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Authors: J. De Visser and C.D.N. Barel

constraints each of the considered parameter value sets can be categorized as optimal, sub- optimal or overruled. The morphospace thus subdivided is called the evaluated morphospace. It demonstrates, for instance, that optimal sets are not randomly distributed in the morphospace but exhibit a certain pattern

In: Netherlands Journal of Zoology

these two inno- vations are calculated and tested. It is shown that sensorial and mechanical requirements for improved probing are mutually exclusive and forces to compromises in construction of the beak tips. The morphospace formulated by this deduction serves as a basis for evolutionary interpretation

In: Netherlands Journal of Zoology

University, Gary, IN 46408-1197, USA) ABSTRACT A morphospace has been developed that connects the ancestral pecking design to filter feeding in birds. The morphospace represents a pattern of transformations in which first surface tension transport of drops along a slightly lengthened and slenderized beak was

In: Netherlands Journal of Zoology

grooming routines actually exhibited by rodents. This result points to a highly structured behavioural morphospace. There are actually very few long routines in the repertoire of rodents, what amounts to saying that there are very few long behavioural sequences that are biologically structured. One could

In: Behaviour

served to visualize distribution of delimitating factors such as species and sexes in morphospace associated with principal components carrying the highest eigenvalues. Mean shape for each valve, sex, and species was created by subdividing the full valve dataset according to sexes and then averaging each

In: Contributions to Zoology

We performed an exploratory analysis of the morphology of the cranium in the white olm (Proteus anguinus anguinus) and the black olm (P. a. parkelj) with micro-CT scanning and geometric morphometrics. The mudpuppy (Necturus maculosus) was used as an outgroup. The black olm falls outside the white olm morphospace by a markedly wider skull, shorter vomers which are positioned further apart and by laterally positioned squamosals and quadrates relative to the palate (the shape of the buccal cavity). On account of its robust skull with more developed premaxillae a shorter otico-occipital region, the black olm is positioned closer to Necturus than are the studied specimens of the white olm. The elongated skull of the white olm, with an anteriorly positioned jaw articulation point, could be regarded as an adaptation for improved feeding success, possibly compensating for lack of vision. As yet, the alternative explanations on the evolution of troglomorphism in Proteus are an extensive convergence in white olms versus the reverse evolution towards less troglomorphic character states in the black olm. To further understand the evolutionary trajectories within Proteus we highlight the following hypotheses for future testing: i) morphological differentiation is smaller within than between genetically differentiated white olm lineages, and ii) ontogenetic shape changes are congruent with the shape changes between lineages. We anticipate that the morphological detail and analytical power that come with the techniques we here employed will assist us in this task.

In: Contributions to Zoology

-231- 10617-3 (paperback). [Also as: ISBN 0-231-10667-X (paper) and 0-231-10666-1 (cloth).] Prices: US$ 60.00 (cloth) or $ 26.50 (paper) in the U.S.A.; US$ 69.00 or £ 48.00 (cloth) and $ 20.50(£ 13.95) for the paperback edition, abroad. Following an introduction to theoretical morphology and morphospace in

In: Crustaceana

, population means of male size and female size, was shown to have reasonable statistical properties and suggested as an appropriate metric for sexual size dimorphism (Smith, 1999 ). Discriminant analysis was used to evaluate the extent of separation between the sexes in the morphospace of characters 1 and

In: Amphibia-Reptilia
Authors: Rob Inkpen and Derek Turner

morphospaces, or multidemnsional spaces in which each dimension represents variation with respect to some morphological trait. 21 One can then think of the evolution of a lineage as tracing a path through such a multidimensional morphospace. 22 Our approach in this paper fits into this tradition of using

In: Journal of the Philosophy of History

Foundation for Statistical Computing, 2012) was used plot RW scores as functions of each other, and Inkscape 0.48.4 (The Inkscape Team) was used to draw minimum convex polygons (MCPs) representing the occupied morphospace for cerci in each ecotype. To visualize the shape variation in the morphospace along

In: Insect Systematics & Evolution