Thursday, January 31, 2008
In fact, there are at least three species of native mammals - but they are excluded in the above narrative - bats, seals and sealions.
taking a long step back, New Zealand was once part of the great southern land, Gondwana, finally separating around 85 million years ago (see Wikipedia and University of Waikato) - the former indicates New Zealand separated specifically from the Antarctic land mass before Australia did; however, it's not clear whether Australia was at the time counted as Antarctica. It seems to me most likely that Australia was its last port of call, since the coastlines match so neatly.
In 2006, a mouse-sized mammalian fossil 16 to 19 million years old was discovered in New Zealand's St Bathans fossil bed, in the south of the South Island. This has been written up in PNAS (Proceedings of the National Academy of Sciences [of the USA], available here. Interestingly, in the paper it is said to be "nontherian". That is, it split from the mammal lineage before marsupials: therians are defined as non-egglaying mammals: thus this one (the 'SB mammal') would be defined as an egglayer.
Colin Tudge's 2000 book The Variety of Life details the metatherians (marsupials) and eutherians (so-called placentals), then mentions eight groups of nontherians, of which only the monotremes (Australia's platypus and echidna) survive; of the others, only multituberculates and morganucodonts are mentioned. Wikipedia has an entry on Prototherians (aka non-therians), but Tudge doesn't recognise this as a clade, only as a small-p colloquial term for a non-therian mammal. Wikipedia adds to the group Triconodonta and Docodonta; as you can see, the classifications are mainly based on tooth characteristics. Why? Tudge: "Most of the extinct lineages are known only from a few teeth and jaws" - prescient, as this is also the case for the SB mammal, with the addition of a bit of hip. (Braincase is also mentioned as a differentiating characteristic.) I've seen no word on the placement of this creature within non-therians (Wikipedia's entry says the SB mammal is not a monotreme) - probably not an easy task, and the discovery's only about a year old.
I remain curious, too, about the other three of Tudge's non-therian clades; however, Tudge constantly reminds us that at this level of taxonomy, judgment calls are inevitably involved.
Eutherians ('placentals') and marsupials split 100 to 125 million years ago; this specimen dates from 16 to 19 million years (see the entry in New Scientist), suggesting this creature survived for at least 100 million years. Notably, this is the first land mammal fossil found in New Zealand.
The ubiquitous Mike Archer, current UNSW Science Dean, was involved in this study. He suggests it goes against the conventional wisdom that New Zealand temporarily disappeared below the water from 25 to 30 million years ago [due to some combination of rising oceans and/or erosion] after separation from Gondwana, and re-emerged due to its location on the boundary of two techtonic plates pushing against each other. Archer reckons it was too small to succeed at rafting [so it must have remained indigenous since before the split; others disagree.
So, did New Zealand stay above water, or did the SB mammal raft?
I'm currently reading Richard Dawkins' The Ancestor's Tale (2004, Phoenix, London), and he is a great believer in the ability of rafting to explain movements. In a nutshell, rafting is the drift of land-based animals on floating vegetation masses, typically due to the effects of storms. Dawkins (p150) details a large-scale eyewitness event (iguanas in the Carribean) and makes the case that, although this may call for highly improbable events, over a long enough period of time these can come to pass.
However, New Zealand's submergence (as well as erosive forces - see the U Waikato link) does explain the lack of landbased fossils.
What then, of the Tuatara? When I was growing up, the Tuatara was represented on the five cent piece, and typified as a rare lizard - preserved due to isolation on several island just off New Zealand's mainlands. They are actually uniquely-surviving lizard-like Sphenodontians, creatures that flourished 200 million years ago. Further, they show unique cold-climate adaptions over the original warm-climate sphenodontians. That's not unexpected in the time that they've been isolated, but it suggests they were in New Zealand when it was in a warmer climate. It seems to me less likely than that they rafted as recently as 25 million years ago, subsequently disappearing in their home location.
Neither explanation is fully satisfactory. On the one hand, New Zealand entirely lost its land-based fauna. On the other hand, two uniquely survived - at least until recently, and certainly after New Zealand's purported submergence.
It remains a puzzle for the moment.
Further discussion of this unusual find includes a number of reference links.
In broad terms, I very much agree with him. Cricket is far less "sportsmanlike" than it has been and it should be. Sledging (abuse on the field) should be verboten, and players should be honest about whether out was out.
But: "we are not playing cricket in the 1950s," Ponting said.
Of course not. So much has changed since then.
Jeffery (and many others) can bewail the modern generation's lack of decency and courtesy, but that's really nothing to do with it.
In a word, as Ponting said, it's professionalism. No, not the sort of professionalism that encourages people to do a proper job of what they do. Professionalism as in, they get paid an awful lot.
Simple. When money becomes the driving value, other values go out the window. Nobody can argue that. It's happening everywhere
If you want to complain, complain about that general trend: the replacement of all other values with monetary value. It's been intensifying globally for the past 25-odd years. Why sit on your hands? You could start by using what power you have, for example voting for those with a stronger preference for keeping the influence of the dollar out of areas that should be strong in human or community values.
Or stop complaining.
Wednesday, January 30, 2008
"The cultural prohibition of never speaking ill of the dead has always been in conflict with the desire to avoid the stench of hypocrisy in the nostrils as one unwillingly complies. As Paddy McGuinness himself never regarded such middle-class prohibitions as valid, neither will I.
Paddy's genius, in his later bibulous years, lay largely in his ability to deal in elaborately constructed illusions. Unlike Paul Sheehan ("Thinker, sceptic, commentator, cultural warrior", January 28), I was never able to detect, in those years, any trace of intellectual honesty or coherence in the illusory and often muddled word pictures that he painted of the fictional people he sought to parody.
Such straw men were daily constructed by Paddy only to be swiftly dispatched by what he no doubt regarded as his rapier-like mind. But they were without substance and their dispatch was intellectually meaningless. Paddy became embittered with a world that failed to recognise what he regarded as his genius, so he turned on it, and on himself, and tried to destroy both. He only succeeded with himself.
Les MacDonald Balmain
Bill Hayden and Bob Carr also give their view on him. One thing Hayden shares with McGuiness is apostasy. Hayden shed his republican principles to become Governor General; McGuiness shed earlier vestiges of leftism to become a right wing apologist.
Apostasy bemuses me. But my religious, political and ethical principles have remain unchanged since formed between ages 13 to 17. But apostasy in itself is not a sin. And Carr was enumerating McGuiness' part in the recent demise of the conservative government. He was more woolly than Gerard Henderson, somewhat on a par with Michael "Duffer" Duffy. I've seen McGuiness' shortcomings most succinctly detailed in the above letter. Follow the top link and you'll find another letter about his readiness to flout conventions about speaking ill of the dead.
The blog Larvatus Prodeo carries some comment on Hayden's words on McGuiness, referring to the latter's pretension to being a middle class "friend of the working classes" by the overlaying of class struggle with a "crass struggle" - an intentional mobilisation of conservative "battlers" (working class) against the non-conservative "intelligentsia" (read middle class) - and Hayden's part in that. There's numerous comments at bottom of that blog entry has an illuminating dialogue on the intersection between Hayden and McGuiness.
Update 31_jan-08: ex-PM Paul Keating has added fuel to the flames: "The quality of the Australian press will rise simply because his vituperation and contumely will have been excised from it." Apart from a few specific examples of McGuiness hypocrisy, Keating makes the quite valid point that McGuiness spent his [later, at least] columnist time fulminating against middle-class elites - when McGuiness was one himself, particularly as a poster boy for the Howard government.
Tuesday, January 29, 2008
Kevin Rudd had made some Australia day speech about us being lucky to a vibrant, young country; in citizenship ceremonies around the country, people agreed.
Meanwhile, my Australia day was rather typical:Going to the beach; playing in the pool with the kids (a large beach ball with an Australian flag design bounced around in the water); watching the cricket with a beer; eating a sausage sandwich & dipping a lamington while a bloke played Highway to Hell (decidedly un-hellishly); watching The Simpsons Movie.
The kids loved the pool best.
The Herald's editorial was on the republic. It began: "AUSTRALIA Day may not be the best day for critical thinking. It's OK for beer, barbecues, beaches and, of course, shameless self-adulation. It is a good day for congratulating ourselves on who we are and what we have achieved. Self reproach is not so welcome. Yet how can we escape it when 220 years after Governor Phillip first raised the Union Jack in Sydney, it is still flying above our heads? What happened to the Australian republic?"
Thursday, January 24, 2008
There's an order of fish called Lophiiformes. The most well-known species is the deep-sea Anglerfish, so-called because of the lure they use for attracting prey. But there's something stranger than that.
With the Anglerfish - as for most Lophiiformes - the male's digestive system degenerates when mature - so he cannot eat. With an extraordinary sense of smell, he locates a female by the pheromones she releases. The male then bites the female's side, and releases an enzyme that digests the tissue of her body and his mouth. The circulatory systems then fuse, and the male's organs all waste away - except the gonads. This chimera now has everything needed for reproduction.
Evolutionary oddity #2: the giant tube worm.
Protozoa are mobile, single-cellular animals. Metazoa are complex, multicellular animals.
Then there are Mesozoa - literally, "middle animals". The major group, Dicyemida, are parasites residing in squids and octopuses.
Thus it has been concluded that these creatures evolved to the most efficient design necessary to survive in that environmental niche. Evolution is about developing the best fit to environment. At times, that constitutes an "arms race" between species; other times it involves a paring back.
Survival is what counts, not persistently marching up a metaphorical hill. The metaphor is more akin to negotiating an endless, multi-path maze. There are many directions that work, some are dead ends, and sometimes there's a park bench to rest at - there's no specific goal other than to be.
Gould, SJ (2002): I Have Landed; Jonathan Cape, London.
Wednesday, January 23, 2008
"The worst capital crisis since world war two". - surely he exaggerated.
"Everything will be hunky dory once the US banks have all released their results. Then everyone will know the extent of exposure to sub-prime debt - it will be quantified - and the market will settle down". He was either bignoting himself with extravagant claims or, more likely, trying to talk a little calm into the jittery markets. As if that quantification will calm the nerves of goold old bipolar capitalism. More likely to send the markets into fresh spirals, in fact.
This is where numbers meet emotion head on. It is _not_ a rational business; markets thrive on self-perpetuating sentiment.
"It's a crisis of credit." Possibly a more apposite comment. The world now runs on inter-linked credit, and that's where it all started: with the packaging of high-risk (sub-prime) loans with other standard debt into inscrutible financial instruments which nobody really understood. Those instruments were spread out (sold) onto the global market before the risk factors started unravelling - that is, low-documentation (and thus high-risk) US borrowers started defaulting. It's exactly akin to a contagion in its incubation period spread around a financial world that is more tightly interconnected than ever before.
So all the capitalists have caught cold. (Australia's sharemarket closed down each day for over two weeks solid, including the biggest one-day fall since September 11 2001).
But it's no laughing matter for the average punter: we're all capitalists now by default, since so many of us have their superannuation at stake. But is it time to worry? Not really: all you need is perspective. This chart will demonstrate that in a historical context, these earthquakes are just blips.
And so the US fed dropped interest rates by a whopping 75 basis points (0.75%) - while meeting outside their regular schedule, on a public holiday to boot. One commentator said this was against the script - it wouldn't have happened in Greenspan's time.
Which may not be a bad thing - it seems to have worked for the moment. The Australia market is recovering, although some say it's too late to avoid a US recession.
I expect it to provide the markets with a temporary fillip only. But that may be what the Feds are seeking: a pause, while nerves are calmed.
Is it all under control? The US Federal Reserve tries. The EU tries (by releasing swathes of liquidity onto the market). But the game is becoming faster and harder all the time as global markets increasingly integrate; and rules are changing all the time.
Friday, January 18, 2008
Another book from the library. Michael Denton's Evolution: A Theory In Crisis.
Found out that this book kicked off the re-clothed evolution push known as intelligent design.
Of course, this meets the profile previously listed for books claiming an assault on evolution. Not least, Denton's reaching beyond his academic training.
You might think there's no prizes for stating the obvious, but from memory this is the first time the words have come from a Prime Minister. That counts for a lot, both in terms of leadership and intent. And Japan now hears and understands the clear message.
The skirmishes continue, at all levels.
Wednesday, January 16, 2008
Such authors ipso facto exploit the fact that their audience is relatively untrained, and must accept the technical statements and trains of logic as givens. They also exploit the general audience's lack of experience in moving outside the boundaries of human timescales, hammering doubts that something as complex as a mammal could grow from nothing. Since human history is a speck on the timeline of earth's history, such puzzlement is easy to exploit.
Another common strand is selective use of sources, often quite out of date. A misrepresentation of the nature of advancement of scientific theory is also quite likely, in particular to belittle a "theory" that keeps on changing - yet that is how it should be in the constant refinement of knowledge.
All these flaws are present in the next two books reviewed here.
Today, it's "Not By Chance!", by Lee Spetner, a physicist who collected notes in his spare time, and wrote the book after he retired.
Of course it's not by chance, Lee! It's a combination of random mutation and selective forces. If it wasn't through natural (and, in recent times, human) selective pressures, we wouldn't even be amoebae.
My notes on this book return time and again to Spetner's misrepresentation of evolutionary theory, in the specific and the general - no more so than in the book's title. He (and other such writers) simply do not understand the nature of change over time, such as the cumulative benefits of small change - not that result in unworkable organisms, but changes that don't impact viability.
By way of contrast, in Gould's Eight Little Piggies, some very lucid examples are given of change, for example via different organs that perform the same function (a two-for-one redundancy) or organs that can fulfil different functions and thus bridge a gap (the one-for-two).
Spetner often presents inappropriate (or, at the most charitable, grossly self-serving) analogies, and is often loose with his language in a way that belies his apparent careful analysis.
Most of his analysis centres on genetics, which is something I don't feel properly qualified to comment on. But a critique on this front is available at http://home.wxs.nl/~gkorthof/kortho36.htm. Not a difficult read.
Spetner bookends the treatise with some religious perspective, which give some insight into his keenness to attack randomness. Sensibly, he keeps these outside the body of the book.In the preface, he bewails atheism in the modern world. In the epilogue, he quotes from the Talmud in favour of a creationist intervention. Of course, this doesn't per se invalidate his arguments. But teleology is not science.
Gould, Stephen Jay (1994): Eight Little Piggies. Penguin, London.Spetner, Lee (1998): Not By Chance! The Judaica Press, New York.
Tuesday, January 15, 2008
I rifled through it, but found that all its references were to the Bible; there were no references to scientific sources.
I left a note for the librarian, and later got a call back. She agreed with me that it was incorrectly classified, and said it would get filed under religion. She wanted to cross reference it to evolution, but by that point I wasn't going to argue the toss.
Dewey 576 is a scientific classification. It is not religion, philosophy or religious philosophy.
I am keen to read well-sourced books that refute some aspect of current evolutionary theory. There is no requirement to conform to current theory: paradigm shifts come from challenges to orthodoxy. This is how knowledge is advanced and refined.
But that book was not about science.
This is a simple case. To follow are some less trivial examples of misguided attempts at anti-science.
Monday, January 14, 2008
Recapping on the Cambrian explosion: this was pretty much the beginning of modern multicellular animal life about 530 million years ago. In The Lying Stones Of Marrakesh, Stephen Jay Gould characterised this as constituting the greatest of all mysteries: "the causes of both the anatomical explosion itself and the 'turning off'of evolutionary fecundity for generating new phyla thereafter."
This has troubled biologists since before Darwin, and is less likely to be due to a simple gap in the exposed fossil record than to other phenomena, such as an extinction event covering the preceding Ediacaran fauna (sessile - non-mobile sponge-like marine animals). That's just a guess, but it parallels what happened 65 million years ago (the KT event, the end of the dinosaurs), when a meteor caused mass extinctions and specifically allowed mammals to proliferate.
The Cambrian Explosion saw the emergence of most major animal body types (phyla), bar the relatively insignificant marine bryzoa.
I'll restate a key passage of Gould's book Wonderful Life:
"The major argument of this book holds that contingency is immesurably advanced by the primary insight won from the Burgess Shale - that current patterns were not slowly evolved by continuous proliferation and advance, but set by a pronounced decimation (after a rapid initial diversification of anatomical designs), probably accomplished with a strong, perhaps controlling, component of lottery." (p301)
(Here, decimation doesn't refer to the literal reduction by one-tenth, but more the common understanding of much more dramatic paring to a relatively small fraction.)
If you can picture this as a spindle diagram, as Gould suggests, the direction of time would be bottom to top, and the spindle's width at various levels would represent diversity. And the appearance of animal body types would be like a christmas tree - the bottom would depict a small diversity of type, followed by a rapid (relatively instantaneous) expansion, followed by a gradual reduction. This is probably contrary to popular understandings of evolution of animal variety, as being either like an inverted cone - a constant increase in variety - or perhaps like a diamond, where a constant increase is followed by a constant decrease.
example of a spindle diagram
Gould depicted the Cambrian phenomenon as one of sudden explosion of so-called disparity - that is, sudden appearance of a variety of fundamental animal body types, or phyla.
This is where it gets interesting: he notes that in recent studies, he "concluded that the pattern of maximal early breadth is a characteristic of lineages at several scales and times, not only of major groups at the Cambrian explosion". In effect, the bottom-heavy christmas tree shape happens often. He "surveyed the entire history of marine invertebrate life - 708 spindle diagrams at the level of genera within families". With only one exception, he found lineages that arose early in the history of multicellular life - Cambrian or Ordovician periods - had spindles with 'centre of gravity' less than 0.5 - ie more like a christmas tree than a diamond.
This is certainly food for thought. Why such a regular pattern?
The KT experience does suggest that mass extinction permits remaining life to proliferate into the ecological vacuums, but there is no immediate suggestion that this happened in the Cambrian explosion. Yet the disappearance of the Ediacarans shortly beforehand (in geological terms) must have left a gap.
In The Lying Stones Of Marrakesh, Gould details evidence of phosphorised embryos in precambrian rock [the phosphorisation process can preserve soft tissue that would otherwise decay, but it works only on very small entities], with some suggestion that modern animal phyla had emerged before the Ediacarans disappeared. Then there is the SSF (small shelly fauna) of early Cambrian times to account for.
The story continues, and there are obviously more discoveries to come, more theorising. The mystery is too big to remain unaccounted for too much longer.
Gould, SJ (1989): Wonderful Life. Penguin, London
Gould, SJ (2002): The Lying Stones Of Marrakesh. Vintage, London.
Sunday, January 13, 2008
It's The Variety Of Life, by Colin Tudge. Via a survey of all life - at the high level at least - it provides exactly the perspective on biological descent that I've always been looking for.
It starts at the highest level, kingdom, and chapter by chapter breaks down all life into taxonomical categories, based on evolutionary history - ie a cladistic approach.
In the normal approach to taxonomy, one can look at the topmost level of life and go on down. The general breakdown of life is:
This gives a successive refinement of all animals, although there are sometimes sub- and super- levels interspersed to provide further refinement.
If you look at animals in particular, you would typically start at the phylum level. That is, dividing the animal kingdom by fundamentally different body types. There's about 32 animal phyla detailed here - although this number can vary widely depending on who's calling the shots, this seems to be a typical number.
Trouble is, most of those phyla are either small and insignificant, or marine. You'd wade through a lot to get to those that would have any meaning to most people on a day-to-day basis - that is, chordates (includes all animals with a backbone, which covers nearly all large animals), molluscs (covering shellfish and snails), and arthropods (mainly insects and crustaceans).
Unlike the typical simple listings of phyla given most places, where each phylum is accorded equal status in the headings at least, in a series of wonderful diagrams this book branches everything gradually from the top level, progressively dividing off the like from the unlike. In that sense, phyla with commonalities are grouped together, and branch off at the same time.
Cladistically speaking, there would be a term for just about every grouping, and these terms are well covered.
The narrative goes into detail about each successive breakdown, discussing all the biological similarities and differences. The book can be traversed as a map, with each chapter providing further diagrams in the cladistic breakdown, accompanied by a narrative that is thrilling in its clarity and enthusiasm.
Each diagram gives a pointer to following chapters that further breakdown the grouping under discussion. Although this navigation method could do with some improvements for those wanting to follow the maps - page references would help to lead from one diagram to both the following and preceding ones, and the full set would benefit by being reproduced in one hit at the beginning - these are minor distractions on what is, on the whole, a wonderful book.
The author is not dogmatic, and fully discusses differences of opinion on how the journey proceeds at each point, without disparaging those whose map would differ.
Thoroughly recommended as a reference book, or as one that can be read from beginning and end - albeit not it one sitting. There's too much life to cover.
Tudge, Colin (2000): The Variety Of Life. Oxford University Press, New York.
Friday, January 11, 2008
They're all meant to be united in a detailed understanding of biology, but writings on the subject often betray the specialist's perspective on the other scientists involved in the quest for knowledge.
What I have read sometimes reveals the bias of the particular discipline. If I personally have a bias, it would be towards the sweeping overview of natural history. I find geneticists (such as John Maynard Smith and George C Williams), to paraphrase Mark Twain, all seem to talk about sex but not do anything about it. This apparently places me around the middle rung in the hierarchy.
I think it was Stephen Jay Gould who revealed that a traditional bias of paleontologists was that taxonomists (those essential scientists who analyse similarities and differences between species) are sometimes disparaged as being akin to stamp collectors.
John Maynard Smith in turn revealed that a traditional attitude to paleontologists had been to wish they would "go away and find another fossil, and stop bothering the grownups".
Smith bookended this with context. By way of introduction, he claimed that in the modern synthesis of evolutionary theory that emerged in the 1940s, paleontologists took part, but essentially only to confirm the facts uncovered by "the rest of us", and not to propose any new theory.
This at the beginning of an essay that ultimately praised paleontologists, and Gould in particular for advancing theory in recent times. Then again, Smith admitted to some surprise at the knowledge revealed in the narratives of paleontologists (ably assisted by geologists, climatologists and the like). Genetic analysis is relatively silent on major events such as mass extinctions.
Paleontology is often regarded as being insufficiently hard a science specifically because it often inclines to persuasive narratives, whereas geneticists would have you believe they own the realm of detailed analysis and logic.
Yet the geological and fossil records are thoroughly essential for an understanding of the origins, history and direction of life.
Maynard Smith, J (1984): Did Darwin Get It Right? Penguin, London.
Williams, G.C. 1996. Plan and Purpose in Nature. Weidenfeld & Nicolson, London.
Thursday, January 10, 2008
Something In Between ***
Simmons was born in Tennessee to parents who wholeheartedly embraced the Bible Belt's values. Caught between his upbringing and a taste for the dark side, his conflicting, reflecting world - We'll See is one of the great hangover songs - bears a resemblance to the wild young Steve Earle in both style and content, without ever compromising his own voice.
Now, for good measure, the latest from doppelganger #1:
This Must Be Ground
Stephen Simmonds is een Zweeds/Jamaicaanse soulzanger met een gedegen muzikale achtergrond. Dit is goed te horen aan zijn mooie, uitgebalanceerde liedjes.
In 1997 had Simmonds een flinke hit met het prachtige Tears Never Dry, een duet met Lisa Nilsson. Het album Spirit Tales volgde en toen is het een tijd stil geweest rondom de Zweed. Met This Must Be Ground toont Simmonds aan zich nog steeds makkelijk te kunnen meten met soulartiesten uit Amerika en Engeland. Single Where Is My Love zou heel goed hoge ogen in de hitlijsten kunnen gaan gooien, het funky Mother Mary toont aan dat Stephen goed naar Prince heeft geluisterd terwijl hij op Who Is Gonna Give You Love een heerlijke jazzy soulballad ten
gehore brengt. Een veelzijdig artiest dus, deze Stephen Simmonds. Hou je van poppy soul en loepzuivere vocalen, dan is This Must Be Ground een aanrader.
Etc etc. (Well, he is Swedish.)
As Dave Graney would say, what better place to hide. Stealing my identity via the internet will not be easy. Just try googling my name.
For those who were seeking Dave Graney, there's something slightly more relevant here.
Wednesday, January 09, 2008
Reminds me of when I was going through my small collection of National Geographics to index all I had regarding evolution. I noted an article on a new dinosaur find, "Archaeoraptor", in the November 1999 issue.
However, I remembered something from an essay by Stephen Jay Gould, and looked up his 2002 book I Have Landed (his final, posthumous volume of essays).
In short, the specimen was put together for fun and profit from two different fossils. The duplicity was noted twice before National Geographic published, but they hadn't done their verification and went ahead.
They apparently published a retraction in October 2000 - which edition I did not have.
National Geographic is not a peer-reviewed publication. Although it aspires to the scientific, it is more akin to popular press in this respect.
Evolutionary theory advances rapidly these days, and it is important to keep up. However, I recommend sticking to articles that reference respected academic papers, and outside that stricture take the popular press - including NG - with a grain of salt.
Tuesday, January 08, 2008
Stephen Jay Gould's book Wonderful Life is subtitled "The Burgess Shale and the Nature of History". Its twofold perspective discusses a) The Burgess Shale, an extremely fertile lode of fossils from the Cambrian period (characterised as an "explosion" of new life forms), close to the dawn of multicellular animal life; and b) the history of scientific thought on the Burgess and on Cambrian life.
It's a great read - one of my favourite books of the last year. It provides much insight for the general reader into evolution and the history of life, although I have to say that much of what it says makes much more sense after having read a fair bit of background on biology and evolution.
In this post, I will give an outline of the book; in subsequent posts I will comment on some specific issues raised.
The first chapter gives some background on evolutionary thought - more specifically, it goes some of the popular conceptions and misconceptions of evolution. Gould is particularly disparaging of the common depictions of evolution as a series of progressively more complex beings, culminating with humans as a pinnacle of achievement.
The next chapter places the Cambrian period in the context of Earth's history, but more specifically gives some background on the discovery of the Burgess Shale.
The following chapter, comprising the bulk of the book, traces in detail the history of scientific discovery from the Burgess Shale, and in particular the early scientific mis-steps in analysis of the life forms represented by Burgess. It brings us up to date (specifically, to 1989) on the current consensus of scientific opinion on a number of animals that were originally represented as arthropods (the phylum containing diverse animals such as crustaceans, insects, spiders and trilobites). It specifically recounts the reconstruction of a number of very odd creatures - and includes a number of very good illustrations of those creatures made especially for this book.
However, the journey - for me at least - reaches its apex with the final, fifth chapter, in which Gould synthesises a number of lessons learnt from the study - particularly via some of his own research in several earlier papers. This chapter outlines a number of significant insights, discussion points - and contentions that are or should be contentious at least. This chapter provides much food for thought, which I hope to canvas shortly.
Gould, SJ (1989): Wonderful Life: The Burgess Shale And The Nature Of History. London: Penguin.