Course details
Tutors
Aims
This course aims to:
- ask and answer ‘why?’ questions in biology
- understand how the principles of optimality, constraint and contingency can be used to explain the evolution of organismal form and function
- become acquainted with evolutionary biology’s most intriguing unsolved questions
Course content
The older we get, the more we take the natural world for granted. Only when we take a step back can we appreciate just how many questions should be asked about living organisms: why do they appear and act the way they do? Are biologists limited to describing life, or can we explain why life evolved the way it did? In each session of this course, you will learn both the particular answers to a set of intriguing biological conundrums, and from these a general principle that applies to all life on Earth will be elucidated. For example: a common biological principle explains why carrots are orange, why all vertebrate eyes suffer from a blind spot, and why in 1818 a single mutation changed the course of world history. Throughout the course, you will therefore not only work through interesting biological case studies but also develop your own biological puzzle-solving skills.
We begin with some case studies that will help you learn how to ask and answer ‘why?’ questions in biology. The rest of the course then uses these principles to draw out three principles that, when combined, can help us understand why life is the way it is: the principles of optimality, constraint, and contingency. The course closes with a discussion of evolutionary ‘cold cases’, traits in organisms’ that still pose a mystery to evolutionary biologists and await a satisfying explanation.
Discussion of your own ‘why?’ questions is strongly encouraged, and it is hoped that by the end of the course learners will be able to independently develop the outline of an answer to such questions. No prior knowledge is required to understand the course – only a curious mind and a love of asking questions.
What to expect on this course
All sessions in this course are interactive: each lecture raises many intriguing questions for group discussion, with lots of opportunity for interaction with both the course tutor and your fellow learners. The lectures are accompanied by a multimedia slideshow which ensures an engaging and immersive experience.
Course sessions
1. The principle of optimality (I): the best of all possible worlds – an introduction to how ‘why?’ questions in biology can be asked and answered, an introduction to the principle of optimality and how optimality hypotheses can be tested.
2. The principle of optimality (II): challenging the Panglossian paradigm – biological examples are discussed in which the principle of optimality appears to be violated, and we begin to consider why a population might evolve traits that appear sub-optimal.
3. The principle of constraint: the art of the possible – evolution as a tinkerer rather than an engineer; biological examples are discussed in which underlying constraints (e.g. physical, developmental, cognitive) constrain the evolutionary trajectories that a population can explore.
4. The principle of contingency: replaying the tape of life – is evolutionary change explicable and predictable, or is the fate of species’ largely attributable to chance, unpredictable events? If the tape of life was re-wound and re-played, would similar species emerge?
5. Cold cases: the evolutionary enigmas yet to be solved – the course closes with a discussion of traits whose evolution remain a mystery, not yet being fully explicable via the three principles explored in this course (optimality, constraint, and contingency).
Learning outcomes
As a result of the course, you will gain a greater understanding of the subject and you should be able to:
- apply a systematic framework to develop answers to ‘why?’ questions in biology
- understand how optimality modelling can be used to predict and explain the evolution of organismal anatomy and behaviour
- explain how biological and physical constraints can limit the evolution of optimal phenotypes
- evaluate the role of contingency in evolutionary explanations
- become aware of some of the biggest unsolved mysteries in evolutionary biology
Required reading
There is no required reading for this course. See Course materials for supplementary reading once registered.