Aidan Budd, EMBL Heidelberg Introduction to Evolution Aidan Budd SCB, EMBL-Heidelberg EMBL PreDoc Course Evolution Module Monday 5th December 2011

Aidan Budd, EMBL Heidelberg

Introduction to Evolution

Aidan BuddSCB, EMBL-Heidelberg

EMBL PreDoc CourseEvolution Module

Monday 5th December 2011


Introduction


It was...

•a multi-deadline weekend

•so I didn't get the preparation time I wanted

•I've tried to fit it to the context of the module and the course

•i.e. you're tired

•i remember - I did this myself in 2000

•trying to make it interactive/less passive

•but please bear with me


Aim

•Highlight some themes common to most (all?) discussions of biological/Darwinian evolution

•Hope this makes it easier to notice links/relationships between presentations etc. in this module

•Hope this helps think about topics in a more general way, making it easier to deconstruct/critique such analyses

•Feels like quite a lot of hope for a Monday morning


Focus

•On you and your current ideas on evolution

•You are impressively heterogeneous

•Difficult to present introductory content that won't be much too detailed for "half" of you and much too basic for the other half

•Those with more experience on the topic are encouraged to support those with less

•Try to address this by having you think on your own, and talk in groups, about specific topics/issues of interest/relevant to you

•some people learn better like this

•hopefully it helps us all stay awake


What do we mean by "evolution"?



1.try to write, on your own, without discussing it, a definition of the topic we discuss when talking about Darwinian/biological evolution

•make notes on which topics/issues you think need to be in the definition

•makes notes on other terms you might want/need to carefully define to support this defenition

• if you have trouble, try to make notes on what you find difficult about this

• I'll tell you when to stop

2.compare your definition with your neighbour

•try and write a consensus one you both agree on

• if this is difficult, try to make notes on where the problems might come from

3.we'll discuss the definitions together



•we'll discuss these definitions as a group• I'll describe what I want in such a definition

•a volunteer will give their definition, and any particular problems they encountered with producing it

•ask you for any important differences with your definitions


Evolution - a Process of Transformation/Change

the change in the inherited traits of a population of organisms through successive generations.

the change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift.

Random House Dictionary

the historical development of a biological group (as a race or species)a theory that the various types of animals and plants have their origin in other preexisting types and that the distinguishable differences are due to modifications in successive generations; also : the process described by this theory

Merriam-Webster Dictionary

Futuyma, Douglas J. (2005). Evolution. Sunderland, Massachusetts: Sinauer Associates, Inc. ISBN 0-87893-187-2.

the process of change in lifeforms over generationswikipedia


Evolution - a Process of Transformation/Change

the process of transformation that produces differences between ancestors and descendants that are not due to direct environmental influencesdriven by genetic differences between ancestors and descendants


•Why are we interested in evolution?Key conceptsCommon misunderstandings


Focus on you...

What do you see as the most interesting aspects/implications/applications of evolutionary biology?

What do you consider some of the more important common misunderstandings people have of evolutionary biology?

What are key issues/topics in evolutionary biology you feel it is important to understand to be able to critically assess/interpret evolutionary analyses

Your opinions on these issues have considerable impact on how you approach a discussion of evolutionary biology

So it's useful to examine/highlight/consider these opinions and how they might differ from other people's


Exercise

You are making a short film to be shown at the start of an exhibition of evolutionary biology at a natural history museum

The film should

• excite the audience about the topic address common misunderstandings you expect they might have teach them about several key, basic principles of how evolution occurs

Make notes, silently, on your own, on:

1. the aspects of the topic that you think would make the audience excited by it

2. common misunderstandings you would want to address

3. some basic, key principles about how evolution occurs that you would want to address


Make notes, silently, on your own, on:

1. the aspects of the topic that you think would make the audience excited by it

2. common misunderstandings you would want to address

3. some basic, key principles about how evolution occurs that you would want to addressExample:1. Comparison of dog (Canis lupis) and marsupial wolf (Thylacinus cynocephalus) skulls - astounding convergent evolution (can show you if you're interested...)2. Humans evolved from chimpanzees3. That genetic changes that drive evolution are not all "adaptive" i.e. evolutionary changes are not just the result of natural selection

Choose a favourite for each of these points in discussion with your neighbour, then we'll find out what we've come up with


What about Darwin...?

•Theories accounting for observed biodiversity that implied historical change of species existed before Darwin

•Darwin provided simple, mechanistic, "algorithmic" explanation for how this might occur

1-Organisms pass their characteristics on to their descendants, which are mostly but not completely identical to their parent organisms. 2-Organisms breed more descendants than can possibly survive. 3-Descendants with beneficial variations have a better chance of surviving and reproducing, however slight, than those with non-beneficial variations. 4-These slightly modified descendants are themselves organisms, so repeat from step 1. (There is no stopping condition.)


What about Darwin...?

•Mechanistic explanation is powerful as it allows us to make predictions

•Key further development was integration with genetics to form the "new synthesis" - the substrate on which inherited evolutionary changes occur


Right Here, Right Nowhttp://www.youtube.com/watch?

v=ub747pprmJ8•A video for a Fatboy Slim track that references evolution

•While we're watching it, make notes on:

•What (if anything) it "gets right" about how we think about evolution?

•In what way does the video misrepresent the way we believe evolution occurs?

•Do you think there is a danger that this misrepresentation could cause serious trouble for people's ability to understand what we think really happened? Why?

•Discuss your answers to these questions with your neighbour - we will then discuss them together


Further reading

•Darwin's Dangerous Idea, D Dennett

•http://www.ucmp.berkeley.edu/exhibits/historyoflife.php

•http://tolweb.org/tree/phylogeny.html

Documents

Aidan Budd, EMBL Heidelberg Introduction to Evolution Aidan Budd SCB, EMBL-Heidelberg EMBL PreDoc Course Evolution Module Monday 5th December 2011