The theory of evolution

Material for Week 2 (Week of Jan 24 for posts the week of January 31)TopicReadingAssignment for next week’s post

:  Evolution

:  Etcoff Ch. 1 & 2

:  Please read the narrative below.  Use the suggested websites to familiarize yourself with the theory of evolution.  Use what you have learned about evolution in your reflection next week on chapters 1 & 2 of the Etcoff text, be sure to refer to material from at least 2 of the websites suggested below (be sure to clearly cite the websites you visited to ensure you get credit).  Post your reflections and by Wednesday February 2, and reply to another students post by Sunday the 6th.

For this weeks post:  Your posts on last week’s material (Self introductions and responses to the several questions I raised in the course material) are due by 11:59 pm Wednesday January 26, responses to another students post by NOON Sunday January 30.

Evolution and Darwin

We begin the course by considering how biology can explain human development and interaction.  The main theme of the Etcoff text is that we are treated differently by others based on our appearance, and many of the differences in our responses to people who are “prettier” compared to those who are not can be explained based on the theory of evolution.  The Etcoff book is one of many recent publications in the area of evolutionary psychology – a field that seeks to understand human behavior in light of the evolutionary pressures our species has faced in the past. Next week, we will focus on evolutionary psychology and the related area of sociobiology.  This week, we will look at the theory of evolution itself and the person who presented the modern version of the theory, Charles Darwin. Darwin’s theory (evolution through natural and sexual selection) is the single most revolutionary idea of the past 200 years, with wide-spread implications in all areas of life, including the understanding of social behavior.

Evolution through Natural Selection:  The theory of evolution through natural selection, first suggested by Charles Darwin in 1854, argues that species change through a simple process of competition between individuals.  Darwin was attempting to understand a puzzle about the nature of living things on earth. The puzzle was that at the same time, living things on earth are amazingly diverse (millions and millions of different unique species of living things), while being amazingly similar (all mammals have roughly the same skeletal structure, the same internal organs, at a cellular level the cells of all living things look the same, and at a molecular level all life on earth has DNA composed of the same 4 nucleic bases – although Darwin had no knowledge of DNA and the later discovery of this mechanism of inheritance is one of the great supporting arguments for the validity of his theory).  How could so much diversity, and at the same time so much similarity, be explained? The only explanation generally accepted for much of western history was that of divine creation.  But why would a divine creator create so many distinct life forms?  Why millions of different types of bugs?  And why create them all so much the same?  A theory that had become increasingly popular over about a century or so before Darwin was a theory called Evolution.  The theory of evolution argued that the similarity between species could be explained if we assume that all life started as a single form that changed (or evolved) over time into all the different forms we see around us.  The problem with the theory of evolution before Darwin was that there was no viable mechanism that would explain why change would happen – why would one original species change into other species?  Darwin’s great contribution to science was the discovery of that mechanism of change. Darwin’s theory, known as “Natural Selection” (and a later modification called “Sexual Selection”) has revolutionized our understanding of life, and nothing in the study of living things (including human development) can be fully understood without a grounding in evolution.  You can learn about the history and impact of the theory of evolution and about the evidence supporting the theory here:  http://www.ucmp.berkeley.edu/history/evolution.html, and more specifically, you can learn about the history of the theory here: http://www.ucmp.berkeley.edu/history/evothought.html.

One of the important facts about the history of the theory of evolution is that it was not Charles Darwin who came up with the theory – as we will discuss in more detail next week, Darwin proposed a viable mechanism for evolution, but the theory had been around for a long time.  Here is a brief review of pre-Darwinian views on evolution:   http://sci.waikato.ac.nz/evolution/DevelopmentEvolThought.shtml.

For your post next week, please discuss what you learned from at least two of the websites above, along with summarizing and discussing the first two chapters of the Etcoff text.  Be sure to clearly cite your sources, your post should be detailed and in-depth enough to demonstrate that you have thoroughly read and thought about the chapters in the book and that you have read the course material above and visited some of the websites I have recommended.  Each week, your points for discussion board posts will be based in part on how thoroughly you discuss and summarize both the readings and the course material from the previous week.  Also please keep the minimum length requirement for posts in mind.