After the recent, fairly epic post about using homeopathy to teach ‘how science works’, and the time spent turning it into a (hopefully useful) scheme available as a pdf, I’m trying five shorter posts again this week. Instead of books, however, I’ll be sharing some ideas for teaching what can be one of the trickier topics, evolution. I’d like to emphasize that it’s tricky not because it’s difficult in itself, but because of the manufactroversy we see mentioned in the media and the mind-boggling time scales often involved. I really enjoy teaching evolution and my aim is that the following posts will show how it can be fun, rather than difficult.
A lot of evolutionary ideas make intuitive sense to students. I start by discussing adaptations, putting them in the context of a characteristic, some aspect of anatomy or behaviour, that gives an advantage over other individuals. This is an opportunity to remind students of the importance of linking structure and function – in this case, the adaptation itself with the advantage it offers. More able students may understand quickly that these advantages also come with a ‘cost’, while others may need a little time to deal with this.
Comparing different animals that have similar adaptations (such as teeth and claws for hunting) and animals in apparently similar situations that have different solutions to the same problem (foxes are solitary hunters/scavengers while wolves are pack predators) can be illuminating. You may choose to consider how humans fit into this context, or leave this discussion for a later time. I tend to finish the ideas of adaptations by summing it up. I suggest that to be Successful, an individual must have the Three S Factors.
- Survival (avoid being eaten, freeze to death or similar)
- Snacks (get enough food)
- Shagging/Sex (have offspring)
Funnily enough, this seems to be an idea that sticks in their heads! Once we’ve covered the background, it’s time to move on to random variation within a population, followed by selection pressure. Some thoughts on teaching these will be appearing later this week.