Re: Frills & spills

[Mike Taylor <mike@indexdata.com>]

> Date: Tue, 23 Sep 2003 20:09:35 +1000
> From: zone65@bigpond.com
>
>> Ah! but no Triceratops bonebeds are known (just unsubstaniated
>> rumors). They occur as solitary skeletons (hence
>> individuals). Other ceratopsians (e.g., Monoclonius) do occur in
>> bonebeds. No sweeping generalities about herding can be made.
>
> That is interesting... I wonder why Triceratops would be solitary
> where others would live in herds.

Hi Peter,

First of all, all HP Carpenter said is that it's not been shown that
_Triceratops_ lived in herds; that's very different from saying that
it _has_ been shown that it did _not_ live in herds.  So we are flying
in zero visibility here.  One good strategy might be to bail out :-)

Beyond that -- if _Triceratops_ was indeed solitary -- there is no
possible way to tell _why_ it should be so and _Centrosaurus_ social.
Why are tigers solitary and lions social?  Whatever the reason is, it
certainly won't fossilise; and no more will the reasons for social
behaviour of ceratopsians.

> Apart from the relative size of the animals & their frill/horn
> configurations, what really were the differences among the
> ceratopsians?

Differences are surprisingly few.  Advanced ceratopians (ceratopsids)
fall into two groups: Centrosaurinae and Chasmosaurinae
(=Ceratopsinae).  My understanding is that its pretty much impossible
to tell apart one centrosaur from another from postcranial remains,
and I don't think chasmosaurs vary much between themselves either.
All the fun stuff happens up front on the head.  ((Much the same is
true of the crested lambeosaurines.)

Finally, while I tremble to contradict HP Carpenter ("No sweeping
generalities about herding can be made"), I thought it was the case
that most or maybe even all ceratopsian bonebeds are of centrosaurine
species ... though it's perfectly possible that he knows of chasmosaur
bonebeds that I wot not of.

 _/|_    _______________________________________________________________
/o ) \/  Mike Taylor  <mike@indexdata.com>  http://www.miketaylor.org.uk
)_v__/\  "President Nixon's got a hedgehog called Frank" -- Monty
         Python's Flying Circus, 1st episode

--
Listen to my wife's new CD of kids' music, _Child's Play_, at
        http://www.pipedreaming.org.uk/childsplay/