BACKGROUND Lepidosaurs, a group including rhynchocephalians and squamates, are one of the major clades of extant vertebrates. Although there has been extensive phylogenetic work on this clade, its interrelationships are a matter of debate. Morphological and molecular data suggest very different relationships within squamates. Despite this, relatively few studies have assessed the utility of oth...

Kluge, Arnold C;. 1987. Cladistcc Relationships in the Gtjkkonozden (.Squamnta, Sauria). Misc. P I L ~ I ~ . MUS. 2001. liniu. hfzrhzgnn, 173:I-54, fzgs. 1-12.-Thr phylogcrlctic relationships among gekko and pygopod lizards arr investigated. T h e most parsimonious hypothesis contains srvel-a1 well-corroborated tladcs. 1-wcnty-seven synapomorphies rhararterizr the group gckkos + pygopods. Eublr...

Genomic retrotransposons are major genomic components in most eukaryotic organisms. Their abundance in the genome is generally correlated with genome size. These elements spread throughout the genome by a process termed retro-transposition consisting of transcription, reverse transcription and reinsertion of the copied element into a new genomic location. The target sites are relatively unspeci...

This thesis is about phylogenetic trees mathematical graph structures which represent the pattern of evolution. More speci cally, it is concerned primarily with cladograms, the simplest type of phylogenetic tree, and the information they provide about the branching pattern of evolution. Although theoretical in orientation a real dataset is analysed in some detail and a user-friendly program pro...

A cladistic analysis of 87 morphological and life history characters of medusozoan cnidarians, rooted with Anthozoa, results in the phylogenetic hypothesis (Anthozoa (Hydrozoa (Scyphozoa (Staurozoa, Cubozoa)))). Staurozoa is a new class of Cnidaria consisting of Stauromedusae and the fossil group Conulatae. Scyphozoa is redefined as including those medusozoans characterized by strobilation and ...

Most tetrapods possess two nasal organs for detecting chemicals in their environment, which are the sensory detectors of the olfactory and vomeronasal systems. The seventies' view that the olfactory system was only devoted to sense volatiles, whereas the vomeronasal system was exclusively specialized for pheromone detection was challenged by accumulating data showing deep anatomical and functio...