Archive for the ‘legal battles’ category

evolution in action: ceratopsians and the paleontological evidence for evolution

September 24, 2010

Nearly everybody familiar with evolutionary theory and anti-evolution movements is familiar with the old refrain claiming that “the fossil record does not support evolution.”  However, such claims are extremely misguided, and stem from a major misunderstanding of what the fossil record does, in fact, show.  While one could pick any one of hundreds of fossil lineages to examine, we’ll look at one that most people are familiar with, the ceratopsian dinosaurs. To get a partial idea of the diversity of this group, I’ll post some pictures before continuing.

chasmosaur skull on display at AMNH

triceratops on display at AMNH

Protoceratops display at AMNH

While I’ve only shown a few specimens here, the ceratopsian lineage itself is far more diverse.  However, for the sake of ease and sanity, we’ll only look at a few key ceratopsians for our comparison.  For some basic paleontological background, ceratopsians are a Cretaceous group, thus existing towards the end of the reign of the dinosaurs.  The group as a whole was relatively successful, with a distribution throughout Western North America, Asia, and possibly Australia and South America as well.  They were herbivores, and tended to live in large groups.  In phylogenetic terms, the ceratopsians shifted from a relatively lightly built, at least partly bipedal, basal form such as Psittacosaurus, through slightly more robust forms such as Protoceratops, and ultimately towards larger forms such as Triceratops. Now I don’t want to speak in terms of “progress” or “orthogenesis” here; I’m not trying to imply that there was something inevitable about how these forms developed. Rather, it’s just the way it happened. Selective pressures pushed towards that direction, and natural selection responded by building larger, more robust forms.  Let’s take a quick look at the basic sequence:

psittacosaurus on display at AMNH, public domain pic from wikipedia

another psittacosaurus picture, this time on display in Copenhagen. Also from wikipedia.

Protoceratops on display at Carnegie Museum of Natural History, from Wikipedia

Triceratops at AMNH, from Wikipedia

With these specimens, you can get a pretty good idea of how body plans shifted during the phylogenetic history of the Ceratopsians.  However, don’t get the wrong idea here; it isn’t necessarily so that Psittacosaurus evolved into Protoceratops evolved into Triceratops. This isn’t how the fossil record works.  Rather, an organism like Psittacosaurus evolved into an organism like Protoceratops, and so on.  These specific examples show us a basic picture of the transition that occurred. They aren’t the full story.  We’re looking at over a hundred million years between us and them.  We don’t have the full picture.  Look at today’s biodiversity, and compare it to what’s available in the fossil record.  The fossil record itself is like trying to understand a person’s life by looking at a photo album, most of the pictures missing, with a picture of an individual, we’ll call him Bob, as a toddler, then as a highschooler going to the prom, then maybe as a middle-aged man with another younger man (perhaps his son?), then a funeral announcement.  We can get a basic idea of how his life unfolded, but there are many, many things that we can’t answer about his life.  This is the way the fossil record works. In order to understand how evolution operates over time, one has to look at the basic patterns visible in the fossil record. Sure, you can’t get a complete, full, exact picture of every species-to-species transition, but you can get a pretty good idea of what actually did happen in an evolutionary sense.

Another thing to note about evolution, something which is often overlooked, is the fact that evolution can, in fact, transform entire bodies as a whole. The transmutation in body plan visible in our ceratopsian lineage is a complete one, with changes in cranial anatomy (just look back at some of the ceratopsian skulls shown to see it), body size, stance, and (as we’ll look at in a minute), sacral (a fancy word for the region of the backbone that runs through the pelvis) anatomy.  What you’re looking at is not natural selection working on just one trait at a time, but rather many traits, all interacting with each other, all being tweaked slightly through the differential reproductive success of different individuals, not as distinct parts, but as a whole.  People far too often think of natural selection as acting on just one trait at a time.  Sure, it can happen like that in rare cases, but a more full understanding of evolution implies that it is the body as a whole which is acted upon by natural selection.  Yes, individual traits play key roles in reproductive success. But it is the entire body, not merely one trait, which is the agent of reproduction.  Sure, you might have a reproductive edge because you have bigger horns than your opponent.  But you ultimately get to mate because you’re a complete organism, not just one sexy part.  Now that I’ve gotten your attention by talking about reproduction, let’s look at some hips:

psittacosaurus sacrum at AMNH

If you’re having trouble finding the sacrum in this picture, look to the right of the “gastroliths” arrow, right between the little guy’s (not sure if it’s male or female, but I digress…) hind legs. It’s the bone structure shaped more or less like this: )I(

Now onto the next specimen, Protoceratops:

Protoceratops sacrum, AMNH

Look in the same place on this one, right between the hind legs. I apologize about the crappy images with the last two pictures. I took both of them a few years ago, without this purpose in mind.  But I have them, so might as well use them as examples.  Now let’s check out a Triceratops sacrum:

Triceratops sacrum, AMNH

With these three sacrums, you can see how evolution has shaped one specific body part over time. However, after looking previously at the full bodies of these dinosaurs, its much easier to view this for what it is, natural selection tinkering away at one body part as it shapes the whole body.  Regardless, this series of sacrums at least helps to illustrate the relationship between these organisms.  But keep in mind, once again, that it is the entire body that evolves, not just one part.  What paleontologists look for in the fossil record is not “transitional forms”, but “transitional features”, such as our sacrum example, when trying to define evolutionary lineages (phylogenies).  This happens precisely because superficial traits (size, weight, etc) are relatively fluid.  In order to fully understand an evolutionary lineage, it is necessary to look at specific traits which are carried throughout a sequence.  While our sacrum example is not a perfect one, we can at least roughly view how one might find such a trait.  Yes, you can see it change through the lineage, but it is also possible to build a relatively complete picture of how the sacrum has changed throughout its evolution.  Therefore, it could be used to help understand phylogenetic relationships between ceratopsians. Thus, while natural selection does operate on entire bodies, specific traits are also extremely important in defining exact evolutionary sequences.  Both angles are necessary in order to fully define an evolutionary sequence.

Anyway, let me shut up before I make this post any longer/more painful to read.  So what exactly does our quick look at ceratopsians do?  Besides being a (relatively dull) way to kill a few minutes, it also provides an often overlooked example of an evolutionary lineage.  So read up on your ceratopsian evolution (I’ve tried to stay away from the boring, terminological stuff for the sake of a quick introductory glance; Donald Prothero’s Evolution: What the Fossils Say and Why it Matters has a really good discussion of ceratopsian evolution, and would make an extremely good starting point for looking at evolution in the fossil record in general), and be ready next time someone tries to explain away the basic examples of paleontological evidence for evolution like Tiktaalik, Ambulocetus, or Archaeopteryx.  Provide an example of a full lineage such as the ceratopsians, rather than one “transitional form” in a vacuum.  It’ll provide a much stronger proof if you’re ever trying to explain evolution to someone with an open mind that doesn’t know much about the subject.

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Defending William Jennings Bryan

August 18, 2009

I recently watched (once again…it’s a film I’ve watched many times) the classic film interpretation of the Scopes Trial, Inherit The Wind.  While I have a deep appreciation for the film as someone with an interest in evolution and anti-evolution movements, the portrayal of Bryan in the film is problematic.

Throughout the film, we see Matthew Brady (the character representing Bryan) portrayed in a wholly alien way to someone familiar with William Jennings Bryan.  Brady was a Young Earth Creationist, convinced that the Earth was created in 4004 BC (as given by the Ussher chronology).  The real Bryan held a rather different view, which was compatible with an old Earth (the “day-age” interpretation of Genesis).  While many people instantly think of Young Earth Creationists when the term “Creationist” is mentioned today, Bryan’s position was a relatively common one in his day.  It may seem like I’m jumping on minutia here, but there is a key difference between Brady in the film and Bryan in real life in this area.

One other extremely blatant misportrayal of Bryan within the film comes near the end of the film, when Brady states his desire for a much harsher penalty than the Scopes character recieved.  In reality, Bryan was not trying to ruin Scopes.  In fact, Bryan offered to pay Scopes’ fine.  Thus, Inherit the Wind portrays Bryan in a negative light compared to what he actually was like during the trial. 

A final note: Bryan was not some defeated buffoon come the end of the trial.  He did not give up on the anti-evolution movement.  In fact, Bryan was preparing to expand it before his death(Larson 198-199).  While he was upset by the trial, and   clearly took a beating at the hands of Clarence Darrow, he was not broken.  And the trial was clearly not a victory for evolutionists.  How could it have been?  The trial ended, and Scopes was found guilty.  Scopes fine was eventually discarded on a technicality, thus preventing the defense from challenging the ruling in a higher court.  Evolution would continue to be excluded from classrooms for years to come.

Therefore, when watching a film such as Inherit the Wind, remember that the work is inherently a work of fiction.  Bryan really wasn’t as bad as they made him out to be.  Inherit the Wind, while a classic film, has its own historical problems, as I have partially demonstrated.  However, the film does much to expose the public perception of a battle between science and religion, a battle that is not always necessarily present.  This concept is an old myth, popularized by the likes of Draper, through the conflict thesisInherit The Wind offers a good illustration of this myth, thus making the film worth watching even with its historical errors.  While events such as the Scopes Trial certain had religious and scientific influences and consequences, the perception that science and religion are always necessarily at each other’s throats is inherently and deeply flawed.  Let us remember that when we see Bryan portrayed as a religious zealot yearning for the crucifixion of a science teacher who overused his right to think.  As we have seen, this is not the case at all. Yes.  Social factors were at play in the Scopes Trial.  But this was not a simple case of Science VS. Religion.

 

Works Cited:

Larson, EJ.  Summer For The Gods: The Scopes Trial and America’s Continuing Debate Over Science and Religion.  Basic Books, New York, 2006

Kitzmiller v. Dover (pt. 2 of 2)

June 12, 2009

And now for the part everyone thinks of when Kitzmiller v. Dover is mentioned: the legal maelstrom following the events described in Kitzmiller v. Dover (Pt. 1 of 2).  The legal battle that would ensue as a result of the school board’s attempt to challenge the teaching of evolution in Dover, PA included some key players in the evolution-creation struggle, including Kenneth Miller, Kevin Padian, Barbara Forrest, Nick Matske, the NCSE, Steve Fuller, and Michael Behe.  Notably absent from this trial was the Discovery Institute, who had saught to distance themselves from the school board once the board began to stray from legal techniques suggested to Buckingham in a phone conversation (Humes 77, 101). 

There were a few notable aspects of this trial.  First, it offered the first true legal test of Intelligent Design in a classroom setting.  However, perhaps more notable is the Creationist heritage of the textbook supplement Of Pandas to People that came to light during the trial.  As described by Barbara Forrest and discovered by Nick Matzke, Of Pandas and People is nothing less than a creationist book with all references to “creationism” changed to “intelligent design” after McLean v. Arkansas declared the teaching of “Creation Science” unConstitutional (see here).  The transitional form “Cdesign Proponentsists”, a failed edit in an unpublished draft of Of Pandas and People helps to confirm this linaeage (although this transitional fossil was not used in the trial; Forrest and Gross 329). It is worth noting that on September 6th, 2005, the defense in Kitzmiller v. Dover attempted to have Forrest barred as a witness.  However, this move failed (Forrest and Gross 327), and would go on to establish a religious basis for Intelligent Design.  In reference to Of Pandas and People:

“Forrest used charts [here] showing the continuity between creation science and ID.  Her Pandas analysis centered on early drafts that FTE [the book’s publisher) had amazingly kept.  There were at least five: (1) Creation Biology Textbook Supplement (1983); (2) Biology and Creation (1986); (3) Biology and Origins, (1987), and (4) two 1987  drafts entitled Of Pandas and People. Pandas was published in 1989, followed by the current 1993 edition” (Forrest and Gross 329)

Forrest’s testimony, combined with that of Kevin Padian and Kenneth Miller, established both the religious undertones of Intelligent Design and also the strength of evolutionary theory (Padian’s powerpoint slidesand testimony, available here,  offer a detailed analysis of the strength of evolutionary theory, and the weaknesses of ID). It is worth noting Kevin Padian’s blunt yet honest assessment of the disclaimer leading to Kitzmiller v. Dover, namely that “Padian bluntly and effectively stated that in confusing students about science generally and evolution in particular, the disclaimer makes students ‘stupid”  (quoted from Memorandum Opinion in previous link).

Perhaps as striking as the testimony of Padian and Forrest is that of Michael Behe. As acknowledged by Behe, if the definition of science were altered to include Intelligent Design as a scientific theory, then astrology would become a scientific theory as well:

Q In fact, your definition of scientific theory is synonymous with hypothesis, correct?

A Partly — it can be synonymous with hypothesis, it can also include the National Academy’s definition. But in fact, the scientific community uses the word “theory” in many times as synonymous with the word “hypothesis,” other times it uses the word as a synonym for the definition reached by the National Academy, and at other times it uses it in other ways.

Q But the way you are using it is synonymous with the definition of hypothesis?

A No, I would disagree. It can be used to cover hypotheses, but it can also include ideas that are in fact well substantiated and so on. So while it does include ideas that are synonymous or in fact are hypotheses, it also includes stronger senses of that term.

Q And using your definition, intelligent design is a scientific theory, correct?

A Yes.

Q Under that same definition astrology is a scientific theory under your definition, correct?

A Under my definition, a scientific theory is a proposed explanation which focuses or points to physical, observable data and logical inferences. There are many things throughout the history of science which we now think to be incorrect which nonetheless would fit that — which would fit that definition. Yes, astrology is in fact one, and so is the ether theory of the propagation of light, and many other — many other theories as well.” (from cross-examination of Behe, available here)

As a result of the information presented here, legal precedent, and the rest of the data presented during the trial, Judge John E. Jones III had enough information to strike down the motion to read a disclaimer questioning the strength of evolutionary theory and referring students to copies of Of Pandas and People.  As exposed during the trial, the text has a distinctly Creationist heritage.  As accepted by Behe, to alter science to include Intelligent Design as a scientific theory would also deem astrology a valid scientific theory.  While testimony illustrating the religious motives of board members such as Alan Bonsell and Bill Buckingham exposed the religious nature of Dover’s anti-evolution movement, expert testimony also illustrated weaknesses with Intelligent Design as a whole.  Thus, while Judge John E. Jones III struck down the school board’s attempt to challenge evolution in Dover, expert testimony within the trial can provide some framework for future attempts to incorporate Intelligent Design into the American science classroom.

Works cited:

Forrest, B. & Gross, PR.  Creationism’s Trojan Horse: The Wedge of Intelligent Design. Oxford University Press, Oxford, 2007

Humes, E. Monkey Girl: Evolution, Education, Religion, and the Battle for America’s Soul. HarperCollins.  New York. 2007

Kitzmiller V. Dover (pt. 1 of 2)

June 12, 2009

And now for my first deep consideration of legal fights in the Creation-Evolution struggle.  I’ll discuss Kitzmiller v. Dover here, and then delve into other key trials in future posts.  Kitzmiller v. Dover, fought over a Dover, Pennsylvania school board’s decision to read a disclaimer in classrooms in the school district claiming that evolutionary theory “has gaps” and referring students to copies of the textbook supplement Of Pandas and People to learn about intelligent design, which is proposed as an alternate theory to Darwinian evolution.  The text of the disclaimer is as follows:

“The Pennsylvania Academic Standards require students to learn about Darwin’s Theory of Evolutionand eventually to take a standardized test of which evolution is a part.

Because Darwin’s Theory is a theory, it continues to be tested as new evidence is discovered. The Theory is not a fact.  Gaps in the Theory exist for which there is no evidence.  A theory is defined as a well-tested explanation that unifies a broad range of observations. 

Intelligent Design is an explanation of the origin of life that differs from Darwin’s view.  The reference book, Of Pandas and People, is available for students who might be interested in gaining an understanding of what Intelligent Design actually involves. 

With respect to any theory, students are encouraged to keep an open mind. The school leaves the discussion of the Origins of Life to individual students and their families.  As a Standards-driven district, class instruction focuses upon preparing students to achieve proficiency on Standards-based assessments.” (in Kitzmiller v. Dover memorandum opinion, p. 1-2.  for link, click here).

The adoption of this disclaimer followed a 6-3 vote in which it was decided that:

“Students will be made aware of gaps/problems in Darwin’s theory and of other theories of evolution including, but not limited to, intelligent design. Note: Origins of Life is not taught” (Kitzmiller v. Dover memorandum Opinion p. 1).

These statements set up the controversy.  Here, we have a school district deciding to challenge the teaching of evolution.  With the development of the classroom disclaimer,we have a strategy.  However, there is more to Dover than the adoption of standards challenging evolution.  In this instance, we have the documentation to provide a good look at the forces governing this decision.

The decision to challenge evolution in Dover’s classrooms was pushed heavily by schoolboard member Bill Buckingham and fellow board member Alan Bonsell (as described in detail in Lebo 2008, Chapman 2008, and Humes 2007). Buckingham, during the course of debating the teaching of evolution, is quoted as stating “Two thousand years ago, someone died on a cross.  Can’t someone take a stand for him?” (Numbers p. 392).  This statement, by a leader of the push to challenge evolution in Dover’s classroom suggests a religious rationale for this challenge.  Other sources of information (for example, the fact that the Thomas More Law Center, the self-declared “sword and shield  for people of faith” offered legal protection if the school board were to challenge evolution around July 2004; the vote to challenge evolution passed October 18, 2004, and the disclaimer was published November 19th 2004 (see here for general background)) confirm this suggestion.

However, the Dover school board was not unanimous in their decision to challenge evolution, as suggested by the 6-3 vote over changing the district’s standards.  Following this vote, the three board members who moved against the measure  (Jeff Brown, Casey Brown, and Noel Wenrich) resigned (Humes 98-99).  Casey Brown’s resignation statement can shed some more light on the religious tensions present on the Dover school board in 2004:

“Sometimes in order to fulfill the requirements of our office, we must put aside our personal feelings and beliefs.  It is not always an easy thing to do—but it is what we must do in order to properly perform the duties and responsibilities of our office.

In the past year, regretfully, there seems to have been a shift in the attitudes and direction of this board.  There has been a slow but steady marginalization of some board members.  Our opinions are no longer valued or listened to.  Our contributions have been minimized or not acknowledged at all.  A measure of that is the fact that I myself have been twice asked within the past year if I was “born again.:  No one has, nor should have the right, to ask that of a fellow board member.  An individual’s religious beliefs should have no impact on his or her ability to serve as a school board director, nor should a person’s beliefs be used as a yardstick to measure the value of that service.  However, it has become increasingly evident that is the direction the board has now chosen to go, holding a certain religious belief is of paramount importance.

Because of this, it is quite clear that I can no longer effectively function as a member of this board…” (quoted in Humes 99)

This statement confirms the importance of religious belief with regards to the operation of the board. Ironically, had the school board not been taken to court, it is entirely possible that social studies curriculae in the district would have been altered to challenge the separation between Church in State in America (Humes 100, Lebo 60).  Largely as a result of this separation, the Dover School Board lost Kitzmiller v. Dover.

Following the passage of the anti-evolution measure, with teachers refusing to read the statement and parents such as Tammy Kitzmiller unwilling to have their children’s education compromised (Lebo 48-53), in cooperation with the National Center for Science Education, the ACLU, attorney Eric Rothschild, and others, filed suit… 

Works Cited:

Chapman, M.  40 Days and 40 Nights: Darwin, Intelligent Design, God, oxyContin, and other Oddities on Trial in Pennsylvania.  Collins.  New York. 2008

 Humes, E. Monkey Girl: Evolution, Education, Religion, and the Battle for America’s Soul. HarperCollins.  New York. 2007

Lebo, L.  The Devil in Dover: An Insider’s Story of Dogma v. Darwin in Small-town America.The New Press, New York, 2008

Numbers, RL.  The Creationists: From Scientific Creationism to Intelligent Design. Harvard University Press, Cambridge, 2006