Saturday, 31 July 2010

Sean Carroll and Ediacaran Reductionism

It is no secret that I am a fan of Sean B. Carroll, a prominent geneticist who often gets to voice his opinions on evolutionary theory. I mentioned him in a previous blog which was about the genetic changes involved in form and function, wherein Carroll's prediction was validated by the study. He is one of the main scientists at the forefront of evo-devo, investigating through genetics and embryology the relationship between genotype and phenotype. He often discusses the role of gene switches in the evolution of phenotypic change. His first book, Endless Forms Most Beautiful, looked at how gene expression produces form such as patterns and limbs and is one which I fully recommend to anyone wanting to get insight into this field. His second book, The Making of the Fittest, looks into the genetic evidence for evolution and also comes recommended, being better written than his first and containing some very interesting examples. I have not yet read his third book, so I can't comment on that one.

Recently, in the New York Times, Carroll published an article titled Translating Stories of Life Forms Etched in Stone  about the impact of the Ediacaran fossils. He chronicles the thought surrounding these fossils, starting with Darwin's dilemma of a lack of fossils before the Cambrian, through the discovery of the first Ediacaran fossils to modern views surrounding the fossils. There's some interesting information in the article, I particularly like the mention that Andrew Knoll likens the Ediacarans to a Rorschach test, as everyone interprets them differently. Reading through the article though and it seems Sean Carroll, who is not a palaeontologist (so I wonder why he wrote this article), favours the shoehorning interpretations of Gehling. The first clue can be seen in the image which accompanies the article:

This is a Pteridinium from Namibia, which looks bilateral in this image even though other fossils show that it is not and actually has a three lobed body. For example:
This choice of image puts the idea of bilateral forms in mind, the fossil doesn't actually look too unusual compared to some Ediacarans. Accompanying the article online is a slideshow with some incredible photos. The first is a small and beautiful Dickinsonia from the Ediacara Hills, chosen because it is mentioned in the article and maybe also because it looks superficially like many extant forms. Also from Australia is Spriggina, another which is iconic of the Ediacaran forms and is often thought to be related to modern forms (despite the difference in symmetry). Next is Archaeaspinus from the White Sea in Russia, a form which is often labelled as from the group proarticulata, a proposed phylum which also includes the two previous organisms. These are often linked with the chordates, an interpretation which would likely please Carroll.

Next in line on the slideshow is  Fractofusus from Mistaken Point in Newfoundland, a spindle-like fossil which would be difficult to shoehorn into modern groups. Kimberella comes next and was mentioned in the article, this one is from Russia. This fossil has often been considered to be a possible mollusc and potential radula marks have been found around the fossils. Following Kimberella is Charniodiscus, this one from Newfoundland and curiously the image is upside down. Charniodiscus is an interesting frond fossil which is sometimes linked to the sea pens. A favourite of mine follows, Parvancorina,  from Australia, a shield like fossil which can be tentatively linked to the trilobites. The final image is Yorgia from Russia and is often linked to the proarticulata. Anyway, back to the article.

The first hint of Sean Carroll's chosen interpretation comes subtly in the following sentence:

Dickinsonia, for example, has been interpreted as being a relative of jellyfish, a marine worm, a lichen, or even as a member of a completely extinct kingdom.

The concept of the Vendobionts is not an unpopular one as this phrasing might suggest. Carroll makes it sound like an extreme view. His view becomes more obvious soon enough, as he says, "But, in fact, such simple bodies are exactly what should be expected of primitive forerunners of later animals." He says this in relation to the lack of features which we use to identify extant phyla today and in that I agree with him, however, he must also ignore the features found in some Ediacaran forms which exclude them from known phyla. He also states that a few bilateral forms are known and gives Kimberella as an example, but it is not clear whether or not he takes into account that many display glide symmetry and not typical bilateral symmetry; Kimberella is one of the few which seems to actually be bilateral. 

Carroll then goes on to explain why these multicellular forms took so long to appear and does a good job, but then ends by saying, "Our earliest animal ancestor probably had no head, tail, or sexual organs, and lay immobile on the sea floor like a door mat." 

Overall the article is a good read and quite informative. It is odd that it is written by a geneticist and not a palaeontologist, but Carroll does not get things wrong, he simply puts his own slant on things, a slant which is shared by many palaeontologists. It would be interesting to see what a palaeontologist like Seilacher would think of the article. 

End of the Month - Time for some news.

It's that time where I feel I have not been educational enough, or haven't written enough, so I force myself to seek out interesting news, usually resulting in me raiding ScienceDaily and giving snippets of insight into what's going on in the science world. This time I have gone a little bit further and have found a wider range of stories, from other sites too. Some are up to date (ish) whereas the odd one might be a few weeks old. Ah well, here goes:

Segmentation Solved?
One of the most important innovations in evolutionary history was the evolution of segmentation, allowing for evolution to become more creative. Many segmented organisms have repeating segments which are identical (think of a centipede or millipede for example) and this allows evolution to co-opt these segments for other purposes, allowing differentiation whilst not disrupting the original function, as one segment continues its job whilst the other alters (this occurs at genetic levels with the duplication of genes and gene complexes too). Increases in differentiation lead to specialisation and the result is often a highly complex structure. Dawkins termed the evolution of segmentation a watershed event in evolution, opening up the door for incredible diversification (see The Ancestor's Tale for details). Organisms such as arthropods and annelid worms are obviously segmented, but so are we and the rest of the chordates. Our segmentation is slightly more obvious when we look at the vertebral column, though keep in mind that segments can fuse and merge together.

A question that has been looming in the minds of scientists is whether or not segmentation evolved once, in a common ancestor of the three aforementioned groups, or whether it is a convergent feature. The three groups are not closely related, so a segmented common ancestor would be back in the Precambrian, around 600 million years ago. If it evolved multiple times, then it may have appeared close to the Cambrian explosion, but then an explanation is needed in order to explain why it evolved in three separate lineages at the same time. A recent study looking at the genes involved in segmentation has found that they are remarkably similar in the separate segmented phyla, suggesting that we all did evolve from a segmented common ancestor and that segmentation evolved only once. See here for more details.

Necks: An Important Evolutionary Innovation
Interestingly the last item of news segues into this one quite nicely. Scientists have found that the evolution of necks, during the transition of our ancestors from sea to land, was a very important step in our evolution. The neurons controlling limbs were moved from the brain into the spinal column (fish still have them in their brains) separating the limbs from the head. This allowed for improved dexterity and coordination in our "fishibian" ancestors which eventually led to diverse limb forms such as those in birds, apes and whales. See here for more.

Stress and Lampreys
The lamprey is a jawless fish which attaches itself to its prey and sucks out their innards, causing havoc in some lakes. Trace our history back, past the fishibian (Tiktaalik roseae) in the last segment but not as far as the common ancestor in the segment before that and you will find that we descend from jawless fish and so share a common ancestor with lampreys. Evolutionary biologists look at relationships like this in order to work out how certain traits evolved as the differences can give great insight, especially when the other organisms have a "primitive" form of the trait being analysed. In this case the system being studied was the endocrine system, especially the production of stress hormones. Humans have more than 30 stress hormones and this study has shown that lampreys appear to have only one, giving insight into how our own, more complex system evolved. See here for more.

Belly Flopping Frogs
This story seems to be on every science site, but it is quite a good one so I thought I would mention it. A study in "primitive" frogs has shown that they evolved the ability to launch themselves through the air before they were able to land properly. The evolution of a proper landing, which came later, made them more efficient and less vulnerable, as anyone who has tried to catch them will know when they continuously hop away. This is a great story which also conjures up amusing images, so read here. It saddens me that frog diversity is really struggling right now, especially in a time when we are discovering some very interesting adaptations among them (who can forget the frog which walks on water; the Pinocchio-nosed  frog; the frogs which breathe through their skin; or the elaborate behavioural patterns of some frogs?) who knows what we will never discover?

Sex-y News
A bold new theory for the evolution of sex has been put forwards which looks deep into our prokaryotic past. How meiosis evolved has been baffling scientists for a long time. Meiosis is the process in which the genome is divided and recombined with that of another individual in order to produce offspring. It is generally believed to have evolved from mitosis, the process by which eukaryotes divide; their DNA is divided into two and goes off into two daughter cells. Researchers have now been looking into the reproductive processes in prokaryotes, binary fission and transformation. Binary fission has similarities with mitosis and is where a prokaryote splits its DNA strands to act as templates for two new strands which inhabit the daughter cells. Transformation on the other hand is where bacteria take a segment of DNA and insert it onto the genome of another cell where it recombines. The researchers have suggested that the process of transformation is the precursor to meiosis, not mitosis as most think.

The "basic machinery" for sex appears to have been present in eukaryotes from very early on, whereas the evolution of meiosis from mitosis would suggest a long period where there was no meiosis. The key to the problem appears to be stress; prokaryotes tend to favour transformation in conditions where stress is common and damage to DNA occurs. Similarly, in eukaryotes which reproduce by both mitosis and meiosis, such as yeast, stressful conditions tend to favour meiosis over mitosis. Both transformation and meiosis are utilised during stressful conditions as they combat DNA damage. The researchers have suggested that this gives great insight into how meiosis evolved from transformation. See here for more on this fascinating story.

Red Blood and More Lampreys
Studies have shown that red blood has evolved independently in both jawless fish (lampreys again, for example) and jawed vertebrates. Similar situations, in this case the need to get oxygen around bigger bodies, has resulted in the parallel (or is it convergent?) evolution of haemoglobin in these two lineages. The two groups co-opted completely different proteins for the same role. See here for more.

Smelling Whales
It has long been thought that all cetaceans, the order containing whales and dolphins, were devoid of a sense of smell. After all, toothed whales and dolphins lack many of the necessary features to achieve olfaction (sperm whales, killer whales and dolphins have been studied). The dissection of a bowhead whale brain found that they have enlarged olfactory systems, suggesting that they could possibly smell. Bowhead whales are baleen whales, so they may have kept their sense of smell in order to detect krill, they also have two blowholes, meaning they may have a directional sense of smell. Whale olfaction gives good insight into evolution as toothed whales cannot smell at all, yet descended from mammals which could. A look into their genomes shows that their olfactory receptor genes are there but not able to be used due to mutation. See here for more on the whale olfaction discovery and see here for my own previous discussion of whales and evolution.

Underwater Palaeontology?
Yes it's true, this segment is not going to mention evolution (except in mentioning that I am not mentioning evolution). It also looks at a recent underwater fossil find. Scuba divers searching an underwater cave found the bones of an extinct monkey in the Dominican Republic. The monkey fossil is relatively recent, but comparisons with older fossils is giving insight into, errrm, evolution (oops, sorry). This unusual find may give a lot of information on the divergence of monkeys and apes. See here for more on this story. Although it would likely be very difficult, the idea of underwater palaeontology is quite appealing as we normally look for fossils on land, even though most of the planet is underwater. It is almost as appealing as extra-terrestrial palaeontology, which is the subject of another post maybe...

New Species and Novel Fundraising
David Penney from the University of Manchester has discovered a new species of spider (the world's oldest) and a new species of lacewing encased in amber among others. He is offering people the opportunity to give these species scientific names, at a cost. He is accepting donations of £5,000 or more in order to name the species and raise money to fund his research. It is an excellent idea for fund raising and ordinarily I would hope that the names given would be good ones, but scientists are not always known for giving species insightful names and some get silly or playful (see Richard Fortey's book Dry Storeroom No. 1 for example, or look at the dinosaur Irritator). See here for some beautiful pictures of the fossils and here for the university's public article.

Ducks: More Obsessed With Penis Size Than We Are
Some species of duck compete with penis size in order to win mates. Instead of bulking up like many organisms do, experiments showed the ducks varying their penis size depending on how much competition there was. See here for the article. Also, with the mention of birds, check out this article about sex chromosomes in mammals and birds, it turns out we took opposite paths.

That's all for now, but not quite all I have to talk about. Some of the news I found was worthy of its own post, due later (or tomorrow). That's not to say that these others aren't as interesting, they simply caused less tangents.

Friday, 30 July 2010

Fishing - Jason Style

I waded out into the lake, determined to find the perfect spot to make the catch of a lifetime. My ageing rod was not the most hi-tech and flashy, but it was trustworthy and could take a battering. The cold winds were getting stronger, lashing at my face, as the rain began to pound against me like bullets against a brick wall. I persisted, my determination dragging me through the downpour as lightning pierced the sky and thunder proclaimed the fury of nature through the heavens. The black waters of the lake threatened to knock me down if I did not leave but I stood my ground, focussed on the movement beneath the surface. The dark shapes swam teasingly around the bait, nudging it tentatively as though they knew it was a trap, a sumptuous but deadly trap. My heart hammered the inside of my chest harder and faster than the rain as I watched a curious shape lunge at the bait. Instinct kicked in. I pulled back. The fish flew out of the water, struggling to get free. The ensuing wrestling match stretched into eternity before I got my prize catch safely back to shore and left the cacophonous storm. When I returned to the safety of having a roof over my head I was able to admire my catch and compare it to my previous trophies.

This is Diplomystus dentatus, an Eocene fish from the Green River formation in Wyoming, part of the Dean Lomax collection.

In this picture, where I look like a criminal having my prison photo taken, I am holding Lycoptera; Jurassic fish from the Liaoning Province in China, also from the Dean Lomax collection.

Finally, this is Thaumaturus intermedius, also Eocene, this time from the famous Messel Darmstadt, Germany and found in Dean's collection.

I'll never forget that day's fishing experience, it is the sort which can change one's life forever. Fishing is one of the oldest trades, allowing us to eat our distant cousins which stayed in the waters for thousands of years, thriving off of their flesh and eating it with chips. I wonder what these fish taste like.....

Wednesday, 28 July 2010

Has ScienceDaily failed me?

Like many people I have occasionally tried to get my head around some of the concepts in quantum mechanics, sure it hurts my head, but you don't half feel clever if it works. Heisenberg's uncertainty principle? No problem! Schroedinger's cat? Fed him earlier. Quantum entanglement? What?

Quantum entanglement is one of those concepts which makes my head spin -  the idea that two particles which were once connected can only be fully described if both particles are mentioned seems simple enough, but then things start getting trickier to grasp. As observable states are indeterminate until a measurement is made, quantum entanglement ensures that the two particles will correlate in what is being measured (as opposed to obeying simply probabilities such as a 50/50 chance when there are two options). Where things really get mind boggling is that this implies that when one particle is measured the state of the second is known, even if they are separated by unimaginable distances. This requires the effect of entanglement to occur faster than the speed of light. Crazy huh?

Whilst browsing ScienceDaily I noticed this article, titled Quantum Entanglement in Photosynthesis and Evolution. Naturally it piqued my interest; I wanted to know how quantum entanglement could apply to evolution, whilst also raising the possibility that connecting it to evolution would help me understand it better. The short article does not mention evolution anywhere. It is interesting enough on its own, but not what the title promised. Shame. I wanted to broaden my mind. Instead, I leave you with this amusing cartoon:

Monday, 26 July 2010

Creationist Palaeontologists?

At some point I plan on doing a blog post about Kurt Wise, a "creation scientist" who has a doctorate in palaeontology. Wise is not the only creationist to have qualifications in palaeontology, as I just found when looking at the Answers in Genesis list of creationist scientists which can be seen here. I'm not going to bother critiquing them properly, I am simply incredulous that there are so many when the fossil record practically screams evolution. I have found the following:

Dr Harold Coffin, listed on AiG as simply "Palaeontologist" but through a tiny bit of research I found mention of him in a Wikipedia article on polystrate fossils and there is an article on him at CreationWiki here. It seems he is a palaeobotanist.

Dr Arlton Murray, who is discussed in this AiG article where he says some pretty inane things about the fossil record (no transitional forms and all that nonsense). He seems to have mostly worked as a preparator on vertebrate fossils. He is one of those who claims to have accepted evolution before finding God. Shame.

Dr Gary Parker, listed as "Biologist, Cognate in Geology (Paleontology)" and a little bio can be seen here. I may some day have to review him in more detail, as some of his book titles include The Fossil Book and Dry Bones and Other Fossils. He is also one who apparently taught evolution before becoming a Christian.

Dr Joachim Scheven, listed as a palaeontologist, with a bio here. He seems to have specialised in insects in amber, so it did not surprise me to seem him connected to the claim that past organisms are the same as modern ones (of course, creationists cherry pick here). I also found this article by him which makes little sense on its own.

Dr John Whitmore, listed as a geologist and paleontologist, with a bio here. His biology PhD and his geology M.S. are both from Christian institutions which are clearly creationist. It seems he may have published in secular journals, though his publications seem to have nothing to do with creationism (they look at taphonomy and environmental indicators for example) a list can be seen here.

Dr Kurt Wise is listed, but I intend to discuss him at another point.

AiG also list a few palaeontologists who were around before the theory of evolution (or during its early days) and mention some as "old earth compromisers". They are John Woodward (1665-1728), John Hutchinson (1674-1737), Georges Cuvier (1769–1832 and an OEC) and Richard Owen (1804–1892 and OEC). There are also some which are since Darwin, including L. Merson Davies (1890–1960). 

There is also a man called Joe Taylor who runs a fossil business, who is written about here

Okay, so there weren't very many, but the amount there are is startling. I can't help but feel that many have swallowed the false dichotomy of God vs evolution and chosen the former over the latter without realising that one can have both. In future I will make a list of theistic evolutionist palaeontologists to sort of complement and counter this one at the same time (though mostly just for reference). 

Precambrian Dragons? For Real?

A few weeks ago I was linked to a page about a guy who claimed to have found Precambrian dragons. What was meant by this I did not know, I was thinking the term dragon might have been hyperbolic, but no, this man fanatically reports his finding of actual dragons. Here is the site I was shown, but sadly it looks like it will be removed and many of the images are not loading.
The above image shows what Hallett calls Terrybinski Seazoria

The Discovery

Back in November 2003 (nearly 8 years ago according to Hallett's calculations) in northern Utah, USA, Mike Hallett (1967~ ) made the greatest discovery of his life. Since then he has dedicated 14,000 hours to uncovering its secrets. Hallett claims to have found the remains of prehistoric sea dragons! These were the biggest, most advanced organisms to ever roam the planet and they have completely changed the face of science, according to Mike.

The implications of this are astonishing! According to Mike's website these finds show that the Precambrian contained a highly advanced marine ecosystem, with highly evolved animals which went extinct 540 million years ago.

The Animals

These things were enormous. In Mike's words, "The most striking example of working on a prehistoric Hallettestoneion Seazoria Dragon occurs when you are standing in the mouth surrounded by highly specialized, instruments of death, 3 foot long Seazoria Dragon teeth. Compare 30 inch Seazoria Dragon teeth with a much earlier 150 million year old Tyrannosaurus Rex with 8 or 10 inch teeth." Let's ignore for a second that Tyrannosaurus rex was not 150 million years old, clearly these "Hallettestoneion Seazoria Dragons" were enormous. Apparently they ranged from 100 to 300 feet and there were many species.

The Implications for Science

As Hallett likes to point out, they completely change our understanding of the history of life, palaeontologists are espousing an "obsolete and incomplete" view. According to Hallett this has kickstarted a new area of science called Hallettestoneology and apparently sits between geology and biology (I wonder what's wrong with palaeontology). The timeline of life has to be rewritten. Mike points out that the Cambrian starts right after a major cataclysm (or caticysum on one of his sites) but this is news to me. He also likes to discuss our current "obsolete" knowledge:

Alright lets [sic] address the very basis of your of your [sic] primary concern. How could we possibly have advanced marine life that [sic] older then [sic] your textbook says life could be. [sic] How closely have you looked at and examined the current fossil record that all paleontologists and other life sciences specialists adhere to so animatedly. [sic] 220 million years ago for the first land Dinosaurs [sic]. 267 million years first vertebrae [sic] backbone life. Science says that there is no advanced life beyond 220 Dinosaur and 267 million year barriers.

Well, I do enjoy looking closely at the fossil record and the claims of palaeontologists, what budding palaeontologist doesn't?  I have no idea why he thinks vertebrates only evolved 267 Ma ago, as they date back to the Cambrian explosion. He also says:

No scientist has ever even contenplated [sic] any type of advanced large scale life in the Precambrian time era ending 540 million years ago. Now science is beggening [sic] to understand that the precambrian era once thought to only have invertabrate [sic] life the size of a fingernail, actually contained the largest and most advanced forms of life.

Again, as anyone who reads my blog will know, invertebrate life before the Cambrian is not merely the size of a fingernail, as many of the Ediacaran forms are actually quite large. 

Zoria Repeats

If you take even a brief look at any of his sites you will find constant mention of something called a Zoria repeat. It is claimed that all the "teeth" found follow specific patterns, established whilst they grew. Apparently the "Zoria repeat shape is basicaly a five sided triangular wedge with an attatchment base at one end growing to a specialized reinforced tip at the other end." There are 117 repeating structures in the Zoria repeats. Below is my favourite image of the teeth, as they have managed to identify replacement teeth too:

I know what you're thinking, those are just rocks right? That's what I thought too. That's what I still think. Hallett claims that his research proves they are biological because they grew from the inside out (something he has not actually shown, he simply claims it). The sites claim that these are exact and follow consistent, inherent and predictable "mathimatical [sic]" equations. So, compare the following images of facial spikes:
Do you see how they match exactly and follow the exact same pattern? No? Really? Neither do I, they are clearly just rocks. 

Is Mike Hallett Alone on This?

Sadly he is not. Here are some of his colleagues:
He also likes to repeat the claim that he has consulted many experts and name drops a couple of geologists and palaeontologists here and there. This is true, he does seem to have consulted them. They have confirmed that the rocks in the area date to 540 Ma, but Hallett has not asked for any consultation on his purported fossil specimens. How odd, considering he is not an expert but yet he has access to the minds of scientists caught somewhere between geology and biology. Perhaps deep down he knows that they will likely laugh and say, "Mike, that's nothing but a rock". 


I cannot decide what the ideal word here would be. Lunacy? Madness? Insanity? Either way, this guy seems to be off his rocker, a certifiable wackaloon, but he hasn't half provided me with some entertainment. Check it out for yourself, there is a great description on his Seazoria Hub Page. There is also the HALLETTESTONEIAN SEAZORIA DRAGONS DISCOVERY ORGANIZATION Facebook page (with 18 fans nonetheless). You can also add Mike Hallett on Facebook if you want to know more. There is also the official Seazoria website.

Finally, I leave you with a video full of images of the "discovery":

The Future of Palaeontology - Kids of Course

Kids are the future, a phrase that none would disagree with I reckon, they are also at a great age to get interested in fossil hunting and palaeontology. Kids are one of the key target audiences for a museum, so it is not surprising that Doncaster Museum runs events for them to get involved with. On Saturday the theme was fossils and I was on hand to help fill their heads with wondrous information.

The day went very well, with lots of families turning up and taking part. They got to look around the displays, do activities, draw pictures, handle fossils and have fossils identified for them. When I turned up I was asked to man the tray of sand which had fossils hidden within, which the children had to find by brushing the sand away. I was put on the spot a bit, something which can be a very useful experience. I saw the fossils I had to talk about for the first time at the same time the first kid saw them, so I had to work out what they were and talk about them at the same time. The first couple of kids just wanted to find the fossils, not fussed about learning, but it picked up after that and I found that the children were listening to my supposed expertise. I tried to make my responses interesting for their parents too, as they proved to be very interested, offering up some very good questions, but also because they are a teacher of the child. The parent can go away and remind the child of things they forgot, but also whilst there they will be more aware of how the child learns, which the random palaeontologist they just met would not know.

Thankfully I knew vaguely what all the fossils were. Some were obvious, but some were tricky as well, which made things interesting when talking to the kids about them. Almost all of them recognised the ammonite fossil straight away, so I talked about what they looked like and how they grew (the chambers were visible on one side). Quite a few were able to recognise Gryphaea arcuata and of course it was quite easy to get a response when it was mentioned that they are also called "Devil's toenails".

There were a few plant fossils as well. Neuropteris actually had a label, but I knew nothing about it except that it was possibly a fern. The one on the left is not the museum specimen.

There was another fern which may have been either Pecopteris (left) or Dactylotheca  or something else. I honestly don't know with ferns.

The third plant fossil was the trickiest in my opinion. When I asked what they thought it was many thought it was a bit of horn. The fossil was actually a stem called Calamites, a type of horsetail. When I first looked at it I went as far as calling it a plant until I spotted some more Calamites on display.

There was also a belemnite, which was quite a tricky one for the kids, so it amazed them to hear that it was like a squid. The trickiest for me to explain was possibly the trilobite pygidium, which by the end I think I was describing as "the back end of a woodlouse-like creature found in the sea before dinosaurs". Ah well, I love trilobites, but they are quite awkward to explain.

The most difficult fossil was only identified by one kid who seemed to really know his fossils. It was a chunk of crinoidal limestone made up completely of the stems of crinoids. I found it amusing to keep people guessing (I liked the comparison to macaroni) only to see them looking just as perplexed when I announced that it was a crinoid. I then found myself explaining what a crinoid was, along with a few facts about them, which usually involved me waving my arms above my head as though I was a crinoid myself.

Whilst manning my post I was sat next to Pete who was doing the fossil handling, so when things were slow for me I would occasionally interject with titbits of information. I also had a couple of people show me fossils to be identified, one of which really surprised me. I was expecting an ammonite when the girl passed me a little nodule, only to find a rather nice trilobite. I told them that I reckoned it was about 400 million years old, before Dean identified it as a Diacalymene from Morocco.  

The day went very well, so hopefully everyone learnt something, or even a lot of things, I know I did. I only had one little, almost microscopic, blip. We were chatting away, answering the questions of one lady who was there with her granddaughter, when she said, "Isn't it strange that Christians still don't believe any of this?". I was a bit taken aback, especially considering the first geologists were actually creationists who began to realise just how old the Earth was. I did try to point out that the curious phenomenon of denying science is a relatively modern occurrence based mostly in America but I don't know if it sunk in, she was bombarded with all sorts of information about fossils at the time.

Ah well, it was a great experience which I will hopefully repeat again and see just how much I can manage when put on the spot with fossils again. I do hope that we may have planted seeds of wonder and awe in their minds, potentially influencing a future palaeontologist. Who knows?

None of the photos here are of the museum specimens, I took no photographs. 

Did you know that I know Dean Lomax?

I've mentioned Dean a couple of times, the first time back in April when I mentioned the Palaeocritti site for the first time. For a bit more on Dean see here. I mention him here now as he was recently on the radio, which you can listen to here, his part being around the 35th minute onward.

In the interview you will hear him talk about what it is like to try to make your way in the world as an autodidactic palaeontologist who has not taken the academic route. You'll also hear him mention Doncaster Museum and Art Gallery, which allows me to segue into my next point.

So how do I know Dean? Well, I actually came to know him because of the blog I did mentioning Palaeocritti. Dean found it and contacted me, so we got chatting about palaeontology and I mentioned wanting to volunteer at Donny museum. Thanks to Dean I am now doing that and work alongside him, drooling over fossils, helping out where we can (which will be the subject of my next post). The eagle eyed readers among you will have noticed that I mentioned both Dean and the museum in a previous post recently.

After he had done the interview the feedback seemed to be very positive and one lady even called in to say that the BBC should give him his own show. Check it out here, 22 minutes in. It is quite tempting to phone in and proclaim "I second that" though I would add that I want to see him in a dinosaur costume. If he gets famous just remember, you heard about him here first (unless you are actually Dean reading this, as I know he does, in which case, hi Dean).

Sunday, 25 July 2010

Dickinsonia and Spinther: A Frustrating Comparison

The Ediacaran genus Dickinsonia is an iconic form which still eludes identification. In its time it has been identified as a Vendobiont, a placozoan, a cnidarian polyp, a coral, a sea anemone,  a polychaete worm, a turbellarian, a mushroom, a xenophyophoran protist, a lichen and even a close relative of chordates.

When viewed as a polychaete worm, an interpretation which is now seen as lacking support (merely being an attempt to shoehorn), it was compared to the genus Spinther. Clarkson, in Invertebrate Palaeontology and Evolution (4th ed.) writes:

A close resemblance to the modern segmented worm Spinther, which lives on and eats sponges, has been noted, so Dickinsonia  has been considered to be an annelid. It differs from Spinther  only in that the distal claws (parapodia) situated on the ends of the segments and used for crawling are lacking. 

My frustration came when I tried to search for an image of Spinther purely out of curiosity. Below is the only image I could find:

I can see why it is compared to Spinther, but the resemblance is superficial even without a proper image. Below is a good quality image of Dickinsonia for comparison:
I would love to some day go through all the different interpretations of Dickinsonia, especially as there are so many, but when it was so difficult to find an image of Spinther  I am not sure it will be worthwhile. For the record, I go with Vendobiont. 

An interesting comparison

Earlier whilst searching for a quote on Christianity by the late Sir Ronald Fisher (evolutionary biologist) I found out that he used to make quite an interesting comparison. He compared the whole "works vs faith" debate with "Darwinism vs Lamarckism". In the "works vs faith" debate the idea is that either faith is the only way to salvation or works can help you achieve it (in other words salvation can be achieved through being good). The similarity of the "works" view to Lamarckism is that both require the effort of the organism; in Lamarckism a change in one's lifetime, often through things like stretching (as with the giraffe's neck example), is what drives evolution. Lamarckism is obsolete and has been since Fisher showed it to be so (among others, though it should be noticed that epigenetics has some Lamarckist qualities). Similarly, works alone is not considered to be a tenable theological view with regards to salvation. Some see it as faith alone, but others will stress that faith must produce works or it is dead. I'm not sure what the correlation here would be. Perhaps it is the claim that we are products of natural selection and that we can break free from it and should do so? Or maybe we could point out that evolution by natural selection is an incomplete understanding without epigenetics? Either way, it seems to be nothing more than an interesting thought experiment, a superficial comparison which is interesting but has no bearing on how we properly interpret each phenomenon.

Saturday, 24 July 2010

Fossil Collecting: Fun, but not always fruitful.

Within the last couple of weeks I have had a couple of fossil collecting trips which have varied a lot. Both were enjoyable but couldn't be more different. One involved lots of people of a wide range of ages; the other was just myself and a friend. The first involved me searching through shale for fossils on a beach; the other had me looking at a limestone/dolomite cliff risking being nettled.

Runswick Bay - 15/07/2010

The first trip, on the 15th of July, was organised by Doncaster Museum and led by Dean Lomax of Palaeocritti. There were around 40 of us altogether, ranging from young children to the elderly. We went by coach to Runswick Bay, a well known fossil collecting locality north of Whitby, as can be seen on the map below.

It is not a place I had been before, though I knew the rocks would be of Jurassic age. There is also the potential for finding some quite random fossils, brought down to the bay by glacial erratics, but it is often best to stick to the shale in order to know what time period your collected fossil is from. We arrived at the bay in the morning to find that coaches could not get down the hill, forcing us to walk down a steep hill, so of course it rained on us. One thing I did find interesting on the trip down the hill was the paving slabs in the driveway of a house; they contained pseudofossils formed when magnesium oxide gets into cracks in limestone.The picture below shows a view of the bay:
When we were collecting fossils the weather cleared up. Some of the children started finding fossils straight away, their eyes seemed almost unnaturally attuned to spotting fossils. Rocks were repeatedly overturned, shale smashed and everyone went along at their own pace. It was one of those trips where everyone found fossils. It was very easy to come across casts of ammonites and bivalves, devil's toenails (Gryphaea) were common, along with occasional belemnites. One of the best finds was an ammonite mass mortality (Harpoceras I believe) and also a potential crustacean part (I reckon a crab) and some possible fish bones. I was also a little jealous when Dean found a chunk of rock with ripple marks; I do like ripples (and really should get the picture of me at Durdle Door next to some huge, uplifted ripples). Below is a picture of the group fossil hunting, you can see me on the left with my shorts, typical hat and big boots:
My own finds were nothing special (though all fossils are special in their own way) but then I really went just for the enjoyment of it. I have some ammonite casts, lots of bivalves (I always find bivalves) and a couple of belemnites.

South Elmsall - 20/07/2010

My trip to South Elmsall quarry was very different. South Elmsall is to the north of Doncaster towards Wakefield and happens to be just down the road from where a couple of friends of mine live. Whilst researching the geology of the area I found out that there might be fossils in South Elmsall Quarry from a paper I found online. From what I gathered from the paper, there was the possibility of finding more like those I have found in Conisbrough, plus a few others not found here. My friends who live near South Elmsall had asked me to come help them with some stuff, so I mentioned the possibility of me heading to the quarry at some point, to which they responded by saying I could take their youngest son out with me as he has just finished GCSEs and doesn't have a lot to do. So on the Tuesday we set out for about an hour to explore, with this map to guide us:

It was actually very easy to find and thankfully a lot of the cliff was exposed; a previous search on Google Maps made it look like the trip would be futile. The first thing you see when you approach the cliff are some excellent examples of stromatolitic domes. Formed by algae building up sediment, these domes resemble a lettuce in cross section. I did not have a camera with me, so sadly I could not take pictures, but here is an image from the paper:

This image is not particularly good, or at least it does not compare to how I remember them. There is no sense of scale (we are always told to make sure there is something to reference for scale at uni) and the typical graffiti at the bottom could be any size really. The stromatolites are worth looking at, so at some point I will go back and take some proper pictures. I looked around as much of the rocks as possible and found no fossils at all. No Liebea squamosa, no Dielasma elongatum. The paper had me thinking I would find many bivalves (Liebea, Bakevellia, Permophorus and Schizodus) along with bryozoa (Acanthocladia) but I should have been realistic, after all, many of these are meant to be in Conisbrough too but I have not yet found them. I did, however, find some casts which appear to have been Bakevellia binneyi as they were roughly the right size and shape, plus there were more than one of them. There was nothing I could take home with me, only the image of stromatolites and bivalve casts in my head. I intend to return, at least to take pictures, but I may also find something.

These two trips make an interesting contrast. The first had me finding things easily, coming away with a heavier bag even though I had emptied it of my lunch. The second had me coming back empty handed, which I don't mind too much as it is good experience; palaeontologists have to get used to disappointment as many of the best finds seem to be down to luck. In my opinion, going out and failing to find something to take home is more worthwhile than not going at all.

Thursday, 22 July 2010

The Garden of Ediacara: Book Review

I just finished reading Mark McMenamin's book The Garden of Ediacara: Discovering the First Complex Life and figured it might be interesting to review it. Initially I planned on doing a little review, after all, it is on one of my favourite subjects and had the potential to be a favourite of mine. Instead I found that I wanted to write about it in more detail. The book was published in 1998 so I am a long way behind in reviewing it. I will not criticise it in light of more recent information, as that is unfair when science advances so much (except where predictions are concerned) so I will largely critique the book as though it were brand new.

McMenamin gets off to a decent start in his first chapter, titled Mystery Fossil. The chapter seems to follow a chronological order, though he is found switching from topic to topic: where his interest in Ediacarans comes from; the origin of life; symbiogenesis; the Cambrian explosion; and more. There are a couple of hints at where the rest of the book might be heading as he emphasises the endosymbiotic views of Margulis and it is clear in retrospect that McMenamin fancies himself as a big ideas sort of guy. This is not a fault, but it does run the risk of becoming self-indulgent. His Hypersea theory gets a brief mention, something which I know little about and this book oddly enough did not properly discuss it. Ah well, on to the Ediacaran forms.

The second chapter, The Sand Menagerie, had me enthralled. McMenamin races through numerous different Ediacaran fossils from medusoids, to Tribachidium, to frond fossils, to Erniettids, to Rangea, to Dickinsonia, to Spriggina, to sponges, through Ausia, Corumbella, Inaria and Arkarua. If you are interested in Ediacaran forms, then this book may be worthwhile even if you only read this chapter. Sometimes when reading popular science the reader just wants to be shown things and told what they are with no need for rhetoric with the aim to persuade. This chapter succeeds in presenting the fossil forms, along with some very useful images (which may have been embellished a tad) without seeming to assert the author's strong views.

Chapter 3 continues the good form. Vermiforma gives insight into the work of an palaeontologist, particularly one interested in the enigmatic Ediacaran (a phrase which somebody should trademark; interestingly it is never used by McMenanim in this book, to my recollection). The author starts by showing and discussing his field sketches, something all palaeontologists do, and gives an idea of the sort of work involved. The chapter does a great job at showing how difficult fossil interpretation can be and how dramatically they can change, particularly for Ediacaran fossils. This is precisely what I like to see in books on palaeontology, an insight into the techniques used and how human interpretation is.

The previous chapters ranged from 10 to 36 pages, just what one would expect and I would not have minded if some of them had gone on for longer. Then chapter 4 came along, sitting pretty at 60 pages. I've already used the phrase "self-indulgent" in this review, but that is the perfect way to describe the chapter entitled The Nama Group. McMenamin goes overboard, quoting large chunks of his notebook which seems to contain descriptions of every little thing he sees. Hot dog stands, plants on display, birds flying. I'm not even completely sure what he was doing the whole time. It was tedious. Immensely. Frustratingly the colour plates are largely from this section, showing images which look like holiday photos rather than showing the fossils which you likely wish to see if you bought the book.

If you wade through his waffling, you will find tidbits of information dotted around. There are also some chunks which are very interesting but which are drowned out by the rest of the text. Twenty two pages in and there is a worthwhile discussion of Seilacher's views on Pteridinium (Seilacher features a lot in this book, both in descriptions of events and of interpretations, rightly so). One of the highlights of this chapter, if you pay attention, is the hit and miss attempts at trying to make a cast of a slab of Pteridinium fossils, another insight into professional palaeontology, but one you would be forgiven for missing. On pages 86 and 87 (twenty six and twenty seven pages in to the chapter) is a good little discussion between Seilacher, Gehling, Runnegar and McMenamin, all big names in the world of Ediacaran palaeontology but with some very different views. Despite having waded through the first half of the chapter, I would have been happy if this discussion had gone on longer. The next thirty pages of chapter 4 sees more irrelevant description littered with occasionally useful nuggets of information and then a little discussion between Seilacher and Pflug (another big name).

The fourth chapter had left a bitter taste in my mouth, I had grown weary of McMenamin, perhaps made worse because I was really enjoying the book before that. If I wanted to read a poorly written travel journal I would have looked for one away from the palaeontology section. If you decide to read the book for yourself it might be an idea to skip chapter four; I get the feeling that I might have enjoyed the book more without it.

Chapter five, titled Back to the Garden, discusses one of the main themes of the book, as the name suggests. It looks into McMenamin's "Garden of Ediacara" hypothesis which posits that many of the Ediacaran forms were symbiotic organisms feeding through both osmotrophy (absorbing nutrients from the water) and different variations of autotrophy through unicellular symbionts (some may have used photosynthesising bacteria or protists, others may have adopted chemosynthesising bacteria). It also suggests that things were peaceful in the "Garden" with very little predation. McMenamin makes quite a compelling case, addressing many of the criticisms aimed at his hypothesis. I found it to be a very interesting and plausible view, but as Richard Fortey had pointed out, it is not really falsifiable (McMenamin pretty much waves this criticism away). This chapter is a good example of the theoretical side of palaeontology, with the bonus of a description of an experiment carried out to test some of the views, showing the experimental side of the science. This chapter appears to be a return to form, however, there is the unsettling hint that McMenamin may begin indulging himself in a different way.

Cloudina is the title of the sixth chapter, one which seems to pass by with little incidence. I hate to say this, but I don't remember much about it. There is mention about the possibility of predators in the Precambrian and a little about the rapid evolution of eyes, but this chapter really does just seem like filler and I can't put my finger on why. Shame really, I like Cloudina. 

The transient feeling of the last chapter may be partly due to chapter seven, Ophrydium, which is also short but packs in information about colonial protists which shed light on the plausibility of the author's "Garden of Ediacara" hypothesis. This was another section which McMenamin could have expanded upon but did not, it would have been interesting to say the least.

Reading chapter eight was no surprise, McMenamin had named the Precambrian supercontinent Rodinia and was naturally going to talk about it. I do find palaeo-geography interesting, it is invaluable knowledge for palaeontologists and much of the information comes from studies into ancient organisms. The problem is, when it is discussed in popular science books it is very difficult to follow what is going on. The placement of the continents is very visual, yet popular treatments are distinctly lacking in images. Even Fortey's descriptions in Trilobite suffered from this problem. This may be a personal issue, perhaps I am simply rubbish with descriptions of continents. This chapter was interesting though and McMenamin's surprise at the accuracy of some claims of The Urantia Book is worthwhile reading.

By chapter nine things had gotten more interesting again. The author goes back to a more anecdotal style, though this time it can be forgiven as it gives yet more good insight into palaeontology. He describes repeated failure to find fossils, along with the problems of finding funding, only to then make a big find due to a sequence of serendipitous events. This sort of narrative is common when talking to palaeontologists; scientific knowledge and skill are balanced with luck and patience. McMenamin also gives good examples of how the press can completely mess up when reporting on science. My only issue with this chapter came right at the end, when the author proposes a rule which he unsurprisingly calls "McMenamin's Rule" which states to "[always] make scientific rivalries work to the benefit of science". Although I agree with him, after hearing about his Hypersea theory, Garden of Ediacara hypothesis and his naming of Rodinia, I couldn't help but think that he is either desperate to be heard or was showing off in a sense. I also couldn't help but feel that I may have thought differently if he had excised the unnecessarily large fourth chapter.

Chapter ten puts an end to the return to form. Titled The Lost World, it starts with a couple of quotes, just as the other chapters did, however, they seem irrelevant to the chapter which follows. One is a statement from Richard Fortey, pretty much a paraphrase of the previous criticism from Fortey which was left largely unaddressed. The second quote is one from McMenamin and his wife, only the second chapter to start this way and there are three altogether; perhaps he took George Bernard Shaw seriously when he quipped "I often quote myself. It adds spice to my conversation." The chapter discusses what to name the period at the end of the Precambrian, something which is important but just felt like McMenamin wanted to have his say on every little topic tied to the Ediacaran (he proposes it should be called the Lipalian in honour of Charles Walcott who discovered the Burgess Shale).

It may not be surprising that I approached chapter eleven, A Family Tree, with some trepidation. I expected McMenamin to propose that he simply knew the solution. I wasn't far wrong, but I was very pleasantly surprised with this chapter. McMenamin briefly discusses some of the views concerning the classification of Ediacaran forms, then puts forward his own revelatory hypothesis of the development of Ediacaran forms which gives a natural way to classify them. He gives an illustrated description of these forms starting as cell families  and developing through iterations. Vary the number of cell families, the number of iterations and their directions, and you end up with a wide possible diversity of forms, many of which are found in the Ediacaran. Under this view, the Ediacaran forms are not quite multicellular, they are metacellular, and diverged from all other animals before the development of the blastula. Intriguing stuff.

I said before that McMenamin fancies himself as a big thinker. Chapter twelve, Awareness of Ediacara, sees him thinking in ways for which the appropriate adjective is not "big". Put simply, he believes that what he calls cephalo-Ediacarans were on an evolutionary path to intelligence, an example he goes on to consistently cite as convergent evolution. This chapter was ill placed, it seemed to pop out of nowhere and lacks the necessary support that such a wild claim needs. The next chapter could have done with going before it, but that would have changed little.

Chapter thirteen, Revenge of the Mole Rats, is about convergent evolution. McMenamin sits in the Simon Conway Morris camp which asserts that convergence and constraint are so ubiquitous that the evolution of intelligence is inevitable. Much of McMenamin's chapter reads like Conway Morris' work, with examples of iterative evolution and talk of teleology found throughout. He addresses the views of Pierre Teilhard de Chardin, whom he seems to respect a lot, despite the usual negative views towards him. His own religious views are never made clear, but he is certainly sympathetic towards Teilhard's Omega Point  concept and accepts a view of static teleology in nature. Interestingly this reminded me of Stephen Jay Gould's research into the Piltdown conspiracy as he concluded that Teilhard was the culprit. It had me wondering if Gould was following the evidence or whether his desire to eradicate the spectre of teleology led to him wanting to discredit one of its main supporters. Teilhard had publicly debated George Gaylord Simpson, a mentor of Gould's, on this very subject, and Gould has written at length about the lack of direction he sees in evolution.  McMenamin sits at the opposite end of the spectrum to Gould and this chapter encapsulates his arguments on the topic; worth reading if you are already interested in this.

McMenamin ends his book with an epilogue about parallel evolution, one which seems pretty pointless, much like large chunks of this book. Overall I would recommend it if you are interested in Ediacaran forms as there are so few books which discuss them. I would also recommend it if you like to hear strong views about palaeontological interpretation and the bigger questions of evolution. The book shows that McMenamin sees himself as a big thinker, but that he lets his wild ideas get the better of him at times. This can be useful, as it means other scientists will scramble to get rid of any nonsense and will uncover new information as the boundaries are pushed.

Thursday, 15 July 2010

Tricky Shots at Brimham Golf Course

The cast:

Handy Andy Pandy Man, a real life Handy Andy Pandy Man. He is handy at fixing things. He is Andy at fixing things. And he is capable of complete Pandy-monium. He is also a man. A very married man. Soon to be dad. Awwww.

Jess the dog, the brains of the operation. Expert climber, runner, jumper, trouser, sniffer and barker. Jess is female, but don't let that fool you, she is one of the guys. Except that she is also a dog.

Owen, certainly the youngest member of the group; certainly the deadliest. He is trained in mixed martial arts and has an ice cream cone for a nose. He showed the world how it was done that day, creating a legacy which will never be matched. He hasn't even reached ten yet.

Rob, a man who, contrary to his name, will not rob you at all, except if you happen to be a beautiful young maiden in which case he will rob you of your innocence.

Mr Stevie T, the other brains behind the operation. Don't let the clothes fool you, he does have a girlfriend, a lovely girlfriend at that. But this was a day for men only (and Jess) so he had to dress himself.

Jason, aka Jesus, seen here in a rare hatless moment. He supposedly has some geological training, which is apparently useful in places with rocks.

This formidable team of motley men descended on Brimham rocks with only one thing in mind: victory. The rocks at Brimham were laid down in Carboniferous river deposits and eroded by glaciers in the last ice age. It also happens to be one of the world's most challenging golf courses. Spread around the teetering rock formations, in amongst the beautiful cross bedding, are many holes often believed to be impossible. Our boys laugh in the face of impossible. They once said counting to infinity was impossible, until Owen did it in his sleep. They said it was impossible to divide by zero, until Jess did it with her eyes closed. They even said it was impossible for Jason to grow a beard!

Before they started their assault on the infamous golf course, the lads made sandwiches the real way - they cut cheese with a card! Extreme golf must be played on a full stomach. We don't know why. We don't care why. We just like to eat sandwiches with card-cut cheese!

Steve got the ball rolling, or rather, he got the ball flying, flying over more trees than you can imagine, followed by some more trees. The course starts off with an easy shot, lulling you into a false sense of security.

As can be seen here, Owen's skill was unrivalled, we had to up the stakes! Enter Rob, the human golf tee:

Things got intense for Steve early on, when he walked right into the path of Owen's back swing. But Steve took it like a man! A man with no testicles, so I suppose he didn't take it like a man. He carried on is what I am meaning to say.
Pandy was the first to go for one of the infamous tricky shots, hitting it from the tree with such aplomb! "Such aplomb" is the name of Pandy's favourite golf club.
Mid way through the golf game, as we were making good time, we stopped for a break. How do real men take a break? We play Frisbee in precarious places, that's how! (On an extra note, look at that lovely bedding at the bottom left.)

Back to golf and Pandy got a little stuck when he landed a hole in one. The problem was that it was the wrong hole.
Steve then had to show us all how to do it properly, whilst we all watched in awe.
Little did he know that Owen had this little gem up his sleeve. How he fit this whole rock up his sleeve I don't know, but that shot was impeccable, sublime, perfect and just a little awe inspiring. 
Not one to stay in the shadows of others, Rob developed an unorthodox technique which saw him sinking the balls like German U-boats in a minefield (an underwater minefield, like in that game Minesweeper). 
The game did not end there, for there is more to come I just do not have the photographic evidence yet. So I leave you with this cliffhanger: