Phylogeny Problem Research Articles

A standardized G‐banded karyotype for the raccoon (Procyon lotor)compared with the domestic cat

Abstract We propose a standardized karyotype for the raccoon (Procyon lotor; 2n = 38, FN 74) and compare it with that of the domestic cat (2n = 38, FN 72). Numerous chromosomes (12) have similar and sometimes identical G‐banding and 14 chromosome pairs have remained intact. Other chromosomes apparently differ by Robertsonian translocations and inversions. The conservation of these karyotypes is remarkable considering that the divergence of procyonids and felids predates 50 million years B.P. However, the common diploid number of 38 is not a primitive retention, as sometimes hypothesized. Instead, cats and raccoons converged on this chromosome number by a different series of translocations. The unsolved problems of carnivore phylogeny could benefit from a combination of high resolution banding and molecular cytogenetic analyses.

Triangulating 3-Colored Graphs

The problem of determining whether a vertex-colored graph can be triangulated without introducing edges between vertices of the same color is what is of interest here. This problem is known to be polynomially equivalent to a fundamental problem in numerical taxonomy called the perfect phylogeny problem, which is concerned with the inference of evolutionary history. This problem is also related to the problem of recognizing partial k-trees, a class of graphs that has received much attention recently. The problem in its general form is NP-complete and can be solved in $O( n^{k + 1} )$ time, where n is the number of vertices and k the number of colors. In this paper, a linear time algorithm for the case of 3-colored graphs is presented.

Man and molecular phylogenies

Abstract The problem of the phylogenetic relationships of the extant members of Hominoidea is a long‐standing one in evolution and anthropology. Morphological, fossil, and other more traditional data led to a variety of proposed trees with no clear consensus. It was hoped that molecular data, which should be an independent source of information, would shed light on the problem. Until recently these hopes have not been realized. However, two sources of molecular data have recently been obtained which appear to solve the problem with reasonable assurance. These data involve total measurement of DNA divergence among taxa using DNA‐DNA hybridization and more detailed sequence data of a globin pseudogene. The theory behind the use of each kind of data for solving the Hominoidea problem is discussed as well as the problem of species phylogenies and gene phylogenies. The main phylogenetic conclusion is that man and chimpanzees are the most closely related extant primates, followed by gorillas, orangutans, and gi...

Efficient algorithms for inferring evolutionary trees

AbstractIn this paper, we examine two related problems of inferring the evolutionary history of n objects, either from present characters of the objects or from several partial estimates of their evolutionary history. The first problem is called the Phylogeny problem, and second is the Tree Compatibility problem. Both of these problems are central in algorithmic approaches to the study of evolution and in other problems of historical reconstruction. In this paper, we show that both of these problems can be solved by graph theoretic methods in linear time, which is time optimal, and which is a significant improvement over existing methods.

Invertebrate relationships: patterns in animal evolution

Phylogenetic study is an important corner-stone of biology, for the evolutionary relationships between groups of animals bear heavily on the analysis of their physiology, behaviour and ecology. Despite this, there have been few books which analyse the diversity of animal life in terms of its origins, and the relationships between different groups. In this book Pat Willmer draws on her experience of teaching invertebrate zoology to produce a stimulating account of both the relationships between invertebrate phyla and of the phylogenetic pattern of the animal kingdom. After reviewing the current state of the subject, the author discusses the various sources of evidence - structural, chemical, genetic, embryological and fossil - which bear upon the question of how living animals are related to each other. Much of this evidence has accumulated over the last two decades, yet there has been surprisingly little appreciation of the implications it has on phylogenetic research. Dr Willmer goes on to apply these lines of evidence to particular groups of invertebrates, discussing many of the classical problems of invertebrate phylogeny - the origins and relations of the lower metazoa, arthropod phylogeny, the protostome/deuterostome question, and the origin of chordates from invertebrates. The prevalence of convergent evolution is a strong theme of the book, as it becomes clear that many features, from details of cell chemistry and structure to overall body plan and life history, have been invented repeatedly and independently under similar selection pressures. This book succeeds in bringing together the previously scattered literature on invertebrate phylogeny, forming a unique introduction to this fascinating and controversial subject, and up-to-date review of invertebrate zoology.

The Selection of behavior: the operant behaviorism of B.F. Skinner: comments and consequences

Preface List of contributors Introduction: the operant behaviorism of B. F. Skinner A. Charles Catania Part I. Canonical Papers of B. F. Skinner: 1. Selection by consequences 2. Methods and theories in the experimental analysis of behavior 3. The operational analysis of pyschological terms 4. An operant analysis of problem solving 5. Behaviorism at fifty 6. The phylogeny and ontogeny of behavior Part II. Summing Up: 7. What are the scope and limits of radical behaviorist theory Stevan Harnad 8. Problems of selection and phylogeny, terms and methods of behaviorism A. Charles Catania Appendix. Biographical sketch and bibliography of works by B. F. Skinner Acknowledgments and notes References Name index Subject index.

Edmund Beecher Wilson, Class of '81

Edmund Beecher Wilson was born in Geneva, Illinois in 1856. He attended Antioch College, the University of Chicago, Yale, and Johns Hopkins (Ph.D. 1881). Most of his professional life was spent in the Zoology Department of Columbia University together with his close friend, Thomas Hunt Morgan. They were dominant figures in developing the Chromosome Theory of Heredity. Wilson began his professional life as a conventional 19th century biologist studying problems of systematics, morphology, and phylogeny. Soon he became a key figure in the newer experimental disciplines of embryology, cytology, and heredity. He is remembered today largely for his superb synthesis of these three fields in The Cell in Development and Heredity. He died in 1939.

Phylogeny and classification of the normapolles

The principal advances in the study of Normapolles pollen grains are summarised. Problems of phylogeny and classification of the group are reviewed and its biostratigraphic importance is emphasised.

A new species of Niptomomys (Microsyopidae) from the early eocene of Wyoming.

A new, relatively large species of Niptomomys is described from the late Wasatchian of the Bighorn Basin of Wyoming. The importance of a stratigraphic approach to problems of species-level phylogeny is stressed, and then applied to an investigation of the evolutionary history of Niptomomys. The new Niptomomys species may have evolved gradually from early Wasatchian Niptomomys doreenae in the Bighorn Basin and vicinity, or it may have evolved elsewhere and replaced the earlier form relatively rapidly. The available evidence is not yet sufficient to distinguish between these two alternatives.

Morphology and twentieth-century biology: a response.

I am gratified to find that ideas I published a few years ago in Life Science in the Twentieth Century have stimulated a controversy about some important issues in the history of biology. In the Introduction to that book I wrote, "If this book has any lasting merit . .. it will be less in the questions that it answers than in those it raises . . . The best history tries to phrase issues so . . . that others can go beyond and investigate them more thoroughly." This is exactly what Jane Maienschein, Ronald Rainger, and Keith Benson have done. I am glad they took me at my word and challenged ideas that, more than five years ago, I advanced as one way of organizing our thinking about the development of biology between roughly 1880 and 1930. The foregoing papers offer several valid criticisms of the basic thesis, I outlined in Life Science in the Twentieth Century (1975; 1978), Thomas Hunt Morgan: The Man and His Science (1978), and "Naturalists and Experimentalists: The Genotype and the Phenotype" (1979).' Simply stated, my argument is that American biology between about 1880 and 1930 witnessed a sharp, radical shift in methodology and the problems addressed. That shift proceeded from an interest in problems of phylogeny and natural history, pursued largely with descriptive methods, to an interest in problems of embryogenesis, heredity, and physico-chemical processes, pursued with analytical and experimental methods. The shift occurred because younger workers in the 1880s and 1 890s became tired of pursuing problems of phylogeny and of the endless speculations that seemed at the time to attend much of the work of nineteenth-century morphologists, including their own teachers. In a sense, younger biologists "revolted" against the problems pursued by and the methods espoused by older investigators. In breaking with the older tradition (often exemplified for younger workers by morphology),

A previously unreported throat muscle in Scolecophidia (Reptilia: Serpentes), with comments on other scolecophidian throat muscles

Summary A throat muscle, present in Scolecophidia but absent in other snakes, is reported here for the first time. This muscle passes from the genial region of the lower jaw to the mucosa of the floor of the oral cavity. The precise homology of the muscle is uncertain. In Typhlops at least, it appears to receive hypoglossal innervation, and can thus be assigned to the hypobranchial-spinal muscle group. It may have been derived from a lateral portion of the genioglossus that inserts on the floor of the oral cavity, as is found in diverse lizards, or it may have been derived from the snake geniotrachealis. Present evidence tends to favour the former hypothesis. While the evolutionary origin of the scolecophidian muscle remains unclear a new name is required, it is here termed the geniomucosalis, after the regions of origin and insertion. Some major problems of scolecophidian phylogeny are discussed as a background to remarks on the possible cladistic implications of the presence of the geniomucosalis in Scolecophidia. The conclusion is reached that although the muscle further contributes to the considerable phenetic gap between Scolecophidia and other snakes, while its homology remains uncertain the geniomucosalis is of limited significance in a cladistic analysis. Numerous points of difference are noted between my observations on various scolecophidian throat muscles, and observations reported in the literature.

NADP-dependent aromatic alcohol dehydrogenase in polyploid wheats and their diploid relatives. On the origin and phylogeny of polyploid wheats

The three major isoenzymes of the NADP-dependent aromatic alcohol dehydrogenase (ADH-B), distinguished in polyploid wheats by means of polyacrylamide gel electrophoresis, are shown to be coded by homoeoalleles of the locus Adh-2 on short arms of chromosomes of the fifth homoeologous group. Essentially codominant expression of the Adh-2 homoeolleles of composite genomes was observed in young seedlings of hexaploid wheats (T. aestivum s.l.) and tetraploid wheats of the emmer group (T. turgidum s.l.), whereas only the isoenzyme characteristic of the A genome is present in the seedlings of the timopheevii-group tetraploids (T. timopheevii s.str. and T. araraticum).The slowest-moving B(3) isoenzyme of polyploid wheats, coded by the homoeoallele of the B genome, is characteristic of the diploid species Aegilops speltoides S.l., including both its awned and awnless forms, but was not encountered in Ae. bicornis, Ae. sharonensis and Ae. longissima. The last two diploids, as well as Ae. tauschii, Ae. caudata, Triticum monococcum s.str., T. boeoticum s.l. (incl. T. thaoudar) and T. urartu all shared a common isoenzyme coinciding electrophoretically with the band B(2) controlled by the A and D genome homoeoalleles in polyploid wheats. Ae. bicomis is characterized by the slowest isoenzyme, B(4), not found in wheats and in the other diploid Aegilops species studied.Two electrophoretic variants of ADH-B, B(1) and B(2), considered to be alloenzymes of the A genome homoeoallele, were observed in T. dicoccoides, T. dicoccon, T. turgidum. s.str. and T. spelta, whereas B(2) was characteristic of T. timopheevii s.l. and only B(1) was found in the remaining taxa of polyploid wheats. The isoenzyme B(1), not encountered among diploid species, is considered to be a mutational derivative which arose on the tetraploid level from its more ancestral form B(2) characteristic of diploid wheats.The implication of the ADH-B isoenzyme data to the problems of wheat phylogeny and gene evolution is discussed.

Some problems of the phylogeny and systematics of Lacertilia

Some problems of the phylogeny and systematics of Lacertilia

Architecture of Trees in the Rain Forest of Morobe District, New Guinea

The architectural spectrum of the rain-forest appears to be qualitatively the same in New Guinea as previously reported in tropical Africa or America. However, the study of Asiatic and Melanesian trees leads to a broader understanding of the architectural range in pantropical families of flowering plants, and suggests an approach to the understanding of many problems in taxonomy, phylogeny, biogeography, and forest ecology. THE ARCHITECTURE OF TREES in the tropics, a new subject for botanical research, has already been applied to taxonomy, as, for example, in the Euphorbiaceae (Halle 1971). In the present paper, I wish to introduce another aspect of tree architecture, which is biogeographical rather than taxonomical. The introduction of the topic of tree architecture by Halle and Oldeman (1970) was mainly founded upon African and American records, and was comparatively poor in original data about Asiatic trees. Taking into account the particular richness of the Asiatic flora, and its well-known importance for tropical botany, filling such a gap was a preliminary essential for the satisfactory formulation of the problem of architectural evolution in trees. A visit to Australian New Guinea in 1972 provided an opportunity to make a first study of the architecture of Asiatic and Melanesian trees, the main results of which are summarized below.' All the architectural models previously discovered in Africa and America were found easily in the lowland rain forest around Lae, and in the submontane rain forest around Bulolo, Morobe District. A significant, if negative, result is that-contrary to a priori views-no new architectural models were found during my visit to Asia. Thus, as far as I know, the architectural spectrum of the rain forest appears to be qualitatively the same in all parts of the tropics. Of course, the possibility of quantitative variation within the spectrum cannot be denied, some models being favored in some countries either for historical reasons or by environmental conditions, but this supposition is speculative, as a study which would reveal this still remains to be done. Even if the total number of known models has not been augmented, this study of Asian trees leads to a better understanding of the architectural range in several pantropical families of flowering plants. From the 76 New Guinea species from 45 families whose form was studied, I extract 11 which were observed in particularly good circumstances. Schuurmansia henizgsii K. Schum. OCHNACEAE Cf. NGF 40163 from Red Hill, near Lae, Morobe District. Leeuwenberg's Model. This very common small tree, usually less than 10 meters high, is one of the finest plants around Lae at flowering time. Figure 1 a and b represents a well-grown flowering specimen. All the serial axes are orthotropic and equivalent to one another, the only variation being a quantitative one such that, when the branching increases, the size of the successive axes, and the length of their leaves, progressively decreases, as advanced by Corner (1949) in his Durian Theory. Apical inflorescences appear simultaneously on all the upper axes, the lower ones remaining sterile from then on. Owing to these architectural features, Schuurmansia heningsii belongs to Leeuwenberg's model, as defined by Halle and Oldeman (1970). Apart from the characteristics of the model itself, Schuurmansia heningsii offers some individual morphogenetic features, such as the stilt-roots supporting the seedling axis, and the periodic growth which is indicated by the series of bud-scale scars at each level of temporarily interrupted growth. This is the first record of Leeuwenberg's model in Ochnaceae. However, in the same family, the African Lophi'ra alata Banks possesses an architecture related to the present one, although its aerial axes, after the first growth, are no longer equivalent to one another, since some of them grow upright to form a sympodial trunk (Kwan Koriba's model). 1 I wish to express my gratitude to John S. Womersley, head of the Division of Botany at Lae, to the members of his staff, particularly Mark J. E. Coode, for their help in my field-work, and to Anna Cook and Bokinane, for their assistance. BIOTROPICA 6(1): 43-5

Current Problems of Lower Vertebrate Phylogeny. Proceedings of the Fourth Nobel Symposium Held in June 1967 at the Swedish Museum of Natural History (Naturhistoriska riksmuseet) in Stockholm.Tor Orvig

<i>Current Problems of Lower Vertebrate Phylogeny. Proceedings of the Fourth Nobel Symposium Held in June 1967 at the Swedish Museum of Natural History (Naturhistoriska riksmuseet) in Stockholm.</i>Tor Orvig

Cytological Observations on some Northwest Himalayan Orchids

SUMMARYA cytotaxonomic study in the Himalayan orchids was undertaken to delineate the evolutionary trends and to unravel problems of phylogeny and taxonomy. Cytological observations on 20 species from northwest Himalayan region are reported. On the basis of secondary association among bivalents and chromosome numbers in multiples, it has been suggested that all the species of Habenaria investigated by us were hexaploid. The formation of bivalent chains and occurrence of dicentric bridges and fragments in Neottia listeroides were attributed respectively to translocations and inversions at meiosis. In Epipactis belleporine, in addition to four pollen grains in a tetrad, one to two « sporads» were noted. A high proportion of taxa investigated were found to be polyploid. A number of genera had species with aneuploid numbers.

An Aspect of Morphogenesis in the Ciliate Protozoa*

SYNOPSIS. Stomatogenesis or new mouth formation sensu lato repnts an explicit example of a major morphogenetic phenomenon le life cycle of most ciliate Protozoa. Investigations of the process a number of approaches may yield data of considerable value. The present paper 3 such approaches are treated in some detail.udies of stomatogenesis can be of importance in providing addial information of significance on the structure and physiology a given organism. Five major types or categories of stomatoesis in ciliates are recognized. These are defined and discussed. search related to such an intrinsic value of the phenomenon the K carried out is generally only descriptive, and the most importechnic employed is some method of silver impregnation.a comparative approach is used, then attention may be focused possible homolegies in stomatogenesis as it occurs in diverse ies of ciliates. Such data are (or potentially are) of value not in the practical taxonomy of the organisms involved but also onsideration of phylogenetic and evolutionary interrelationships ing the higher groups comprising the entire subphylum Ciliophora. Such application of comparative studies may well become a very fruitful approach to certain problems in ciliate phylogeny; 2 examples are discussed briefly. Silver impregnation technics are again indispensable.Perhaps stomatogenesis will prove most valuable in the hands of developmental biologists who are seeking to solve 2 of the most intriguing problems in cell biology today: the exact origin of new kinetosomes (or centrioles), and their precise morphogenetic role in the life cycle of a cell or unicellular organism. Since this third approach to the study of stomatogenesis is of necessity a dynamic one, the researcher must employ sophisticated experimental technics to obtain data at the molecular and macromolecular levels of both organization and function. Some progress in this area has already been made, but the availability of “ideal” organisms has perhaps not been as widely realized as it should. Certain of the “higher” ciliates have a mode of stomatogenesis which would lend itself beautifully to fruitful investigation of problems concerning both replication or neoformation of kinetosomes and their possible role in fibrillogenesis in unicellular organisms.

Chemical characters in plant taxonomy: some possibilities and limitations.

Abstract

A Reevaluation of the Early History of the Frogs. Part I

SOME of the results of a symposium, Problems in salientian phylogeny, were published in this journal in 1957. Of the three papers published, two (Brattstrom, 1957; Jameson, 1957) were essentially reviews of the literature. One article by Orton (1957) reviewed her interesting ideas on the utilization of tadpole morphology in the problem of frog phylogeny. From the viewpoint of paleontology, the most important paper in the symposium is that by Brattstrom which summarizes all the classic phylogenetic concepts found in most accepted texts (Romer, 1945; Colbert, 1955; Piveteau, 1955). In consideration of our admitted lack of knowledge (Brattstrom, 1957; Laurent, 1948) on such basic facts as the anatomy of living frogs and the incomplete fossil record, the phylogenetic tree presented by Brattstrom is misleading because it hides the gaps in our knowledge. 'rhe purpose of this paper is to point out recent discoveries in salientian paleontology and to evaluate the contributions of these discoveries to the problems of classification, phylogeny, and zoogeography in this group.

The descent of man and the present fossil record.

It is a most pleasant duty, first of all, to express my appreciation for the honor of being invited to talk about some problems in human phylogeny at this year's Symposium at Cold Spring Harbor. I hesitated before suggesting such a topic. There are so many American experts in paleanthropology, that I seriously doubt my ability to fulfill your expectations. I am quite certain that many of my colleagues here would be able to fill the assignment better than I can. If I, nevertheless, dare to discuss this subject here, it is only because the picture offered by the fossil documentation of human phylogeny is not a static one; it is constantly changing, with an ever increasing velocity. Therefore the attempt to present the available factual basis and the hypotheses which can be discussed at this time might be of some value.