varying size of limpets on areas of shore

please, please could you send me any examples of coursework on the size of limpets in relation to their situation on the shore. desperate situation! thanks

Reply 1

Lucy

beppy

please, please could you send me any examples of coursework on the size of limpets in relation to their situation on the shore. desperate situation! thanks

If this is A2 coursework, you should probably be using the height:width ratio to represent the size of the shells. For best results, you should compare the limpet shell shapes on exposed shores with the limpets on sheltered shores. The height:width ratio of limpets is greater on exposed shores compared to on sheltered shores. This means that the shell shapes are taller and thinner on exposed shores as the foot (i.e. muscle) is always contracted to prevent dislodgement as wave action is much greater on exposed shores. To contrast, the height:width ratio of limpets is smaller on sheltered shores as there is much less wave action so the foot remains relaxed. This means the shell develops around 'relaxed' tissue, creating a flatter and wider shell.

If you are hoping to compare sizes on the same shore than the height:width ratios should be larger up the shore. This is because there is a more dessicating environment on the upper shore so the foot muscle contracts, creating a 'vacuum' which prevents desiccation. This time the shell develops around 'contracted' tissue, creating a taller and thinner shell. So for an investigation you could compare the height:width ratios of the limpet shells on the upper shore and then on the middle shore. There might not be much difference between the sizes as all the limpets are on the same shore, so I'm not sure if your results will be significant (in the sense of a statistical test).

Hope this helps, if you're not doing A2 coursework then I don't know how much use this will be :smile:

Reply 2

bone-machine

'This time the shell develops around 'contracted' tissue, creating a taller and thinner shell'

so far all iv got to go on to write my coursework discussion is that sentence!!...how come there is no information anywhere about the specific biology behind the tissue growing in relation to contractions?

does anyone have any idea where i can get some info on this particular issue...i have sooo much on the general biology of limpets (god bless the little beasties) but this is the thing that its most relevant to my hypoth and the internet and the books iv looked at so far DO NOT HELP!!!

in the vague hope that anyone will reply....any suggestions...??

Reply 3

Ralfskini

beppy

please, please could you send me any examples of coursework on the size of limpets in relation to their situation on the shore. desperate situation! thanks