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Re: Archosaur antics--world's only playful "pet" crocodile dies



From: Ben Creisler
bh480@scn.org
 
Historically, it appears that ancient Egyptians kept and mummified "pet"
crocodiles for religious purposes that now turn out to be the distinct
species Crocodylus suchus. Previously, modern zoologists treated this
crocodile as a synonym of the more aggressive Crocodilus niloticus.

Apparently this recent research has not been mentioned yet on the DML. The
pdfs are free. 


EVON HEKKALA, MATTHEW H. SHIRLEY, GEORGE AMATO, JAMES D. AUSTIN, SUELLEN
CHARTER, JOHN THORBJARNARSON, KENT A. VLIET, MARLYS L. HOUCK, ROB DESALLE
and MICHAEL J. BLUM (2011)
An ancient icon reveals new mysteries: mummy DNA resurrects a cryptic
species within the Nile crocodile. 
Molecular Ecology 20(20): 4199?4215
DOI: 10.1111/j.1365-294X.2011.05245.x
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-294X.2011.05245.x/abstract
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-294X.2011.05245.x/pdf


The Nile crocodile (Crocodylus niloticus) is an ancient icon of both
cultural and scientific interest. The species is emblematic of the great
civilizations of the Nile River valley and serves as a model for
international wildlife conservation. Despite its familiarity, a
centuries-long dispute over the taxonomic status of the Nile crocodile
remains unresolved. This dispute not only confounds our understanding of
the origins and biogeography of the ?true crocodiles? of the crown genus
Crocodylus, but also complicates conservation and management of this
commercially valuable species. We have taken a total evidence approach
involving phylogenetic analysis of mitochondrial and nuclear markers, as
well as karyotype analysis of chromosome number and structure, to assess
the monophyletic status of the Nile crocodile. Samples were collected from
throughout Africa, covering all major bioregions. We also utilized
specimens from museum collections, including mummified crocodiles from the
ancient Egyptian temples at Thebes and the Grottes de Samoun, to
reconstruct the genetic profiles of extirpated populations. Our analyses
reveal a cryptic evolutionary lineage within the Nile crocodile that
elucidates the biogeographic history of the genus and clarifies
long-standing arguments over the species? taxonomic identity and
conservation status. An examination of crocodile mummy haplotypes indicates
that the cryptic lineage corresponds to an earlier description of C. suchus
and suggests that both African Crocodylus lineages historically inhabited
the Nile River. Recent survey efforts indicate that C. suchus is declining
or extirpated throughout much of its distribution. Without proper
recognition of this cryptic species, current sustainable use-based
management policies for the Nile crocodile may do more harm than good.



M. T. P. GILBERT  (2011)
The mummy returns? and sheds new light on old questions.
Molecular Ecology 20(20): 4195?4198
DOI: 10.1111/j.1365-294X.2011.05265.x
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-294X.2011.05265.x/abstract
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-294X.2011.05265.x/pdf


Whether as the ancient Egyptian crocodile-god Sobek, a terrifying predator
of African waterways, or simply as a premium handbag leather, the Nile
crocodile (Crocodylus niloticus) has long held the fascination of mankind.
Despite 200 years of study, however, uncertainty remains as to its
taxonomy. While resolving such issues are key to understanding the origins
and biogeography of the so-called true crocodiles of genus Crocodylus,
given widespread ongoing range contraction, such issues are paramount for
design of future conservation strategies. In this issue of Molecular
Ecology, Hekkala et al. (2011) apply analysis of modern, historic and
ancient DNA (aDNA) to the questions, with far-reaching implications. First
they demonstrate that, as currently described, the Nile crocodile is
paraphyletic, with individuals from the east and western clades separated
by a number of New World crocodile species. The consequences of this
finding are as important for conservation efforts as for their impact on
crocodile taxonomy. Furthermore, they strike at the heart of the
long-standing debate over whether aDNA analysis of ancient Egyptian mummies
is scientifically sound.


New stories:
Nile crocodile is two species
http://www.nature.com/news/2011/110914/full/news.2011.535.html

http://www.physorg.com/news/2011-09-nile-crocodile-species.html

http://blogs.discovermagazine.com/notrocketscience/2011/09/14/nile-crocodile
-is-actually-two-species-and-the-egyptians-knew-it/?utm_source=feedburner&ut
m_medium=feed&utm_campaign=Feed%3A+NotRocketScience+%28Not+Exactly+Rocket+Sc
ience%29



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