Hello everyone, I am new in the field of geometric morphometrics and have a question for my bachelor thesis. I am not sure how many landmarks I should use at most in regard to the sample size. I have a sample of about 22 individuals per population or maybe a bit less (using sternum and epigyne of spiders) with 5 populations. I have read a paper in which they use 18 landmarks with an even lower sample size (3 populations with 20 individuals, 1 with 10). But I have also heard that I should use twice as much individuals per population as land marks...
Maybe there is some mathematical formula for it to know if it would be statistically significant? Could you recommend some paper? Because of the symmetry of the epigyne I am now thinking of using just one half of it for setting landmarks (so I get 5 instead of 9 landmarks). For the sternum I thought about 7 or 9 landmarks, so at most I would also get 18 landmarks like in the paper. I would also like to use two type specimens in the analysis, but I have just this one individual per population... would it be totally nonesens in a statistical point of view? Thanks very much for your help! Best regards Lea -- MORPHMET may be accessed via its webpage at http://www.morphometrics.org --- You received this message because you are subscribed to the Google Groups "MORPHMET" group. To unsubscribe from this group and stop receiving emails from it, send an email to morphmet+unsubscr...@morphometrics.org.