rigorous exercise

I almost forgot! I just had a paper published, on evolutionary comparisons between the nervous systems of two mollusks.  This stuff is a little deep, but I will put the link to the abstract below.  

This gives me an idea -  perhaps we can throw a really deep evolutionary concept at each student.  There are five students in the class who have signed up for the biological perspective - I can come up with five very terminology-heavy evolutionary discoveries, and have one student research each of them and do a paper or presentation on it.  The five students on the English side can have a similar experience, though I can’t speak for the projects that can be created. 

http://www.ncbi.nlm.nih.gov/pubmed/20029185?itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum&ordinalpos=1

evolution all around us

I am thinking a good way to start the course is to have students explore the concept of evolution through familiar ideas and people around us.  I got this idea while listening to NPR, where a commentator was discussing the evolution of how we listen to music.  Here are some other putative ideas for exploration of this concept:

• comedy / comedians
• car design
• Brett Favre
• hearing aids
• game theory
• spending habits

A way to approach these concepts, and explore their evolutionary history, would be to research the history behind how they came to be what they are today.  More than that, though, evolution is not just history but what did NOT happen. 

• history
• adaptations that led to the present
• weaknesses (imperfections)
• false starts
• radiatative events
• punctate events
• putative parallel histories – what could have been?

And so on.  Evolution  is so much more than talking about what IS, but also an assessment of what COULD have been.  It is difficult, and complicated, and takes critical thinking behond the obvious.  This is an exercise I have never done, but I am up to the challenge.

a new direction

Dr. Caruso’s posts have shown me a new side of Evolutionary thought.  This, combined with the daily reading I am now doing, and so on … leads me to think of this course differently. 

One of my great concerns has been finding an intersection between literature and science – there is only so much scientific history to be taught, and there is a wealth of literature that reflects the thinking of evolution at the time.  I’m not certain there is a good parallel of topics that can encompass the breadth of evolutionary history.

What if, instead, we just approach evolution as a thought process? Evolution is occuring all the time – not just in literature, not just in nature, but also in society, in humanity, in social mores, in weaponry, etc etc.

My original thought was that we would set up the course thus:  begin with the biological definition of evolution, and the history of that theory, and then move on to explore the literature of the era. 

But I think there is so much more involved.  We need to understand the roots of evolution, the soul, the essential makeup of this theory.

What if we start off thinking of examples of well known people or ideas or such, and the way that they have evolved into what, or who, they are?

Keep in mind, Darwin might not have even put together his data and thought processes into the theory of evolution, were it not for work in other fields.  Particularly, the work of geologists such as Cuvier were influential.  But essential parts of the theory may never have come about, had Darwin not read Thomas Robert Malthus, who published his theories in economics three decades prior to Darwin’s fated voyage on the HMS Beagle.

These are my choices???

Tidarren sisyphoides.  Cute little spider. The females are much larger, and perhaps because of this, the males have very large testicles.

Female spiders are notoriously mean after mating, and like other spiders these females will attack and kill their amorous counterparts, just post-copulation.  (How rude!!) 

The males are weighted down by the aforementioned testicles.  They have a hard time running away from the attacking females.  So …

So ….

http://www.cbc.ca/quirks/archives/03-04/images/tidarren.jpg

They pull off one of their own testicles, to allow themselves to run faster! It is an evolutionary advantage – remove a testicle, run faster, live to copulate another day.

Neanderthals and Us

The Humans Who Went Extinct: Why Neanderthals Died Out and We Survived by Clive Finlayson

It is commonly thought the Homo sapiens are somehow superior to the Neanderthals, that somehow our species “beat” theirs, either by crowding them out or outsmarting them.  But really, it was chance that led modern day humans to dominate the world.  Chance is a huge part of evolution, and one that should not be discounted.

The Neanderthals were built like wrestlers, tough and large, and therefore adapted well to the woodsy areas of northern Eurasia.  Here they could easily hunt their prey, and long distance running was not necessary. 

About 30,000 years ago,  the forests of Eurasia receded, and tundras and steppes took their place. 

Suddenly being built tough and slow was no longer an advantage, but rather lean endurance and speed were essential to hunt animals who were more dispersed across treeless areas.  Enter the Homo sapiens, who had evolved in the planes of Africa and were better adapted to these conditions.

The success of modern day humans, and “beating out” the Neanderthals, was due to an environmental quirk that could easily have gone a different way.

This is a perfect example of evolution: the best fit in the environment, wins.  We are nought but accidents, just like every currently living creature on earth.

The Response

Here is one set of responses to the 10 questions from the NY Times:

http://www.nytimes.com/2008/08/24/us/WEB-tenquestions.html

This is What we are Up Against

This is a widely circulated set of questions designed to cast doubt upon the theory of evolution:

Ten questions to ask you biology teacher about evolution

1. ORIGIN OF LIFE. Why do textbooks claim that the 1953 Miller-Urey experiment shows how life’s building blocks may have formed on the early Earth — when conditions on the early Earth were probably nothing like those used in the experiment, and the origin of life remains a mystery?
2. DARWIN’S TREE OF LIFE. Why don’t textbooks discuss the “Cambrian explosion,” in which all major animal groups appear together in the fossil record fully formed instead of branching from a common ancestor — thus contradicting the evolutionary tree of life?
3. HOMOLOGY. Why do textbooks define homology as similarity due to common ancestry, then claim that it is evidence for common ancestry — a circular argument masquerading as scientific evidence?
4. VERTEBRATE EMBRYOS. Why do textbooks use drawings of similarities in vertebrate embryos as evidence for their common ancestry — even though biologists have known for over a century that vertebrate embryos are not most similar in their early stages, and the drawings are faked?
5. ARCHAEOPTERYX. Why do textbooks portray this fossil as the missing link between dinosaurs and modern birds — even though modern birds are probably not descended from it, and its supposed ancestors do not appear until millions of years after it?
6. PEPPERED MOTHS. Why do textbooks use pictures of peppered moths camouflaged on tree trunks as evidence for natural selection — when biologists have known since the 1980s that the moths don’t normally rest on tree trunks, and all the pictures have been staged?
7. DARWIN’S FINCHES. Why do textbooks claim that beak changes in Galapagos finches during a severe drought can explain the origin of species by natural selection — even though the changes were reversed after the drought ended, and no net evolution occurred?
8. MUTANT FRUIT FLIES. Why do textbooks use fruit flies with an extra pair of wings as evidence that DNA mutations can supply raw materials for evolution — even though the extra wings have no muscles and these disabled mutants cannot survive outside the laboratory?
9. HUMAN ORIGINS. Why are artists’ drawings of ape-like humans used to justify materialistic claims that we are just animals and our existence is a mere accident — when fossil experts cannot even agree on who our supposed ancestors were or what they looked like?
10. EVOLUTION A FACT? Why are we told that Darwin’s theory of evolution is a scientific fact — even though many of its claims are based on misrepresentations of the facts?

Monogamy vs. Polygamy – only a small difference?

Is it possible that only a small difference between two similar animals can cause one animal to be faithful and another to be a player?

The vole is a small rodent, and there are two varieties: the mountain vole and the prairie vole.

The prairie vole has been shown to be monogamous – they make a pair and remain bonded for life. In fact, if one of the partners dies, the other partner may die soon afterwards. (awwww)

Mountain voles are polygamous – they will mate with quite a few different partners throughout a lifetime.

By the current definition of species, these animals belong to different species. However, they are fairly similar.

It turns out that the main difference between the two animals revolves around oxytocin, the “bonding hormone”. The polygamous mountain voles bond less, it seems, because of a lessened sensitivity to oxytocin. (See link below.)

It is always interesting to observe two species which are closely related, who differ only slightly and in a measurable way. The implications are that accidental variations in an organism’s makeup can make huge differences in how they interact with the world.

http://www.thefreelibrary.com/Brain+receptor+shapes+voles’+family+values.-a012488361

The Panda’s Thumb

Stephen Jay Gould’s essay by the same name describes the unusual bone structure of the gentle animals.  Pandas do not actually have opposable thumbs, but rather one of their wrist bones is shaped in such a way that it looks like a thumb.  Since the ankle bones are also shaped like this, and the shape of ankle and wrist bones is controlled by the same gene, it appears this “thumb” was a result of random mutation.

The advantage that comes with the “thumb” is that pandas can eat their food of choice, bamboo, with an efficiency other animals cannot match.

Watch for this pattern: evolution is pretty much always driven by food or sex.

First post

What a lovely blog! I’m afraid I am not as adept at posting photos and so on.  However, perhaps my skills will evolve as this preparation progresses.  For now, I will rely on my teaching partner’s obvious skill to keep the blog interesting and pretty.

I appreciate Dr. Caruso’s dedication to the thought process behind evolution – a theory upon which virtually all science research is based. 

My most pressing thoughts regarding this course revolve around what specific concepts I should cover.  There is so much to know, so much to discuss.  Every day it seems I read more interesting findings that shed new light on the theory of evolution. 

Does one defend the theory? If so, how much class time should be taken with that? Does one teach the basic concept of evolution, that of allelic frequencies changing over time until eventually new species are created? (And what the heck are allelic frequencies, right?)

Or does one presuppose that the idea of evolution is generally understood? And the more loaded question – does one presuppose that the students “buy in”? And that gets me back to defending the theory. 

But if we presuppose the buy-in, then we can leap straight ahead and … well, still try to figure out what to teach.  The very interesting adaptations that have been developed by certain organisms to live in particular environments … the ancient organisms that are thought to be “links” between organisms which exist today … the molecular (DNA) changes that, though seemingly small, can make all the difference in a behaviour or appearance … and so on. 

In my future posts, I will probably begin sorting through my thoughts regarding all this.  Hopefully by the time the spring semester begins, I will have a good handle on the material I want to bring to class.