Tuesday, August 30, 2011

Tuesday Morning Comics #7

Today's comic comes from our Young Earth Creationist friends over at Answers in Genesis (AiG).  Here we see, pictorially represented, a standard argument used by AiG and Creation Ministries International (CMI) (indeed, I heard Richard Fangrad use this argument himself).  Evolution and Creation, they argue, are both interpretations of the same evidence.  The Christian looks at the facts of the natural world, such as fossils and genetic similarities between organisms and mass extinctions and sedimentary rocks, and interprets those objective points of data through the lens of scripture.  This provides them with an overwhelming belief in the majesty of a creator who shaped the world according to a literal reading of Genesis.  The evolutionist looks at those same facts and interprets them through the lens of The Origin of Species and other such evolutionary texts, and comes to an overwhelming belief in the truth of blind, random evolution.  The only difference between the two viewpoints is their explanatory framework.

Friday, August 26, 2011

Foolish Wisdom - 1 Corinthians and a Defence of Higher Education

In 1 Corinthians 3:18-20, Paul has some seemingly searing words for academics:

‘Do not deceive yourselves. If any of you think you are wise by the standards of this age, you should become “fools” so that you may become wise.  For the wisdom of this world is foolishness in God’s sight. As it is written: “He catches the wise in their craftiness”; and again, “The Lord knows that the thoughts of the wise are futile.”’

Again, in 1 Corinthians 1:20, Paul writes, ‘Where is the wise person? Where is the teacher of the law? Where is the philosopher of this age? Has not God made foolish the wisdom of the world?’

Tuesday, August 23, 2011

Genetics and the Origin of Species

The mule is a famous example of a sterile hybrid.  Photo circa 1937

We are officially almost finished our summer-long read through Dobzhansky’s evolutionary classic, Genetics and the Origin of Species.  We have spent an awful lot of time talking about genetics – about mutations, and how their value is context-dependent; about chromosomes, and how breakdowns during cell replication and gamete production can lead to large-scale changes; about natural selection, and how it affects gene frequencies; but now it is time to actually roll up our sleeves and delve into the ‘origin of species’ part of Dobzhansky’s book title.  Last week we explored polyploidy, a form of instant speciation that is solely due to reproductive incompatibilities brought about by chromosomal mismatch.

In other words, last week we saw that a simple genetic cause (chromosomal duplication) led to instant speciation, simply because the polyploid and its parental form could not successfully reproduce (or, more precisely, their offspring could not reproduce); that is, the polyploidy event caused a reproductive barrier to form between the parent and its polyploid offspring.  They were reproductively isolated.

Tuesday, August 16, 2011

Tuesday Morning Comics #6

Here's another bit of irreverent humour from Saturday Morning Breakfast Cereal, poking fun at the Creationist misuse of 'theory'.  When biologists speak of evolution, they can speak of evolution as a 'fact', by which they are referring to things like experimental evolution in which change in a species is documented and not inferred, and they can speak of evolution as a 'theory', by which they mean that evolution is an explanatory framework which includes and explains, under a unifying whole, a disparate group of facts that had heretofore been considered separate.  Thus the Darwinian theory of evolution explains, among other things, the genetic similarities between all living things; adaptation; biogeography; palaeontology; morphological similarities; homologies; and a whole host of other things.  When Creationists say that evolution is 'just a theory', they mean something very different.  They quote the biologists who use the word theory, but they do not use it in the elevated sense of the biologist; instead they use it in its colloquial sense, as 'sheer speculation' or 'unproven'.  The above comic captures fairly well (and hilariously) the frustration that biologists feel over the consistent misuse of this important word.

Thursday, August 11, 2011

Even You Can Create a New Species - The Curious Case of Polyploidy

There are currently 1.7 million named species of plants, animals and algae on this planet.  This does not include the vast array of bacteria and other such single-celled creatures.  And those are only the ones we know about – based on rates of discovery, the National Science Foundation estimates that we have only described 10% of the world’s true diversity.  Most of these organisms will likely be small or marine, but not all; twenty-five species of primates have been discovered since 2000 alone.  And then this diversity really only scrapes the surface of the total diversity that has ever existed, with a mind-boggling number of plant and animal species known only from the fossil record.

Theodosius Dobzhansky, in Genetics and the Origin of Species (1937), presents, in chapters 7-9, an introductory treatment on the topic of speciation.  He brings genetics and natural selection and various observations together to provide a compelling account of how new species are formed.  This would be the groundwork used by Enrst Mayr, who would develop the modern Biological Species Concept.

Tuesday, August 09, 2011

Communion and a Call for Social Justice

I have, for most of my life, gone to a church that practices weekly Communion (what you may also know as the Lord’s Supper, or Eucharist, depending on your background).  Unlike Catholic traditions, my evangelical church would pass out tiny little cups containing grape juice, and would have tiny little portions of unleavened bread.  We would, as a body, take these little tokens/symbols (for us, not Sacraments) and ‘partake’ of them.  That was always the phrase.  ‘Partake’.  It was never ‘eat’ or ‘digest’ or, heaven forbid, ‘masticate’.  We were much more respectful than that.

Saturday, August 06, 2011

Natural Selection

We continue with our (seemingly unending) walkthrough of Dobzhansky’s evolutionary classic, Genetics and the Origin of Species.  Today we will finish his chapter on Selection; the rest of the book will be a cakewalk in comparison.

Natural selection was not unique to Darwin, having been recorded by numerous others, including the watchmaker-hypothesis’ William Paley.  But for these pre-Darwinian writers (with two minor exceptions, noted in the opening of the sixth edition of the Origin of Species), natural selection was simply a way of preserving the created species.  Forces would try to alter the species into less-adapted products; natural selection would winnow out those mutant forms, allowing the species to remain relatively pure.  Selection, then, was like a hangsman, killing off what nature abhorred.  Darwin’s major insight was to raise the status of natural selection from preserver and destroyer to the primary creative force in nature.  (I am indebted to Stephen Jay Gould’s book The Structure of Evolutionary Theory for much of this discussion).

Tuesday, August 02, 2011

Tuesday Morning Comics #5

Today's comic was clearly inspired by the teaching of Creationism in the school system.  Unfortunately, it is more insulting than inspired.  The school board in question is represented by a large-bodied cartoonish imbecile who is apparently not as 'evolved' as modern humans.  This comic would lead you to believe that the school board has less intelligence than a Neanderthal!  I am somewhat torn by this comic - I understand why people would find it funny, but this sort of name-calling is less than helpful, and is a real mischaracterization of the people who make up the Creationist movement.  Contrary to the public perception, Creationists are not idiots.  Philip Johnson, for example, is a leading Creationist and Intelligent Design proponent, yet teaches law at the University of California - Berkeley.  Last I checked, UCB does not hire slobbering morons.  The people that I have met who are strong Creationists may be stubborn to the point of annoyance, but they are intelligent people with, often, intelligent critiques.  It is just that their body of knowledge tends to be in a different direction than the body of knowledge that evolutionists have.