Continous and Discontinuous Variation

[ggxoxo]

Hi guys,

Can you please look at Question 3 graphs of the Short Answer of the 2009 Exam 2 Biology paper:

http://www.vcaa.vic.edu.au/vcaa/vce/studies/biology/pastexams/2009/2009biol2-w.pdf

Can someone please explain to me how that is an example of continuous variation (and please don't say it's common sense because it's height). I want to know how it is continuous variation looking at the graph because the graph shows the heght trait fall into discrete groups (i.e. no intermediate groups betwen the heights; it even separates the bar graphs). So why is it continuous?

Please reply ASAP!

[lexitu]

Hey

The reason why it appears as though it is falling into discrete groups is because they have given ranges for the heights. Of course, within the range of, let's say, 20-21, plants may be 20.0023, 20.2556, or any other number.

Here's a nice rule that should generally hold true: if you use the word "much" to describe it, it is continuous, whereas if you use the word many to describe it, it is discrete. So I would ask someone how much they weigh, but I wouldn't ask them how much fingers they have, I would ask how many fingers they have, which in most cases will be five.