A human leg bone fossil of 300 mya. Material and Method (A) Material found in situ The object (Fig.1-1-1)was discovered in situ by Mr.
Ed Conrad, who had lived in Shenandoah, Pennsylvania, USA for over 30 years. He discovered the subject material over 20 years ago in the suburb of Mahanoy City (Note 2, Fig. 5-1-3), a few kilometers from Shenandoah, where he lived. Ancient teeth raise new questions about origins of modern humans. Eight small teeth found in a cave near Rosh Haain, central Israel, are raising big questions about the earliest existence of humans and where we may have originated, says Binghamton University anthropologist Rolf Quam.
Part of a team of international researchers led by Dr. Israel Hershkovitz of Tel Aviv University, Qaum and his colleagues have been examining the dental discovery and recently published their joint findings in the American Journal of Physical Anthropology. Excavated at Qesem cave, a pre-historic site that was uncovered in 2000, the size and shape of the teeth are very similar to those of modern humans, Homo sapiens, which have been found at other sites is Israel, such as Oafzeh and Skhul -- but they're a lot older than any previously discovered remains. "The Qesem teeth come from a time period between 200,000 -- 400,000 years ago when human remains from the Middle East are very scarce," Quam said.
Evolution News & Views: Asking the Right Questions about the Evolutionary Origin of New Biological Information. For example, a rhodopsin from the Japanese conger eel with Î»max â‰ˆ 480 nm achieved this sensitivity through the interaction of three different amino acid replacements (at sites 195, 195, and 292).
There does not seem to be any way that natural selection could favor an amino acid replacement that would be of adaptive value only if two other replacements were to occur as well.28 In this case, there was no stepwise advantage gained with each successive mutation. Stephen Jay Gould, 1942-2002: Stephen Jay Gould, 1942-2002:In MemoriamBy: David BerlinskiDiscovery InstituteMay 29, 2002 For more information about David Berlinski - his new books, video clips from interviews, and upcoming events - please visit his website at www.davidberlinski.org.
Stephen Jay Gould was the most important paleontologist of his generation, the impact of his life best measured by the wide-spread sense of loss occasioned by his death. Gould wrote widely on a variety of topics in evolutionary theory, and if he sometimes gave the impression of diluting his accomplishments by dividing his attention, the body of work that resulted seemed to have some of the quirkiness and originality of the subjects he chose to study. Evolution News & Views: Ida's Critics Demolish Claims That Fossil Is Human Evolutionary Link. Remember Ida?
The fossil hailed as the "eighth wonder of the world" whose "impact on the world of palaeontology" would be like "an asteroid falling down to Earth"? She was promised to be "the link that connects us directly with the rest of the animal kingdom. " She was touted on a History Channel / BBC documentary, but then there was the bust. Well, Ida's critics have now gotten around to publishing technical articles critiquing the hyped view promoted to the public last year. A recent news release at the University of Texas, "Recently Analyzed Fossil Was Not Human Ancestor As Claimed, Anthropologists Say," explains: 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 6â€‰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. " Evolution News & Views: Fossil Finds Show Cambrian Explosion Getting More Explosive. Cephalopods, which include marine mollusks like squid, octopus, and cuttlefish, are now being reported in the Cambrian explosion fossils.
As a recent BBC news article reports: "We go from very simple pre-Cambrian life-forms to something as complex as a cephalopod in the geological blink of an eye, which illustrates just how quickly evolution can produce complexity," said [evolutionary biologist Martin] Smith. Keep in mind here that "evolution" is a placeholder term for an as-of-yet uncovered mechanism that produces animals like Cephalopods in a "geological blink of an eye. " Darwin's Dilemma is not solved by vague appeals "how quickly" evolution can operate.
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. Very few books are written today which make such a determined and courageous attempt at resolving such fiendish puzzles for modern evolutionary thought.
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. In so doing, I hope to provide insight into where further work needs to be done, and where I think the explanations offered by Lane are inadequate. Life Ascending: The Ten Great Inventions of Evolution (9780393338669): Nick Lane. Signature in the Cell - About the Book. Sternintellbio08.pdf (application/pdf Object) 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 begin with, we currently lack an adequate definition for the term gene.
The layers of codes that reside along a single DNA sequence and that enable hundreds of different RNA and protein products to be encoded, the interleaved organization of loci, and the fact that most genomic expression involves “non-coding” regions — to mention but a few — preclude the classical meaning of the word “gene.” James W. Valentine. Valentine, J.
W. and A. G. Collins (2000). "The significance of moulting in Ecdysozoan evolution. " 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. They included strange forms like Anomalocaris, Opabinia, Wiwaxia, and Hallucigenia. These fossils revealed a mystery: like other Cambrian fauna, these strange soft-bodied fossils appeared in the fossil record abruptly, without evolutionary precursors. 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. " 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. Gould - Models In Paleobiology, 1972), others believe that such rapid acceleration of evolution is not possible; they posit that there was an extended period of evolutionary progression of all the animal groups, the evidence for which is lost in the all but nonexistent precambrian fossil record. Early complex animals in the Paleozoic may have been nearly microscopic. Cambrian explosion. The Cambrian explosion has generated extensive scientific debate.
The seemingly rapid appearance of fossils in the “Primordial Strata” was noted as early as the 1840s, and in 1859 Charles Darwin discussed it as one of the main objections that could be made against his theory of evolution by natural selection. The long-running puzzlement about the appearance of the Cambrian fauna, seemingly abruptly and from nowhere, centers on three key points: whether there really was a mass diversification of complex organisms over a relatively short period of time during the early Cambrian; what might have caused such rapid change; and what it would imply about the origin and evolution of animals.
Interpretation is difficult due to a limited supply of evidence, based mainly on an incomplete fossil record and chemical signatures remaining in Cambrian rocks. 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. 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": Evolution: Richard Dawkins: Quotes from The Selfish Gene and The Blind Watchmaker.
Evolutionary Biology: Wave Genetics and the Wave Structure of Matter in Space. Genes, DNA, Genetic Modification, Life. Evolution News & Views. Evolutionary psychology. Juan Enriquez shares mindboggling new science. Invertebrate Astronauts Make Space History.
Me, Myself and My Stranger: Understanding the Neuroscience of Selfhood. Intelligent Design? - Neil deGrasse Tyson. Hawking: No 'Theory of Everything' Are Humans Turning Into Gods? Simulation of Evolution by Natural Selection.
Viral darwinism. Laurie Santos: A monkey economy as irrational as ours. Human evolution. "Lucy" Kin Pushes Back Evolution of Upright Walking? Becoming Human. Smithsonian Human Origins Program. Te map.
Human Evolution: Oldest Evidence Of Stone Tool Use. Stone Agers Sharpened Skills 55,000 Years Earlier Than Thought. Beneficial Mutations Do Happen. Evolution. Reconstructing the ups and downs of primate brain evolution: implications for adaptive hypotheses and Homo floresiensis.
Evolutionary ethics and morality. Darwinism. Cultural evolution. Evolutionary philosophy. Non-human evolution. Daniel Dennett - Is Evolution an Algorithmic Process? Part 4. Humans' Big Brains Tied To Chimps' Immunity? Evolutionary metaphysics.