Cambrian Explosion Most major animal groups appear for the first time in the fossil record some 545 million years ago on the geological time scale in a relatively short period of time known as the Cambrian explosion. Of great worry to Darwin, the explanation of this sudden, apparent explosion persists as a source of numerous major debates in paleobiology. While some scientists believe there was indeed an explosion of diversity (the so-called punctuated equilibrium theory elaborated by Nils Eldredge the late Stephen J. The theory of the Cambrian Explosion holds that, beginning some 545 million years ago, an explosion of diversity led to the appearance over a relatively short period of 5 million to 10 million years of a huge number of complex, multi-celled organisms. appeared in the Cambrian only to rapidly disappear. The Cambrian Explosion is the outcome of changes in environmental factors leading to changes in selective pressures, in turn leading to adaptive diversification on a vast scale. References:
Evolution News & Views: Cambrian Fossils Still a Dilemma for Darwinism 100 Years After Discovery of Burgess Shale Exactly one hundred years ago leading American paleontologist Charles Doolittle Walcott (right) was hiking along Burgess Pass in the Canadian Rockies when he found a slab of shale containing fossil crustaceans. His interest piqued, Wolcott made return trips to the Burgess Shale in the following years where he ultimately collected tens of thousands of fossils. Many of these fossils were extraordinarily well-preserved, and they were mysterious. Darwin himself was aware of this problem in his own day, writing that the lack of fossil evidence for the evolution of Cambrian trilobites "must at present remain inexplicable; and may be truely urged as a valid argument against the views here entertained." The Cambrian seas are now being brought back to life in a new video from Illustra Media titled "Darwin's Dilemma: The Mystery of the Cambrian Fossil Record," set to be released next month.
Evolution: Library: The Cambrian Explosion For most of the nearly 4 billion years that life has existed on Earth, evolution produced little beyond bacteria, plankton, and multi-celled algae. But beginning about 600 million years ago in the Precambrian, the fossil record speaks of more rapid change. First, there was the rise and fall of mysterious creatures of the Ediacaran fauna, named for the fossil site in Australia where they were first discovered. Some of these animals may have belonged to groups that survive today, but others don't seem at all related to animals we know. Then, between about 570 and 530 million years ago, another burst of diversification occurred, with the eventual appearance of the lineages of almost all animals living today. It's important to remember that what we call "the fossil record" is only the available fossil record. It has long been suspected that the sparseness of the pre-Cambrian fossil record reflects these two problems. Internal, genetic factors were also crucial.
Evolution News & Views: BioLogos's Fossil Record Page Conspicuously Missing the Cambrian Explosion The BioLogos website has a static page titled "What does the fossil record show?," which would naturally lead one to expect that if you read the page, then you'll learn what the fossil record shows. What's odd about the page is that the page makes no mention whatsoever of the Cambrian explosion. This is despite the fact that Robert L. Carroll calls the Cambrian explosion "[t]he most conspicuous event in metazoan evolution": The most conspicuous event in metazoan evolution was the dramatic origin of major new structures and body plans documented by the Cambrian explosion. In fact, BioLogos's fossil record page doesn't make any mention of the pattern of explosions of new life-forms common throughout the history of life. Many species remain virtually unchanged for millions of years, then suddenly disappear to be replaced by a quite different, but related, form. So what exactly does the fossil record show? Why the omissions?
James W. Valentine Valentine, J. W. and A. G. Collins (2000). "The significance of moulting in Ecdysozoan evolution." Evolution & Development 2(3): 152-156. Valentine, J. Collins, A. Valentine, J. Roy, K., D. Valentine, J. Valentine, J. Valentine, J. Valentine, J. Roy, K., J. Roy, K., D. Roy, K., D. Valentine, J. Valentine, M. Roy, K., D. Valentine, J. Valentine, J. Valentine, J. Roy, K., D. Valentine, M. Valentine, J. Valentine, J. Valentine, J. Valentine, J. Valentine, J. Valentine, J. Valentine, J. Valentine, M. org | Current Research The goal of my research is to better understand the causal relationships between the genotype and the phenotype, or DNA specifications on the one hand and the morphological “groundpattern” on the other. It has long been presumed that the four-dimensional ontogeny of an organism is encoded in the one-dimensional nucleotide strings, which are commonly referred to as “genes.” But now any quasi-direct genome segment → homology mapping seems unlikely for a number of empirical reasons. To address this complex topic, I am trying to identify formal rules that underpin morphological states, meaning generative functions that entrain DNA specifications.
Life Ascending: The Ten Great Inventions of Evolution (9780393338669): Nick Lane Evolution News & Views: Nick Lane Takes on the Origin of Life and DNA But is Lane's book all that it is touted to be? Lane certainly demonstrates a significant grasp of the relevant fields and conveys his understanding and insights with a masterful eloquence and gripping style. Moreover, Lane's book is of a unique kind. While I certainly do not attempt to disparage Lane's refreshing and brilliantly constructed work, I do seek to offer a critical appraisal of some of the evolutionary explanations he offers. Chapter 1 - The Origin of Life Lane's first chapter provides a refreshing overview of the contemporary models concerned with the origin of the building blocks necessary for the first life, discussing the presented material in the context of Lane's own work related to the origin of life in hydrothermal vents. However, numerous problems abound for the hydrothermal vent hypothesis for the origin of life, as will be discussed in more detail later in this review. For example, the amino acid leucine is specified by six codons. Lane notes, Let's do the math.
Evolution News & Views: Recent Genetic Research Shows Chimps More Distant From Humans, Neanderthals Closer Research published in Nature over the past few months is showing a much greater genetic distance between humans and chimps than previously thought, while revealing a closer one between humans and Neanderthals. A Nature paper from January, 2010 titled, "Chimpanzee and human Y chromosomes are remarkably divergent in structure and gene content," found that Y chromosomes in humans and chimps "differ radically in sequence structure and gene content," showing "extraordinary divergence" where "wholesale renovation is the paramount theme." Of course, the paper attributes these dramatic genetic changes to "rapid evolution during the past 6 million years." One of the scientists behind the study was quoted in a Nature news article stating, "It looks like there's been a dramatic renovation or reinvention of the Y chromosome in the chimpanzee and human lineages." [I]t may help explain the fate of the Neanderthals, who vanished from the fossil record about 30,000 years ago.
Evolution: Richard Dawkins: Quotes from The Selfish Gene and The Blind Watchmaker. Richard Dawkins Discussion of Quotes by Evolutionary Scientist Richard Dawkins Our brains are separate and independent enough from our genes to rebel against them.. we do so in a small way everytime we use contraception. Introduction to Evolution To understand evolution we must know what is evolving (what is matter, what is reality). We have read several books by Richard Dawkins and greatly respect him as an evolutionary scientist. Geoff Haselhurst and Karene Howie Richard Dawkins Quotes: 'The Selfish Gene' Chapter 1 - Why are people? Darwin made it possible for us to give a sensible answer to the curious child whose question heads this chapter. The argument of this book is that we, and all other animals, are machines created by our genes. This brings me to the first point I want to make about what this book is not. I shall argue that the fundamental unit of selection, and therefore of self-interest, is not the species, nor the group, nor even, strictly, the individual.
Evolutionary Biology: Wave Genetics and the Wave Structure of Matter in Space. Genes, DNA, Genetic Modification, Life The Wave Structure of Matter (WSM) and Wave Genetics Introduction: Wave Genetics, Genes, DNA, Genetic Modification, Evolution and Ecology of Life I read an article a few years ago (below) where research from Russia apparently shows that DNA / Genes are Resonant Structures which are subtly interconnected to their Environment by wave interactions. i.e. There does not seem to be much evidence on the internet to support this research on wave genetics, however, there is also very little research on either the Wave Structure of Matter, nor the fact that you can deduce it is the most simple science theory of reality, and then deduce the fundamentals of modern physics (see links on side of page). One important consequence of the Wave Structure of Matter / Wave Genetics applies to Genetic Modification based upon current discrete 'particle' ideas of matter and its interactions. Wave Genetics: On the Wave Structure of DNA and Resonant Interactions of Genes and Environment References Help Humanity