Archive for October, 2009
Genomics offers unprecedented opportunities for testing the central tenets of evolutionary biology formulated by Charles Darwin in The Origin of Species in 1859, later modified into the Central Dogma by the Modern Synthesis during the twentieth century.
In a 2009 review article by entitled “Darwinian evolution in the light of genomics”, published in Nucleic Acid Research, Eugene V Koonin concludes “[m]ajor contributions of horizonal gene transfer… undermine the Tree of Life concept. An adequate depiction of evolution requires the more complex concept of a network or ‘forest’ of life.”
Darwin wrote in The Origin of Species,“[a]lthough the belief that an organ so perfect as the eye could have been formed by natural selection, is enough to stagger any one; yet in the case of any organ, if we know of a long series of gradations in complexity, each good for its possessor, then under changing conditions of life, there is no logical impossibility in the acquirement of any conceivable degree of perfection through natural selection.”
Koonin continues, “[t]here is no consistent tendency of evolution towards increased genomic complexity.” Genomics has failed to demostrate increasing complexity as hypothesized by Darwin.
Evolution needs to synthesis a new mechanism to survive. To this end, Koonin suggests the possibility: “a new synthesis of evolutionary biology might become feasible in a not so remote future.” Until then, genomic evidence fails to support evolution.
Koonin, EV. 2009. Darwinian evolution in the light of genomics. Nucleic Acid Research, 37(4)1011-1034.
The concept of man evolving from some ape or chimpanzee ancestor is central to the evolutionary theory of man. On October 1, 2009, paleontologists announced the discovery of a relatively complete Ardipithecus ramidus fossil skeleton. The fossil is the remains of a small-brained 50 kg (110 lb) female, nicknamed “Ardi”, and includes most of the skull and teeth, as well as the pelvis, hands, and feet. It was discovered in Ethiopia’s harsh Afar desert at a site called Aramis in the Middle Awash region.
From the pelvis and limbs and the presence opposable toes (abductable hallux), researchers have concluded that while Ardi could walk on two feet (bipedal) and climb trees using four limbs (quadrupedal), the walking ability was more primitive than Lucy (Australopithecus afarensis) and could not walk or run for long distances.
Evolutionary paleontologists have estimated that Ardi predated Lucy the iconic early human ancestor which was discovered in 1974 just 74 km (46 mi) away from Ardi’s discovery site.
Not to be forgotten is the dubious history of the Lucy to human link . In 1982, Paleontologist Herbert Wray published an article in Science News, explained: “Lucy’s limb proportions indicate that she had not yet developed an efficient upright gait.”
After conducting a quantitative study of Lucy, paleontologist Charles E. Oxnard concluded in his 1984 book entitled The Order of Man noted that, it “is now being recognized widely that the australopithecines [Australopithecus afarensis] are not structurally… similar to humans.”
In the journal publication Natural History, Stephen Gould, in 1986, took the same stand against the human ancestry of A. afarensis: “In short, he [Oxnard] sees Australopithecines [Lucy] as uniquely different from apes and humans, not as imperfect people on the way up.”
While Ardi is stirring controversy among evolutionists as to exactly where it fits into the evolutionary Tree of Life, it does little to answer the questions: how did apes become human? Given the limited measurements of the fossilized bones without any corresponding molecular or genetic transitional link data, Ardi is very likely to find itself relegated to the same branch as the infamous Lucy—simply a fossilized ape.
Evolution is a theory in crisis. Even students pursuing advanced degrees in science cannot grasp the basics of evolution, according to a new study by University of Guelph researchers.
The finding reveals evolutionary teaching is in chaos from elementary school up, said Ryan Gregory, a professor in Guelph’s Department of Integrative Biology, who conducted the research with former student Cameron Ellis.
The study was published in BioScience and is particularly timely, given that this year is the bicentennial of Charles Darwin’s birth and the 150th anniversary of publication of On the Origin of Species, which underpins understanding of the diversity of Earth’s organisms and their interrelations.
“Misconceptions about natural selection may still exist, even at the most advanced level,” Gregory said.
“We’re looking at a subset of people who have spent at least four years, sometimes even six or seven years, in science and still don’t necessarily have a full working understanding of basic evolutionary principles or scientific terms like ‘theories.’”
Many previous studies have assessed how evolution is understood and accepted by elementary, high school and undergraduate students, as well as by teachers and the general public, Gregory said. But this was the first to focus solely on students seeking graduate science degrees.
The study involved nearly 200 graduate students at a mid-sized Canadian university who were studying biological, physical, agricultural, or animal sciences. When the students were asked to apply basic evolutionary principles, only 20 to 30 per cent could do so correctly, and many did not even try to answer such questions. Of particular interest to Gregory was the finding that many students seem less than clear about the nature of scientific theories.
“This is telling us that traditional instruction methods, while leading to some basic understanding of evolution, are not producing a strong working knowledge that can be easily applied to real biological phenomena.”
The outcome underscores the failure of single cohesive theory of evolution to emerge since the collapse of evolution’s Central Dogma at the turn of the century. Ryan Gregory’s study further demonstrates that education on an non-cohesive theory leads to chaos in the schoolhouse.
Charles Darwin used the term species more than any other term in The Origin of Species— 1,926 times. Defining the term species, however, has been a problem. Darwin wrote, there “is no possible test but individual opinion to determine which of them shall be considered as species”.
Naturalist Henry Alleyne Nicholson explains, “No term is more difficult to define than ‘species,’ and on no point are zoologists more divided than as to what should be understood by this word.”
Geneticist Laura M. Zahn in looking for the genetic distinction between species, published there results in paper entitled “Background Matters” in the October 2009 edition of Evolution and abstracted in Science. Much to their surprise, Zahn and colleagues discovered that no single genetic allele is known to exist that can define the difference between species.
After 150 years, Darwin’s statement continues to be dead on, “It is all-important to remember that naturalists have no golden rule by which to distinguish species.”
Ironically, a book on the origins of an indefinable term, then and now, ascended into a historical phenomenon.