Dear all,

I'm seeking help with modularity tests using the EMMLi package in R. I have 
developmental data for different species of mammals, and my goal was to 
group specimens in each species by age classes (e.g., neonate, juvenile, 
adult based on tooth eruption) and then test different hypotheses of 
cranial modularity following Goswami & Finarelli 2016 EMMLi: A maximum 
likelihood approach to
the analysis of modularity. Evolution 70:1622–1637. Some of those groupings 
are rather small, <10 individuals.

The first step is to generate a correlation matrix from the 3D array of 
landmark coordinates (Y), but when I do I get the message
Warning message:
In dotcorr(Y) : CVM has negative eigenvalue -1.1286357464565e-15

Will this will cause problems for the EMMLi model test, or I can I ignore 
it and move on? Also, does anyone have thoughts of the minimum number of 
samples one can use to compare modularity hypotheses? In Goswami & 
Finarelli, they show that reducing the dataset down to 10 individuals from 
48 still performs very well, but is there a true minimum? For example could 
I take the 3 largest individuals from each species for the test?

Thanks for any advice,

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