# Re: where have all the etc.

Okay, let me repeat what you are saying in my own words as I
```understand it: There is a 'problem' in that I have insufficient
characters in my analysis. But in this partcular rabbit hole leading to
Wonderland the problem is that I have complete resolution and all sister
taxa resemble each other. My friends, that's no problem. That's a
solution.
```

How do you know it's a solution rather than a random quirk? Test that. Add more characters and try.

(Just a wild shot... are you sure you haven't changed your settings to neighbor-joining instead of parsimony? Neighbor-joining always finds only one tree, no matter how many of equally shortest length there are [and of course almost no matter how parsimonious they are]. I mean... sorry for implying you overlooked such a basic thing, but it's strange how all your analyses seem to find one tree.)

You'll note that each of the analyses uses some or many
```suprageneric taxa, and that each one has 13,  14, ? 11, 20, 9, ? taxa in
total. Now granted they all focused on the archosauriformes, but none
include any Choristodera, Doswellia, Cerritosuchus, Silesaurus,
Lotosaurus, Pseudhesperosuchus, Tropidosuchus, or various Youngina
[...]
```

That's true, and it's good that you include them all. But you have too few characters to sort them with any reasonable support. Your average Bremer support is probably 1.2.

```DM wrote: What, you have only 150 or so characters in your matrix, and
in spite of this you are so certain of your conclusions?!?```

When you have a single tree and everything makes sense, then the
end of the road has been reached.

Nope. You must then test whether you've _really_ reached the end of the road. If you have so few characters, the addition of just one more character is likely to change the topology. If you _have_ reached the end of the road, then the addition of 20 or even 50 characters (...or typos in the matrix!...) won't change the tree, except for 2 or 3 details and 20 or 30 precise bootstrap values. _This_ is the "enough is enough" phenomenon.

More characters mean more signal and more noise; but while the signal adds up, the noise averages out. More characters = better signal/noise ratio; high enough signal/noise ratio = enough characters.

"Everything makes sense" means that the tree is robust. Given your low number of characters, yours cannot be robust.

The ref is a JVP abstract... I'm sure several papers have been published on this meanwhile, though. I suggest googling for John J. [?] Wiens. I don't have much literature on this myself, though, and at the moment I unfortunately don't have time for anything, writing this e-mail included. I have to write up what I did in the lab for 3 weeks.

```I'm sorry to hear that the same cannot
be said of your theropod work. It must be frustrating.
```

What _is_ frustrating is that I don't find more characters, means, that I can't hop around the world to inspect the fossils, respectively that most of them aren't described in detail with good-quality photos. I'm not frustrated that I don't find fewer MPTs with such a ridiculous ratio of characters per taxon and so many question marks in most taxa. Such a matrix is simply incapable of producing a single well-supported MPT.

```Referees have brought this up, suggesting I use 20,000 taxa
and as many characters,
```

For 20,000 characters you'd obviously need a lot more than 20,000 characters!!!

```so this ratio-thing has been on my mind. As you
can well imagine, the prospect of so many taxa is daunting and I am not
that ambitious.
```
`(Are there even 20,000 fossil vertebrate "species" known?)`

```David, you mentioned you would need a week or so to get your 10
with the tall-headed hook-nosed ones. No problem. I can wait.
```

I'll need that week before I can _start looking for_ such characters. I don't have most of the primary literature on that part of the tree.

Should I send you Müller's paper & supp. inf., or do you have those? That would be a matter of a minute or two for me.

```DM wrote: I'll be in Paris to write my ~ Master's
Thesis under the supervision of
Michel Laurin. He could well have something.```

He does. My manuscript, cladogram and I think a matrix.
`Oh!`