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Most of Horner's statements about Trex are in the process of being totally 
destroyed by Tom the Holtz  using, surprise, morphometrics. Tom has given a 
great series of talks on this. Jack has tended to get mixed up with relative 
versus absolute size, such as in the eye, or Jack has not taken allometry into 
account properly and relatively simple plots falsify much of what he says. 
Again, Jack's assertions about Trex were yet another just-so story that 
paleontologists have to get away from - a theory thrown out there without any 
real backing in the analysis necessary to make the point. This is, in part I 
believe, why Jack never really published these ideas in the traditional sense, 
just through that Dinofest transcription of his talk. I have always thought 
that we need to be more careful about the theories we put out to the public - 
when we get the forum to do so - or at least try to frame them more 
conservatively. This idea of Trex as an obligate scavenger is just too flimsy 
and unsupported by anything but anecdotes and should be approached with extreme 

Not that it is easy to avoid making extreme statements to the press. This 
became even clearer to me when I was interviewed by a press person after the 
Horner & Goodwin talk at SVP where they described microstructure of some pachy 
domes and interpreted them as suggesting they could not butt anything. I saw 
their evidence as 180 degrees differently in that they showed the dome to be a 
pretty messed-up pathological structure that you would expect from something 
that has had a few impacts. Will take much more work on my and their part but 
it is great we're both doing it. I have somehow become the de facto defender of 
head-banging in pachys although my real position is that a good case was made 
for it through the years starting with Galton and Davitashvili (although 
actually L. Sprague de Camp and Colbert). It has been obvious for a long time 
that the Bakkerian picture of 2 Stegoceras running towards each other is not 
probable - even mountain sheep tend to start far apart but bounce around and 
fidget until much much closer before butting - but the evidence is, imho, still 
decent for head butting as a good possibility. Goodwin and Horner and Ken 
Carpenter have reacted against that - in part bothered understandably by the 
popular media taking their butting to the extreme. However, to answer the 
question well will take the completion of my (and the other guys) on-going 
research following many detailed lines of functional inference and evidence. I 
don't know the answer but want to and will work to find it. Hope Mark and I 
will be sparring with reduced pachy head shields sometime over the next couple 

Now onto the press after Jack gave the talk for him and Mark. Remember my 
opinion was that I found it unconvincing but much is left to do. This is not 
verbatim but not far away.

Reporter: So you don't find their talk all that convincing?

Me: No I didn't, I think it was easily a good argument for the other side so I 
was not convinced.

Reporter: So you think they definitely butted heads?

Me: No, I think their arguments did little to argue against that and I think it 
is still a distinct possibility that needs more work.

Reporter: You won't just come out and say they butted heads?

Me: No, I want to do the work we need to do to allow or deny the possibility.

Reporter:  I can't report that, I need the simple and direct answer.

Me: Well, I'm not going to caricature my opinion just to spoon-feed readers. I 
think you are underestimating their ability to understand the complexity of 

Reporter: Well, I'll do something with the quotes.

Which, I assume, he did. Anyway it's tough and they always want you to go 
beyond your evidence to sensationalize. I won't.

And just to be clear, the so-called quantitative sciences have their own 
just-so stories. Currently in astrophysics and physics, etc. self-organized 
criticality is big and they all show these plots with points and straight lines 
fitted to them to support their inference of such. Funny, though, they never 
actually try different types of curves and test the fit. they just eye-ball 
them. The only one to do otherwise so far I know of is a paleontologist - 
Gunther Eble. Their just-so stories just have numbers attached - but they are 
no better.


Ralph Chapman, NMNH