Low evenness between phyla/genera MiSeq v4

Theory behind mothur
1

Hi

Just wondering if anybody ever experiences a low evenness in their sequences. I am sequencing gut samples from fish. 5/6 phyla total but one phyla dominates the samples (anywhere from 50-99%)?

I am aware of differences in 16s copy number, but could it just as well be a true reflection of the environment. Lots of otu’s just low evenness?

Wondering if this is common

Thank you

2

completely plausible. If it’s novel for your habitat you might want to do something quantitative to prove the evenness disparity-i.e. FISH