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RE: Lion & Tigers & Sabre-tooths




In Big Cats & Their Fossil Relatives, I remember mention of possible tiger fossils found in Beringian Alaska (cited from a student thesis on the subject - sorry don't have it to hand so can't help with the name). Both lions and Homotherium were in the area at the time.


Anyone interested in big cats might also be like to check out Monsters of God, which discusses the ecology of both the Gir lions and Siberian tigers.

Steve


Steve White

Tel: +44 (0) 207 564 5033
http://www.gn.apc.org/thunderlizard/index.html

3 Tiffany Court
67 Oakhurst Grove
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SE22 9AG
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>From: dinosaur@usc.edu
>To: Dinosaur Discussion List <dinosaur@usc.edu>
>Subject: DINOSAUR digest 2792
>Date: Wed, 24 Mar 2004 00:04:20 PST
>
>
> DINOSAUR Digest 2792
>
>Topics covered in this issue include:
>
> 1) lions and tigers oh my mistake
> by GSP1954@aol.com
> 2) Those supercrested nyctosaurs
> by david peters <davidrpeters@earthlink.net>
> 3) Re: Those supercrested nyctosaurs
> by Colin McHenry <cmchenry@westserv.net.au>
> 4) Re: Those supercrested nyctosaurs
> by "James R. Cunningham" <jrccea@bellsouth.net>
> 5) Re: Those supercrested fish
> by David Peters <davidrpeters@earthlink.net>
> 6) Re: Those supercrested nyctosaurs
> by "Christopher Collinson" <Chris_Collinson@monarch.net>
> 7) The seal head story
> by Donna Braginetz <quailspg@frii.com>
> 8) Re: lions and tigers oh my mistake
> by Gautam Majumdar <gmajumdar@freeuk.com>
>Date: Tue, 23 Mar 2004 17:23:17 EST
>From: GSP1954@aol.com
>To: dinosaur@usc.edu
>Subject: lions and tigers oh my mistake
>Message-ID: <1dd.1d322cbb.2d9212d5@aol.com>
>MIME-Version: 1.0
>Content-Type: text/plain; charset="US-ASCII"
>Content-Transfer-Encoding: 7bit
>
>Reading more about ligers and tigons found that my claim that lions and
>tigers live together in the Gir forest without interbreeding is incorrect. Only
>lions dwell there. Perhaps because the social lion prides exclude the solitary
>tigers. Would be interesting to know what the interactions were like before the
>lions were hunted out of most of India.
>
>G Paul
>Date: Tue, 23 Mar 2004 16:53:23 -0600 (GMT-06:00)
>From: david peters <davidrpeters@earthlink.net>
>To: dinosaur@usc.edu
>Subject: Those supercrested nyctosaurs
>Message-ID: <4354862.1080082406177.JavaMail.root@huey.psp.pas.earthlink.net>
>Mime-Version: 1.0
>Content-Type: text/plain; charset=us-ascii
>Content-Transfer-Encoding: 7bit
>
>I was surprised to find that in both KJ1 and KJ2 those super crests both acted as super masts to support a very large soft crest, both fore and aft, visible as impressions in the original matrix (now painted over I hear). In addition, both specimens have juveniles associated and in KJ1 much of the rest of the skeleton is impressed. The juvies also have pretty nice little crests.
>
>This will pretty much put to rest any association of gender with crest size or hip shape.
>
>I don't know how these crests worked aerodynamically. Suffice it to say the sailfish is the fastest of all fish and no one (to my knowledge) has tested the theory behind the practice. Any ref. help here would be gratefully appreciated.
>
>I'll show all this and the rest in Denver at the SVP convention in October. It'll be a good show.
>
>David Peters
>St. Louis
>
>PS. Sorry for the absence. I took a vacation following Phil Bigelow's query.
>
>
>
>
>
>
>
>Date: Wed, 24 Mar 2004 11:44:20 +1100
>From: Colin McHenry <cmchenry@westserv.net.au>
>To: david peters <davidrpeters@earthlink.net>, DML <dinosaur@usc.edu>
>Subject: Re: Those supercrested nyctosaurs
>Message-ID: <002601c41139$26fed720$0d209486@HeartofGold>
>MIME-version: 1.0
>Content-type: text/plain; charset=iso-8859-1
>Content-transfer-encoding: 7BIT
>
>
>
> > I was surprised to find that in both KJ1 and KJ2 those super crests both
>acted as super masts to support a very large soft crest, both fore and aft,
>visible as impressions in the original matrix (now painted over I hear). In
>addition, both specimens have juveniles associated and in KJ1 much of the
>rest of the skeleton is impressed. The juvies also have pretty nice little
>crests.
> >
> > This will pretty much put to rest any association of gender with crest
>size or hip shape.
> >
> > I don't know how these crests worked aerodynamically. Suffice it to say
>the sailfish is the fastest of all fish and no one (to my knowledge) has
>tested the theory behind the practice. Any ref. help here would be
>gratefully appreciated.
>
>
>Conway, Cunningham, Gerritsen, and McHenry presented an aerodynamic model
>for Nyctosaurus, based upon KJ1 & 2, at CAVEPS last year. The presence of
>a membrane was assumed, based upon the superficial similarity of the crest
>to the mast and boom of a sailboard, and following an earlier suggestion by
>Dino Frey. Preliminary calculations suggested that the hypothetical
>membrane could have acted like a sail during low level flight, as long as
>there was contact between the animal and the water surface sufficient to
>resist the leeway (sideways horizontal force) caused by the action of the
>wind upon the 'sail'. Such contact could have come from the mandibe during
>skim feeding, or from e.g. the wing. At windspeeds between 6 and 9 knots
>our model is calculated to make reasonable progress over the water. Climate
>simulations of the WIB during the middle Cretaceous suggest that these
>speeds would have been within the normal range of expected windspeeds.
>
>Of course, whether or not our model has any relevance to what Nyctosaurus
>was actually doing is unknown. One problem facing any future work on this
>topic is that the specimens are not in a public collection.
>
>I'm not sure how the sailfish is relevant to our model of 'sail assisted
>gliding' in Nyctosaurus. During rapid swimming the sail on the sailfish is
>retracted into a longitudinal groove that runs along the back, similar to
>the recesses for the paired fins in this and other tunniforms. See the
>appropriate episode of 'The Blue Planet' for footage of this.
>
>Cheers
>Col
>
>
>Date: Tue, 23 Mar 2004 21:26:16 -0800
>From: "James R. Cunningham" <jrccea@bellsouth.net>
>To: cmchenry@westserv.net.au, dinosaur@usc.edu, margootjeg@yahoo.com
>Subject: Re: Those supercrested nyctosaurs
>Message-ID: <40611BF8.2E66154E@bellsouth.net>
>MIME-Version: 1.0
>Content-Type: text/plain; charset=us-ascii
>Content-Transfer-Encoding: 7bit
>
>Colin McHenry wrote:
>
> > Conway, Cunningham, Gerritsen, and McHenry presented an aerodynamic model
> > for Nyctosaurus, based upon KJ1 & 2, at CAVEPS last year. The presence of
> > a membrane was assumed, based upon the superficial similarity of the crest
> > to the mast and boom of a sailboard, and following an earlier suggestion by
> > Dino Frey.
>
>Actually, in my mind we were careful not to assert a belief in the actual
>presence of a membraned crest. We were interested in what effects such a
>membrane crest might have if it were actually present; if it could be viable
>and have some beneficial effects on bioenergetics. Our initial work suggested
>that under some circumstances it could indeed be beneficial so long as an
>appropriate part of the animal was in contact with the water most of the time.
>However, in order not to present a biased perspective, one of the images that we
>present with our talks on the KJ specimens is an alternative antlered version of
>the beast. Personally I do not think there is strong evidence for or against a
>membrane crested Nyctosaurus. But the benefits are substantial enough that
>further work is warranted on the concept, both on the benefits and on the
>problems presented by a membrane crest.
>
> > Preliminary calculations suggested that the hypothetical
> > membrane could have acted like a sail during low level flight, as long as
> > there was contact between the animal and the water surface sufficient to
> > resist the leeway (sideways horizontal force) caused by the action of the
> > wind upon the 'sail'. Such contact could have come from the mandibe during
> > skim feeding, or from e.g. the wing. At windspeeds between 6 and 9 knots
> > our model is calculated to make reasonable progress over the water. Climate
> > simulations of the WIB during the middle Cretaceous suggest that these
> > speeds would have been within the normal range of expected windspeeds.
> >
> > Of course, whether or not our model has any relevance to what Nyctosaurus
> > was actually doing is unknown. One problem facing any future work on this
> > topic is that the specimens are not in a public collection.
>
>Date: Tue, 23 Mar 2004 22:05:26 -0600
>From: David Peters <davidrpeters@earthlink.net>
>To: Colin McHenry <cmchenry@westserv.net.au>
>Cc: DML <dinosaur@usc.edu>
>Subject: Re: Those supercrested fish
>Message-ID: <40610906.62BE90EC@earthlink.net>
>MIME-Version: 1.0
>Content-Type: text/plain; charset=us-ascii; x-mac-type="54455854"; x-mac-creator="4D4F5353"
>Content-Transfer-Encoding: 7bit
>
> > I'm not sure how the sailfish is relevant to our model of 'sail assisted
> > gliding' in Nyctosaurus. During rapid swimming the sail on the sailfish is
> > retracted into a longitudinal groove that runs along the back, similar to
> > the recesses for the paired fins in this and other tunniforms. See the
> > appropriate episode of 'The Blue Planet' for footage of this.
> >
> > Cheers
> > Col
>
>Check.
>
>Still, there are plenty of times in which forward movement takes place with the
>sail erect without too much ill effect.
>
>On the same thought... In airplanes jamming the rudder pedal to the floor
>doesn't affect turning right away, but it does affect drag and slows the
>aircraft by presenting the broadside of the aircraft to the airstream. Perhaps
>the sail acts as an efficient brake for the fastest fish in the sea.
>
>DP
>
>
>
>Date: Tue, 23 Mar 2004 20:25:52 -0800
>From: "Christopher Collinson" <Chris_Collinson@monarch.net>
>To: <dinosaur@usc.edu>
>Subject: Re: Those supercrested nyctosaurs
>Message-ID: <000f01c41158$1b9413e0$5245f418@monarch.net>
>MIME-Version: 1.0
>Content-Type: text/plain;
> charset="iso-8859-1"
>Content-Transfer-Encoding: 7bit
>
>
>----- Original Message -----
>From: "James R. Cunningham" <jrccea@bellsouth.net>
>To: <cmchenry@westserv.net.au>; <dinosaur@usc.edu>; <margootjeg@yahoo.com>
>Sent: Tuesday, March 23, 2004 9:26 PM
>Subject: Re: Those supercrested nyctosaurs
>
>
> >Our initial work suggested
> > that under some circumstances it could indeed be beneficial so long as an
> > appropriate part of the animal was in contact with the water most of the
>time.
>
>Ok, so what happens if there is no contact with the sea? The surface of the
>ocean is extremely dynamic and with the swells and all I would assume that
>at some point the contact between animal and water will be broken, for
>however briefly. And that's just when sailing. There must also have been
>occasions when the animal was not actively using its crest to sail. How does
>the sail crest affect the pterosaur's performance in these cases?
>
>Cheers,
>Christopher Collinson.
>
>
>
>Date: Tue, 23 Mar 2004 23:50:47 -0700
>From: Donna Braginetz <quailspg@frii.com>
>To: DML <dinosaur@usc.edu>
>Subject: The seal head story
>Message-ID: <40612FC4.174D69FE@frii.com>
>MIME-Version: 1.0
>Content-Type: text/plain; charset=us-ascii
>Content-Transfer-Encoding: 7bit
>
>LISTERS -
>
>If you haven't already heard the story, go here
>
>http://www.ananova.com/news/story/sm_898699.html?menu=news.quirkies
>
>for a cautionary tale: "Man tried to board plane with severed seal's head."
>
>A sobering reminder for folks who like to indulge in a little scientific
>scavenging now and then...
>
>- DONNA BRAGINETZ
>Date: Wed, 24 Mar 2004 07:00:59 +0000
>From: Gautam Majumdar <gmajumdar@freeuk.com>
>To: DML <Dinosaur@usc.edu>
>Subject: Re: lions and tigers oh my mistake
>Message-ID: <200403240700.59758.gmajumdar@freeuk.com>
>MIME-Version: 1.0
>Content-Type: text/plain;
> charset="iso-8859-1"
>Content-Transfer-Encoding: 7bit
>Content-Disposition: inline
>
>On Tuesday 23 Mar 2004 10:23 pm, GSP1954@aol.com wrote:
> > Reading more about ligers and tigons found that my claim that lions
> > and tigers live together in the Gir forest without interbreeding is
> > incorrect. Only lions dwell there. Perhaps because the social lion
> > prides exclude the solitary tigers. Would be interesting to know what
> > the interactions were like before the lions were hunted out of most
> > of India.
> >
>Lions and tigers probably never lived in the same habitat in India.
>Lions prefer an open habitat. The Gir forest is not a dense forest with
>undergrowth. It is a semi-arid region with trees but not much ground
>cover with bushes. Tigers love "jungle", i.e., areas with dense
>undergrowth in which they can hide. The hunting habit of the tiger,
>solitary ambush technique, would be quite inappropriate in the Gir
>forest or similar habitat.
>
>--
>
>Gautam Majumdar
>
>Please send e-mails to gmajumdar@freeuk.com
>


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