Is there a way to identify which OTUs were merged at higher clustering thresholds?

Hello and thanks as always for Mothur’s many tools.

I’m trying to compare the clustering outputs across multiple thresholds (e.g., 3% vs 10%).

I’d like to generate a table that shows the hierarchy of OTU clustering across various thresholds (i.e., I want to know which 3% OTUs were merged together to create each of the 10% OTUs, or maybe just a select list of 10% OTUs).

Here’s an example of my desired output:

10% OTUs  3% OTUs
OTU0001  OTU0001, OTU0004, OTU0006
OTU0002  OTU0003,OTU0005,OTU0007,OTU0008,OTU0009,OTU0010
OTU0003  OTU0002,OTU0011

Does Mothur have a function that can do this sort of reverse-lookup?

I have some ideas for accomplishing this outside Mothur (using some combination of grep/sed and the .list file), but I’d rather not reinvent the wheel if it can be avoided.

Thanks in advance for any suggestions.

I think you are looking for the otu.hierarchy command,