks like every other chickadee and sounds like every other chickadee – chickadee-dee- dee, chickadee-dee-dee. Sooner or later natural selection has always failed leading to the extinction of nearly all early forms of life. They were replaced by other more prefected forms over the millions of years that creative evolution ws in progress...

First and foremost, the suggestion that Natural Selection prevents change is erroneous - change will occur if there is a change in the environment and/or if beneficial mutations arise in a population (tell me that mutations don't happen - I dare you...). The obvious response to the next statement is that I can think of six different 'chickadee' species, with an additional three subspecies (and this is ignoring numerous other very similar members of the Paridae), all are similar, but all are different - so the statement makes no sense as it stands. Getting to the meat of what is being implied about the Creationist interpretation of species, another bird provides a good example to the contrary. The Greenish Warbler shows a distinct pattern of hybridising subspecies across their vast range, until they form reproductively isolated species at the extreme ends of their range, where they happen to overlap yet not hybridise (a classic ring species [pdf of Greenish Warbler paper]). This is a well-known example of how genetic variation can accrue and give rise to new species without any supernatural intercession.

Salamander ring species

Another comment by VMartin

...But no wonder that Darwin considered “natural selection” for such a complicated force. Even nowadays Dawkins speculates that NS operates on genes, whereas E.O.Wilson has brushed up “group selection” recently (citing of course Darwin as debeatur est .

So may we “uncredulous” ask on which level “natural selection” operates?

As to this question about the level on which Natural Selection operates, I thought the answer was pretty obvious - it operates at every level. Change the focus of Natural Selection from passing on genes to the only alternative outcome - the inability to pass on genes. It doesn't really matter which level this occurs at or why - be it a reduction in reproductive success when not in a group, or a deleterious single point mutation - if it happens then Natural Selection can be said to have occurred. Being 'fit' simply means that an organism has not been selected against.

There's a lot more to modern evolutionary thought than Darwin's key early contribution, but Darwin is still respected because he was the first to provide a viable mechanism by which evolution is driven. This mechanism has helped make sense of an awful lot of observations that were previously unaccounted for and, moreover, evolution has been observed and documented on numerous occasions [here's a pdf summary of some good examples].

I fail to see why Intelligent Design has been taken seriously by some people - it relies on huge assumptions about supernatural interference (so it fails to be a science) and I have as yet never seen a single piece of evidence that actually supports ID claims. The only research I have seen mentioned by proponents of ID are old, cherry-picked studies that report a null result from an evolutionary study - this is not the same thing as support for ID, as anyone who can spot the logical fallacies of false dichotomy and Non sequitur (in particular the fallacy of denying a conjunct) will tell you.

I like to keep an open mind, but as soon as I see logical fallacies being wheeled out I lose interest in getting involved in the discussion. This may be a failing on my part, because I should probably challenge misinformation, but quite frankly I don't have the time or the patience - much as I hate to stoop to an ad hominem, my feelings on this are best summed up by the paraphrase:

when you argue with the ID lot, the best outcome you can hope for is to win an argument with the ID lot

and my time is far too precious to waste arguing with people who ignore the arguments of others and construct Straw man arguments based on cherry-picked and deliberately misrepresented information. I have no problem with other people believing in any of the numerous gods that are available, but please don't try to bring any god into science (and heaven-forbid the classroom) - since it is neither necessary nor appropriate.

Intelligent design as a scientific idea

54 responses so far

The rest of the iceberg

Feb 18 2011 Published by paolo under Uncategorized

Working in a museum is an awesome experience. It's something I wanted to do since the age of four and I've been incredibly fortunate to get established in this highly competitive field. The role of a curator is particularly rewarding since we get to research collections and bring some hidden treasures out into the light of day (figuratively speaking of course, our head of Conservation would be very disapproving if we did that literally).

Unfortunately, no matter how much material we manage to put on display, the vast majority of collections are kept in storage since there is simply too little room to display everything. This means that what you see in showcases is very much the tip of the iceberg; at the Horniman Museum for instance it is estimated that 95% of the collections are in storage. Of course some people are critical of this and want to see more material on display, whilst others subscribe to the less-is-more philosophy in exhibitions (see point 8 ), but being in storage doesn't mean that the collections don't get used - far from it. Researchers, artists and members of the public use the stored collections for all sorts of projects - in fact, we even refer to our stored objects as our study collections.

Exhibition space limitations aside, much of what we have in storage wouldn't be considered to be particularly interesting if it did go on display. Some specimens are very small and plenty are by no means pretty. Many can't tell an interesting story without an awful lot of additional information and prior knowledge. As a curator I have a desire (and indeed a duty) to provide some of the information and knowledge needed to make objects relevant and interesting. As a technophile I think that the Internet provides a fantastic medium for doing this, which is why I started a blog back in 2009. This has provided an opportunity to show a tiny glimpse of the rest of the iceberg.

Damage by the ivory-eating squirrel, the odd object in storage that inspired the first Friday mystery object

So for 83 weeks in a row I have posted an image of an object and I've asked a simple question relating to it (usually I ask for an identification). The responses to my question gives me an opportunity to gauge how self-explanatory an object is and it also provides an insight into how objects are perceived by a varied audience. Then when I provide an answer to my question the following Monday I get the chance to provide a greater depth of information.

This Friday I've decided to use a particularly challenging object, that a few people will identify immediately because it is so distinctive, but anyone who hasn't seen one before is likely to struggle a bit. Can you work out what type of bone this is and which species it comes from?

(N.B. this is the same bone photographed from different sides - click for bigger)

For those few that are in the know perhaps you could drop hints rather than blurting out the answer and I hope that everyone else will feel free to ask for clues or make a note of their thoughts about this specimen in the comments section below. Good luck!