Re: attack on dinosaur--horrific video

[don ohmes <d_ohmes@yahoo.com>]

"Secondly, you could make the same argument about the 
multituberculates, which had been around since the Late Jurassic, if
 not the 
haramiyids and the tritylodontids, which are as old as the dinosaurs." -- David 
Marjanovic

Same argument? Those animals have chisel-type incisors? Capable of cutting down 
trees, chewing through copper wire, etc.? Further, they were around for along 
time w/out apparent damage to the dinos ... Same argument? I think not. Not 
that it matters, see below. -- Don

"Just call it a speculation, then." -- David Marjanovic

Thanks for the suggestion, but I will call a best-fit cartoon a "best-fit 
cartoon". A best-fit cartoon has passed through a process; the accuracy and 
number of observations it provides explanation for have been at least 
qualified, and if possible quantified; and it has been compared to other 
cartoons on that basis. The word "speculation" carries no such information 
regarding the work that has gone into it. For example, the various "theories" 
of the evolution of flight are not truly testable to my knowledge, all claims 
of having advanced the "null hypothesis" to the contrary; hence I consider them 
to be cartoons, a word not meant to be derogatory in the slightest. Yes, that 
is what I said, I consider "tree's down, ground up" et al, to be cartoons; 
amenable to ranking but currently untestable, so no way to rise to "null 
hypothesis", or even "hypothesis".

Re cartoon versus speculation -- For instance, a key observation of the 
rodent/dino extinction cartoon (far from best fit, as noted previously) is that 
the highly effective chisel action of rodent teeth provide the talent required 
for a small mammal to efficiently breach a large egg, although I don't know why 
they would, other than their incessant need to gnaw. After watching the 
lion/ostrich egg video, I consider the ability of multituberculates to do the 
same to be highly speculative (also there was a hapless 'possum (American) and 
a goose egg when I was a boy, but I digress ...). The possible coincidence of 
rodent appearance and dino disappearance raise it (barely) to cartoon level. 
Consider it banished to the farthest reaches of cartoon limbo, serving only to 
illustrate the difference between cartoon (an environment, central characters, 
a plot-line, a hook, ...) and a speculation (something that can be made up on 
the spur of the moment about anything
 w/out so much as an accurate observation).

Thanks for inserting the "NOT" in the appropriate place, BTW ... sheesh, I hate 
typos of the 'antithesis kind'. And no K-rodents due to "rodent/lagomorph 
split" is fine w/ me, it was just an example. Which reminds me, does anyone out 
there know the age of the oldest bone (or shell) w/ the characteristic twin 
grooves of rodent teeth? Idle curiosity ...

Don

----- Original Message ---
From: David Marjanovic <david.marjanovic@gmx.at>
To: DML <dinosaur@usc.edu>
Sent: Sunday, November 25, 2007 3:38:03 PM
Subject: Re: attack on dinosaur--horrific video


----- Original Message -----
From: "don ohmes" <d_ohmes@yahoo.com>
Sent: Sunday, November 25, 2007 8:16 PM

> On the extinction side, it is definitely interesting to speculate
 that 
> since rodents probably first appeared near K/Pg, basal rodents may
 have 
> found that incisors were the ideal tool for breaching eggs, and dinos
 (at 
> least some species) may have found the combination of small size and 
> prolificity overwhelming. I don't see it rising to best-fit cartoon 
> status, though, much less falsifiable hypothesis, especially in the 
> (apparent) absence of rodent-gnawed eggshell.

Well, firstly, the rodent-lagomorph split has a nice fossil record in
 the 
Paleocene of Asia, so that I don't see any reason to assume Cretaceous 
rodents. Secondly, you could make the same argument about the 
multituberculates, which had been around since the Late Jurassic, if
 not the 
haramiyids and the tritylodontids, which are as old as the dinosaurs.

> Clarification sidebar -- I don't use "cartoon" here as a derogatory
 term. 
> I try to use it instead of "scenario" in my own musings to make it
 clear 
> that I am NOT advancing a formal hypothesis. In other words, to make
 it 
> clear that I am [NOT] claiming (at that point) testability. Nor do I 
> (obviously) agree w/ the "rule" that testable hypotheses, or
 observations 
> leading thereto, are the only items fit for scientific discussion in
 the 
> realm of 'biospheric history'. In the absence of a testable
 hypothesis, 
> cartoons must be ranked by parsimony (due to the fact
 mutation/selection 
> is the under-lying null), and the most parsimonious receives
 "best-fit" 
> status. [...]

Just call it a speculation, then. 
http://www.dinosauria.com/jdp/evol/evolfact.htm

(Rest of thirteen-kilobyte post snipped.)