[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

SQUAMATES & CHORISTODERES, LIVEZEY, CROCS & CATS



Hey everyone. At the risk of sending a post that is concerned with 
something other than the philosophy of cladistics, biogeography or 
geological dating, here are some new refs I picked up.

New choristoderes, quite possibly among the most enigmatic of all 
diapsids...

GAO, K. and FOX, R.C. 1998. New choristoderes (Reptilia: Diapsida) 
from the Upper Cretaceous and Palaeocene, Alberta and Saskatchewan, 
Canada, and phylogenetic relationships of Choristodera. _Zool. J. 
Linn. Soc._ 124: 303-353.

Choristoderes are weird, with a weird fossil record. _Cteniogenys_ is 
extended (from the Jurassic) into the Upper Cretaceous Oldman Fm. in 
this paper; there's also Canada's first _Simoedosaurus_ and a new 
species of _Champsosaurus_. 'New information about Asian 
choristoderes supports..' a new (heterodox) phylogeny.  There's 
something very odd about choristoderes that allows them to uncannily 
dodge the fossil record. Gao and Fox argue that the group occupies a 
basal position within Diapsida, and may be outside of Younginiformes 
+ Sauria. See?

Squamates...

EVANS, S.E. and BARBADILLO, L.J. 1998. An unusual lizard (Reptilia: 
Squamata) from the Early Cretaceous of Las Hoyas, Spain. _Zool. J. 
Linn. Soc._ 124: 235-265.

The new taxon _Scandensia ciervensis_ is a very odd, apparently 
scansorial/aboreal basal squamate. The thing is outside of Iguania + 
Scleroglossa (like _Huehuecuetzpalli_) so is it really a lizard?:) 
Astute readers will note that the new taxon's generic name is only 
one letter away from the name given to tree shrews (Scandentia).

LEE, M.S.Y. 1998. Convergent evolution and character correlation in 
burrowing reptiles: towards a resolution of squamate relationships. 
_Biol. J. Linn. Soc. _ 65: 369-453.

Covers in detail the controversy over snake relationships: concludes 
that they are anguimorphs allied to mosasauroids and varanids. What's 
cool, and will be of real interest to you cladophiles, is that when 
fossil taxa are ignored, snakes switch in the squamate tree to become 
allied with amphisbaenians and dibamids. In fact, without the 
fossils, this group forms a well-corroborated clade. The moral is 
INCLUDE AS MANY TAXA AS POSSIBLE (I think) and, oh yes, don't forget 
the fossils! Mike also asserts that _Pachyrhachis_ is a basal snake, 
and not an advanced one as recently argued by Hassem Zaher (1998).

For people into volant theropods, the long awaited...

LIVEZEY, B. 1998. A phylogenetic analysis of the Gruiformes (Aves) 
based on morphological characters, with an emphasis on the rails 
(Rallidae). _Phil. Trans. R. Soc._ B 353: 2077-2151.

Livezey finds Gruiformes to be monophyletic (contra Stresemann, 
Lowe, Houde, Olson and numerous other workers: gruiforms have long 
been a problematic assemblance and different members have been 
variously affiliated with all kinds of other birds). Big cladistic 
analysis - 20 000 trees were generated - and Grues (psophiids, 
aramids, gruids, heliornithids and rallids) is monophyletic. 
Pedionomids and turnicids are apparently sister taxa outside of 
Gruiformes, while, surprise surprise, cariamids and phorusrhacoids 
form a clade. 

Also on archosaurs, the paper on croc thermoregulation is..

SEEBACHER, F., GRIGG, G.C. and BEARD, L.A. 1998. Crocodiles as 
dinosaurs: behavioural thermoregulation in very large ectotherms 
leads to high and stable body temperatures. _J. Experimental Biology_ 
202: 77-86.

Finally, shouldn't be mentioned here but I'll try my luck anyway, 
some very interesting new stuff on cats (for Beri and Steve)..

FUNSTON, P.J., MILLS, M.G.L., BIGGS, H.C. and RICHARDSON, P.R.K. 
1998. Hunting by male lions: ecological influences and 
socioecological implications. _Animal Behaviour_ 56: 1333-1345.

In this study (Kruger), dubbed 'the most intensive to date of male 
lion ecology', male lions were active hunters - not scavengers - and 
preyed predominantly on _Syncerus_! This is must read for anyone 
interested in carnivoran behaviour and ecology.

ANTON, M., GARCIA-PEREA, R. and TURNER, A. 1998. Reconstructed facial 
appearance of the sabretoothed felid _Smilodon_. _Zool. J. Linn. 
Soc._ 124: 369-386.

Again, a must read for anyone interested in reconstructed fossil 
carnivorans. The authors argue that Miller's (1969) famous 
reconstruction of _Smilodon_ does not stand up on the basis of EPB 
and functional morphology, and the real _Smilodon_ was far more like 
pantherines in appearance. Yes Steve, a copy is on the way.

"I thought I told you to stay on the command ship"

DARREN NAISH
darren.naish@port.ac.uk