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G. Mayr (2008) Avian higher-level phylogeny:
well-supported clades and what we can learn from a
phylogenetic analysis of 2954 morphological characters
Journal of Zoological Systematics and Evolutionary
Research 46 (1) , 63?72

ABSTRACT ? It has been shown that increased character
sampling betters the accuracy of phylogenetic
reconstructions in the case of molecular data. A
recently published analysis of avian higher-level
phylogenetics based on 2954 morphological characters
now provides an empirical example to test whether this
is also true in the case of morphological characters.
Several clades are discussed which are supported by
multiple analyses of mutually independent molecular
data (sequences of nuclear genes on different
chromosomes and mitochondrial genes) as well as
morphological apomorphies, but did not result from
parsimony analysis of the large morphological data
set. Incorrect character scorings in that analysis
notwithstanding, it is concluded that in the case of
morphological data, increased character sampling does
not necessarily better the accuracy of a
phylogenetic reconstruction. Because morphological
characters usually have a strongly varying complexity,
many simple and homoplastic characters may overrule
fewer ones of greater phylogenetic significance
in large data sets, thus producing a low ratio of
phylogenetic signal to "noise" in the data.


Castro et al. (2007) Sauropods of the Itapecuru Group
(Lower/Middle Albian), São Luís-Grajaú Basin, Maranhão
State, Brazil. Revista brasileira de paleontologia
10(3):195-200, Setembro/Dezembro 2007

ABSTRACT ? In this paper, new sauropod remains from
the lower/middle Albian of the Itapecuru Group, São
Grajaú Basin, Maranhão State (Brazil) are described.
The material comprises vertebral centra, fragments of
neural arches and a fragment of the proximal end of a
humerus of limited diagnostic value. Morphological
analyses of these elements indicate the presence of
titanosaur sauropods and taxa related to the
Rebbachisauridae. Sauropods are documented in the
lower/middle Albian deposits assigned to the
?Undifferentiated Unit? for the first time. Previous
occurrences of these herbivores are known from
Cenomanian rocks of the Alcântara Formation, which
overlays the Undifferentiated Unit. Although
fragmentary, the reported fossils extend the record of
sauropods in Brazilian Cretaceous deposits.


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