The Iroquois organized their kinship groups into matriarchal clans,

Hi kadamhari825,

That's an interesting question. Let's go through a couple of points first:

1. Relative whose is the possessive form of both who and which. This means that when whose points to a noun before it, that noun could be a living thing or an inanimate object.

2. Relative whose can be replaced by an of-construction, but such constructions are often quite awkward in comparison with whose-constructions.

The important thing about (2) is that there are two ways of looking at that replacement. The traditional view is that we must insert a the when moving from whose to of which.

3. The club whose members...

4. The club the members of which...

5. The club of which the members...

All of these, (3), (4), and even (5), are grammatically correct. People don't normally use the structure we see in (5), but it is acceptable. But while we can't say the club whose the members, is it possible to say the club members of which or the club of which members, without inserting a the before members? I find those constructions a little odd.

Of course, if we're not aware of the difference, we should take a call on which option is better. Whose is both shorter and less awkward, so that's the one we should choose.