The genealogy and nomenclature of predatory dinosaurs and birds

lovethee History

The study of how predatory dinosaurs were related to one another, their phylogenetics, is an area of much action these days. (Walking dinosaur costume) This is different from most of this century, a period in which theropods were thought to form two separate and rather simple dead-end groups that left no living descendants. It is now clear that theropod evolution was much more complex, and includes the origin of birds. (Animatronic dinosaur)Once a plausible phylogenetic anangement is worked out, then the groups need to be named. Naming such gToups and species is taxonomy; formally amanging them in ordered groups is systematics. All this may sound dry and dull, but I’ve never found it so. After all, many people love trivia games and crossword pvzzles, and figuring out how to identi$r, arrange, and name once-living things is much more challenging. I tend to be like the hobbit who wants everything “set out fair and square, with no contradictions.” This is a futile desire. The sands of phylogeny and taxonomy are always shifting beneath the dinosaurologist’s feet, and always will.


There are two basic ways to e>plore phylogenetic relationships. realistic animatronic dinosaur One is based on molecular studies of the genetic material contained in soft tissues. There are various ways to conduct these studies; one of the more recent methods-considered by many the best available way of determining animal relationship-is a process called DNA-DNA hybridization.’ Birds and their crocodilian relatives can be studied molecularly, but of course since we have no soft tissues of dinosaurs, they cannot be. This is an important drawback, as I shall explain below. On the other hand, there are those that do not have much confidence in molecular phylogenetics; it is a deeply complex issue that will take time to resolve.