Sökning: "ancestral sequences"
Visar resultat 1 - 5 av 28 avhandlingar innehållade orden ancestral sequences.
1. Computational problems in evolution : Multiple alignment, genome rearrangements, and tree reconstruction
Sammanfattning : Reconstructing the evolutionary history of a set of species is a fundamental problem in biology. This thesis concerns computational problems that arise in different settings and stages of phylogenetic tree reconstruction, but also in other contexts. LÄS MER
2. The Dawn of a New Age : Interrelationships of Acoela and Nemertodermatida and the Early Evolution of Bilateria
Sammanfattning : Deciphering the rapid emergence of bilaterian animals around the time of the Cambrian Explosion and reconstructing the interrelationships of animal groups have long been two of the most elusive problems in Zoology. This thesis concerns the phylogenetic interrelationships within and among Acoela and Nemertodermatida, two groups of small worms that are believed to be basal bilaterians and which may provide important clues for understanding the early evolution of animals. LÄS MER
Sammanfattning : Identifying the processes involved in the evolution of suppressed recombination between sex chromosomes and understanding their consequences for the evolutionary dynamics of sex-linked loci have been major topics of research during the last century. In this thesis, I used the avian ZW system, where females are the heterogametic sex, to investigate the underlying processes in sex chromosome evolution in birds. LÄS MER
4. An evolutionary view of the taxonomy and ecology of Inocybe (Agaricales) with new perspectives gleaned from GenBank metadata
Sammanfattning : Inocybe (Inocybaceae) is one of the most speciose genera among the gilled mushrooms (Agaricales) but large parts of its taxonomy and evolutionary history remain poorly explored. The present thesis sho... LÄS MER
Sammanfattning : Autolytines constitute a well delineated group of syllid polychaetes, separated from other syllids by the presence of a sinuous pharynx, lack of ventral cirri and reproduction with dimorphic sexes. The group comprises c. 170 nominal species distributed worldwide, mostly inhabiting hard substrates restricted to the continental shelf. LÄS MER