Which test/model to use?

[mid06004]

Hello,
I have a question regarding what methods/tests/models I can use to analyze my data.

The data consists of different samples of teeth from different species of otters (8 species), from walruses (2 species), from sea lions (12 species), and from seals (17 species). These different teeth have different pathologies which are either malocclusions, caries, calculus, and periodontal disease. Now, I also have data on the diets of each of the different species of otter, walruses, sea lions, and seals which is expressed in numerical form under the heading "trophic level"...and this trophic level ranges from 3-5 in different species.
What I want to do is to see if there is a relationship between diet (which is expressed as a trophic level and the pathologies that are present in the teeth.

I was planning to use R, but I dont know which models to use, or how to use the data, so I was hoping someone could steer me in the right direction.
thanks for the help in advance

P.S. I have noticed that there is a gross difference between otters, which eat above the water on land, and seals, sea lions, and walruses which eat under water in terms of their incidence of pathology. What tests can I run to show this statistically?
thanks

[trinker]

I would lean towards multinomial/ordinal logistic regression (with pathologies as your DV and species, diet, tooth (I don't know your field but I'm sure that depending on the location in the mouth the outcome is affected). If you're doing it in R I'd recomend looking at these examples from UCLA's website:

Multinomial logistic regression (http://www.ats.ucla.edu/stat/r/dae/mlogit.htm)

Ordinal logistic regression (http://www.ats.ucla.edu/stat/r/dae/ologit.htm)