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Re: sauropod behaviour speculations



BRIEF REPLY: Your points are well-taken, Jaime, and
Matthew Carrano's research is used throughout my own
interpolative book-in-progress. However, without
repeating myself, I insist that ongoing behavioural
strategies of observable taxa are excellent sources of
extrapolation. The mammalian taxa, of course, are not
dinosaurs, but the extant theropods ("birds") are
highly derived lineages, flying and secondarily
flightless, whose morphologies are not what one can
use. Thus, we turn to the mammalian megaherbivores who
are in similar  econiches to the pre-K/T dinosaurs for
hints, so to speak, of probable parameters of
behavioural systems. I do not believe, e.g., that
waddling ankylosaurs are mirror images of later
armoured mammalians, or that elephant/giraffe are
mirror images of sauropods. However: the
elephant/giraffe, when one combines data of
morphogenesis and cardiovascular systems, do give one
analytic tools. You ask: "what small sauropods in what
habitats?" Well, consider: when hatched a sauropod is
not full-grown, and a small sauropod may have adapted
certain strategies of behaviour not needed when a
multi-tonne adult.
*******************************************************
--- "Jaime A. Headden" <qilongia@yahoo.com> wrote:
> Stephan Pickering (stefanpickering2002@yahoo.com)
> wrote:
> 
> <Both investigations should be studied with care and
> open-mindedness, as I
> believe (contra the opinions of some) that ungulates
> might provide one
> with interesting ecological templates which might,
> just might, give one an
> inferred glimpse, a possible interpolative
> framework, of how small
> sauropod taxa may have been behaving near lakes and
> rivers.>
> 
>   You shouldn't misinterpret anything _I_ might say;
> I simply ask that
> speculations of the behavior of extinct animals
> follow in trajectories
> that can be tested for them, not simply inferred
> from a set of fluffy,
> extant birds, and especially more difficult in the
> form of furry extant
> cynodonts. Without testing, this is nothing idle
> banter on why
> *Cetiosaurus* shouldn't be depicted as an
> infanticidal, matriarchal beast
> when we lack evidence of babies, parental care, or
> even gender in pretty
> much any [extinct] dinosaur, save the probably
> allocation of some
> long-tailed specimens to males in *Confuciusornis*
> and probably
> *Protopteryx* as well (among birds only, however; no
> non-avian dinosaur is
> known to gender, just sexual dimorphism). However,
> this is off the topic I
> am responding to. To understand exactly how far one
> can take the
> ungulate/dinosaur analogue, Matt Carrano has worked
> on several papers that
> draw attention to this data, both critically and
> optimistically (if you
> prefer). He comes down on the side of being able to
> use extant data to
> look at extinct, non-related species, but its clear
> from these papers
> exactly what you can do with that data, rather than
> what you want to do
> with what you're looking at. It may seem a pretty,
> involved structure to
> give dinosaurs all these behaviors, inferred from
> elephants and pigs and
> the like, for sauropods surely could have had
> irridescent integument a là
> hummingbirds and Bakker, but its one of those things
> that can only be
> solved with a time machine.
> 
>   Carrano, M.T. 1998. Locomotion in non-avian
> dinosaurs: integrating data
>   from hindlimb kinematics, in vivo strains, and
> bone morphology.
>   _Paleobiology_ 24 (4): 450-469.
> 
>   Carrano, M.T. 1999. What, if anything, is a
> cursor? Categories vs.
>   continuua for determining locomotor habit in
> mammals and
>   dinosaurs._Journal of Zoology, London_ 247: 29-42.
> 
>   Carrano, M.T.; Janis, C.M.; and Sepkoski, J.J.,
> Jr. 1999. Hadrosaurs as
>   ungulate parallels: Lost lifestyles and deficient
> data. _Acta
>   Palaeontologica Polonica_ 44 (3): 237-261.
> 
>   Carrano, M.T. 2000. Homoplasy and the evolution of
> dinosaur locomotion.
>   _Palaeobiology_ 26: 489-512.
> 
>   Carrano, M.T. 2001. Implications of limb bone
> scaling, curvature and
>   eccentricity in mammals and non-avian dinosaurs.
> _Journal of Zoology,
>   London_ 254: 41-55. 
> 
>   His own thesis goes into more broad explanations
> that much of his recent
> work is the publication of:
> 
>   Carrano, M.T. (1998) The evolution of dinosaur
> locomotion: Functional
>   morphology, biomechanics, and modern analogs.
> Ph.D. dissertation,
>   University of Chicago, 1-424 [in 2 vols.].
> 
>   So asdie from all this:
> 
>   What small sauropods in which habitats? The only
> dwarf sauropods known
> were found in an island system in Europe, whereas
> baby sauropods were
> likely constrained by the locomotion and reach of
> their much older (and
> larger) relatives. Tracks show mud-walking, and
> such, as well as shallow
> coastal hand-prints that suggest a swimming style,
> but these are
> mechanical in nature and do not tell us about the
> behavior of these
> animals.
> 
>   Cheers,
> 
> =====
> Jaime A. Headden
> 
>   Little steps are often the hardest to take.  We
> are too used to making leaps in the face of
> adversity, that a simple skip is so hard to do.  We
> should all learn to walk soft, walk small, see the
> world around us rather than zoom by it.
> 
> "Innocent, unbiased observation is a myth." --- P.B.
> Medawar (1969)
> 
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