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| Registros recuperados: 176 | |
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| Schockaert, E.R.. |
| Possible evolutionary trends within Polycystididae have been indicated by Karling (1956) while studying the male genital organs of seyeral turbellarian groups. For the moment his ideas seem the most valuable basis for establishing an intrafamiliar system of Polycystididae, and have hence been applied formally (Schockaert, 1974). However, it can be demonstrated with several examples that the underlying principles prove to be unsatisfactory when one tries to apply Hennig's methodology:-the subfamily Duplacrorhynchinae Schockaert & Karling, 1970, can be recognized as containing the most plesimorph polycystidids; a synapomorph character that would give us an indication of the monophyly of this taxon is lacking;-the homology of some glandular elements (al!... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Evolution; Taxonomy; Polycystididae; Turbellaria [Flatworms]. |
| Ano: 1977 |
URL: http://www.vliz.be/imisdocs/publications/238823.pdf |
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| Hammen, L. van der. |
| A comparative study is made of the three groups (Cyphophthalmi, Laniatores and Palpatores) into which Opilionida are currently subdivided. Methods, principles and terminology, adopted in this paper, correspond with those of parts I and II of the present series of studies in Chelicerata. Special attention is paid to mouthparts and appendages, to opilionid relationships, and to the evolution of chelicerate characters. It is demonstrated that Cyphophthalmi present all the essential opilionid characters, and evidently do not constitute a separate group. It is also demonstrated that Opilionida are not closely related to Actinotrichid or Anactinotrichid mites, but to other groups with a so-called myliosoma (mouthparts associated with coxisternal feeding); these... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Opilionida; Chelicerata; Comparative morphology; Classification; Evolution; Phy- logeny.; 42.74. |
| Ano: 1985 |
URL: http://www.repository.naturalis.nl/record/317785 |
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| Hammen, L. van der. |
| A comparative study is made of four chelicerate classes: Apatellata (Solifugae and Pseudoscorpionida), Arachnida s. str. (both groups of Uropygi, i.e. Holopeltida and Schizomida, Amblypygi and Araneida), Scorpionida and Xiphosura. Methods, principles and terminology, adopted in this paper, correspond with those of parts I -111 of the present series of comparative studies in Chelicerata. Special attention is paid to segmentation of the body, respiratory organs, orifices of coxal glands, mouthparts, and appendages. The evolution of these structures is studied, and the relationships of the chelicerate classes and subclasses are reinvestigated and discussed. |
| Tipo: Article / Letter to the editor |
Palavras-chave: Amblypygi; Apatellata; Arachnida; Araneida; Chelicerata; Evolution; Holopeltida; Morphology; Pseudoscorpionida; Schizomida; Scorpionida; Solifugae; Uropygi; Xiphosura.; 42.74. |
| Ano: 1986 |
URL: http://www.repository.naturalis.nl/record/317847 |
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| Ouboter, P.E.. |
| Of the genus Scincella Mittleman, 1950 (sensu Greer, 1974) 337 specimens from Asia were examined for 74 characters, which were treated in a numerical-taxonomic way. The dendrogram resulting from this analysis was not stringently adhered to. Because of the wide variation in certain numerical scale characters within one taxon or even within one population, these characters (used by many authors as key characters to separate taxa) are not regarded as very important. For sympatric and parapatric species other characters, including relative size of head, body and limbs, are regarded as very important, because these characters are influenced by the way of life (niche separation). For the separation of allopatric species scale-numbers, but many other characters... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Scincidae; Scincella; Keys; New species; Numerical analysis; Evolution; Asia; Zoogeography.; 42.82. |
| Ano: 1986 |
URL: http://www.repository.naturalis.nl/record/317820 |
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| Woltz,Ph; Gajardo,R; Ferreira,A.G. |
| The anatomy of 112 species out of the 184 at present recognized is compared. The evolutionary sequence proposed shows in several different "series" the passage by successive transformations from an ancestral type with short one-nerved leaves, well-developed sub-epidermis and many resin canals to those with long wide leaves, first one-nerved then several-nerved, with reduced sub-epidermis and few resin canals. An over-evolved condition sometimes produces at the end of a "série" an apparent reversion to the ancestral type: leaves short or reduced to fleshy scales with late proliferation of canals separated in the mesophyll. A striking correlation between foliar anatomy and geographic latitude suggests, as with vascular evolution in seedlings at the cotyledon... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Podocarpineae; Evolution; Anatomy comparative. |
| Ano: 1987 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33061987000200002 |
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| Wägele, Johann-Wolfgang. |
| The evolution of the stygobiontic isopods is discussed correlating the phylogenetic system with biogeography. All stygobiontic isopods probably are derived from remote marine ancestors. The colonization of subterranean aquatic biotopes occurred in two ways: (1) via the coastal groundwater in the case of the Microparasellidae, Gnathostenetroididae, Stenetriidae, and in Cyathura (Stygocyathura), (2) in most families, however, via epigean freshwater ancestors. Ancient freshwater isopods that must already have existed before the Cretaceous and whose stygobiontic phylogenetic lines partly must have existed before the opening of the Atlantic are the Aselloidea, Calabozoida, Phreatoicidea, and probably also the Protojaniridae. In the course of Cretaceous and... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Crustacea; Isopoda; Evolution; Stygofauna; Biogeography. |
| Ano: 1990 |
URL: http://www.repository.naturalis.nl/record/504433 |
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| Dekker, R.W.R.J.; Brom, T.G.. |
| Among megapodes, several incubation stategies can be recognized. Eggs are incubated by heat generated from microbial decomposition, volcanism, or the sun. For a long time, controversy has existed whether these strategies represent primitive traits, inherited from reptilian ancestors, or have evolved from the 'regular' way of incubation in birds. In this paper these strategies are interpreted by superimposing them on the most recent phylogenetic hypotheses regarding the inter- and intrafamilial relationships of megapodes. We conclude that similarities shared with reptiles and kiwis are due to convergence. Arguments are put forward that mound-building represents the plesiomorphic condition in megapodes and that burrow-nesting has been derived from it.... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Megapodiidae; Incubation-strategies; Evolution; Apterygidae.; 42.83. |
| Ano: 1992 |
URL: http://www.repository.naturalis.nl/record/317761 |
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| Ćurčić, Božidar P.M.; Poinar, George O.; Sarbu, Serban M.. |
| Two species of Roncus L. Koch, 1873 (Neobisiidae), new to science (R. ciobanmos n. sp. and R. dragobete n. sp.), and one species of Neobisium Chamberlin, 1930 [N. (N). biharicum Beier, 1939], collected in the Movile Cave, southern Dobrogea, Romania, have been described, diagnostic characters illustrated, and their geographic distribution analyzed. In addition, the description of Chthonius (Chthonius) monicae Boghean, 1989 (Chthoniidae), otherwise known only from two females, has been amended. The possible relationships of these species are discussed in view of the importance of some diagnostic characters and of the evolution of their cave habitat. |
| Tipo: Article / Letter to the editor |
Palavras-chave: Cave fauna; Taxonomy; Biogeography; Evolution; Pseudoscorpions; Chthoniidae; Neobisiidae; Chthonius; Roncus; Neobisium; New species. |
| Ano: 1994 |
URL: http://www.repository.naturalis.nl/record/504604 |
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| Sanz, Sebastián; Platvoet, Dirk. |
| On several occasions, shrimps belonging to a new species of the genus Typhlatya were collected in a cave in the province of Castellón, Spain. This is the first record of the genus in the Iberian Peninsula. The species is described and the validity, distribution, and zoogeography of the genus, as well as the status of the genus Spelaeocaris, are discussed. Former models for the evolution of the genus Typhlatya and its genus group are reviewed, as well as the system of inner classification of the Atyidae and its biogeographical meaning. For the age and evolution of the genus we developed a new model based on vicariance principles that involves further evolution of each species after the disruption of the ancestral range. This allows new estimations for the... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Typhlatya; Decapoda; Spain; Subterranean waters; Systematics; Zoogeography; Vicariance; Evolution; Key to genus. |
| Ano: 1995 |
URL: http://www.repository.naturalis.nl/record/503881 |
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| Fiers, Frank; Reid, Janet W.; Iliffe, Thomas M.; Suárez-Morales, Eduardo. |
| Four previously unknown hypogean species of cyclopoid copepods were collected in cenotes and wells of the Yucatán Peninsula, Mexico. Diacyclops chakan sp. n. and D. puuc sp. n. differ from their congeners in combining 3-segmented swimming legs, 11-segmented antennules, and legs 1-4 endopodite segment 2 all with 2 setae. Species of Diacyclops rarely occur in tropical regions, and the Diacyclops described here are only the second and third species recorded from Mexico. The benthic D. puuc was found in the large underground reservoir of a cenote. Diacyclops chakan was encountered in such large open subterranean water basins, but more frequently and abundantly in wells. The two Mesocyclops species, M. chaci sp. n. and M. yutsil sp. n., most closely resemble... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Diacyclops; Mesocyclops; Copepoda; Cyclopoida; Biogeography; Evolution; Hypogean; Karst; Species-flock; Taxonomy; Mexico. |
| Ano: 1996 |
URL: http://www.repository.naturalis.nl/record/504240 |
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| Circadian organization means the way in which the entire circadian system above the cellular level is put together physically and the principles and rules that determine the interactions among its component parts which produce overt rhythms of physiology and behavior. Understanding this organization and its evolution is of practical importance as well as of basic interest. The first major problem that we face is the difficulty of making sense of the apparently great diversity that we observe in circadian organization of diverse vertebrates. Some of this diversity falls neatly into place along phylogenetic lines leading to firm generalizations: i) in all vertebrates there is a "circadian axis" consisting of the retinas, the pineal gland and the... |
| Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Circadian rhythms; Evolution; Vertebrates; Pineal; SCN; Retina; Melatonin. |
| Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000300003 |
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| Mooers, Arne Ø.; Schluter, Dolph. |
| How do traits change through time and with speciation? We present a simple and generally applicable method for comparing various models of the macroevolution of traits within a maximum likelihood framework. We illustrate four such models: 1) variance among species accumulates in direct proportion to time separating them (gradual model); 2) variation accumulates with the number of speciation events separating them (speciational model); 3) differences between species are unrelated to phylogenetic relatedness (pitchfork model); and 4) a free model where the trait evolves at its own idiosyncratic rate among lineages. Using species-specific body size, we compare the four models across two data sets: twenty-one clades of vertebrate species, and two clades of... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Brownian motion; Macroevolution; Maximum likelihood; Phylogenies; Vertebrate body size; Evolution. |
| Ano: 1998 |
URL: http://www.repository.naturalis.nl/record/534379 |
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| MATURANA-ROMESIN,HUMBERTO; MPODOZIS,JORGE. |
| In this article we propose that the mechanism that gave rise to the diversity of living systems that we find today, as well as to the biosphere as coherent system of interrelated autonomous living systems, is natural drift. And we also propose that that which we biologists connote with the expression natural selection is a consequence of the history of the constitution of the biosphere through natural drift, and not the mechanism that generates that history. Moreover, we do this by proposing: a) that the history of living systems on earth is the history of the arising, conservation, and diversification of lineages through reproduction, and not of populations; b) that biological reproduction is a systemic process of conservation of a particular... |
| Tipo: Journal article |
Palavras-chave: Evolution; Natural drift; Natural selection; Lineage; Organism; Species. |
| Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2000000200005 |
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| SCHNEIDER,HORACIO. |
| Four DNA datasets were combined in tandem (6700 bp) and Maximum parsimony and Neighbor-Joining analyses were performed. The results suggest three groups emerging almost at the same time: Atelidae, Pitheciidae and Cebidae. The total analysis strongly supports the monophyly of the Cebidae family, grouping Aotus, Cebus and Saimiri with the small callitrichines. In the callitrichines, the data link Cebuela to Callithrix, place Callimico as a sister group of Callithrix/Cebuella, and show Saguinus to be the earliest offshoot of the callitrichines. In the family Pithecidae, Callicebus is the basal genus. Finally, combined molecular data showed congruent branching in the atelid clade, setting up Alouatta as the basal lineage and Brachyteles-Lagothrix as a sister... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: New World monkeys; Platyrrhine; Taxonomy; Molecular; Evolution. |
| Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652000000200005 |
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| Registros recuperados: 176 | |
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