In the Light of Evolution Volume I: Adaptation and Complex Design (2007) / Chapter Skim
Currently Skimming:
Pages 3-22
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 3... ...
With Darwin's discovery of natural selection, the origin and adaptations of organisms were brought into the realm of science. The adaptive features of organisms could now be explained, like the phenomena of the inanimate world, as the result of natu ral processes, without recourse to an Intelligent Designer.
|
From page 4... ...
/ Francisco J Ayala necessity, randomness and determinism, jointly enmeshed in the stuff of life.
|
From page 5... ...
Authors, such as William Paley, argued that the complex design of organisms could not have come about by chance or by the mechanical laws of physics, chemistry, and astronomy but was rather accomplished by an intelligent Designer, just as the complexity of a watch, designed to tell time, was accomplished by an intelligent watchmaker. it was Darwin's genius to resolve this conceptual schizophrenia.
|
From page 6... ...
Darwin brings about the evidence for evolution because evolution is a necessary consequence of his theory of design. INTELLIGENT DESIGN: THE ORIGINAL VERSION William Paley (1743–1805)
|
From page 7... ...
Darwin's Greatest Discovery / that only an omnipotent God could account for the perfection, multitude, and diversity of the designs. There are chapters dedicated to the complex design of the human eye; to the human frame, which displays a precise mechanical arrangement of bones, cartilage, and joints; to the circulation of the blood and the disposi tion of blood vessels; to the comparative anatomy of humans and animals; to the digestive tract, kidneys, urethras, and bladder; to the wings of birds and the fins of fish; and much more.
|
From page 8... ...
/ Francisco J Ayala tion ‘‘by imitating, in glasses made from different materials, the effects of the different humors through which the rays of light pass before they reach the bottom of the eye.
|
From page 9... ...
he discusses the fish's air bladder, the viper's fang, the heron's claw, the camel's stomach, the woodpecker's tongue, the elephant's proboscis, the bat's wing hook, the spider's web, insects' compound eyes and metamorphosis, the glowworm, univalve and bivalve mollusks, seed dispersal, and on and on, with accuracy and as much detail as known to the best biologists of his time. The organized complexity and purposeful function reveal, in each case, an intelligent designer, and the diversity, richness, and pervasiveness of the designs show that only the omnipotent Creator could be this intelligent Designer.
|
From page 10... ...
science, thereby, made a quantum leap. DARWIN'S ‘‘MY THEORY'' Darwin considered natural selection, rather than his demonstration of evolution, his most important discovery and designated it as ‘‘my theory,'' a designation he never used when referring to the evolution of organisms.
|
From page 11... ...
in his letters, Darwin would offer sympathy and encouragement to the occasionally dispirited Wallace for his ‘‘laborious undertaking.'' in 1858, Wallace came upon the idea of natural selection as the explanation for evolutionary change and he wanted to know Darwin's opinion about this hypothesis, because Wallace, as well as many others, knew that Darwin had been working on the subject for years, had shared his ideas with other scientists, and was considered by them as the eminent expert on issues concerning biological evolution. Darwin was uncertain how to proceed about Wallace's letter.
|
From page 12... ...
. in 1858, Darwin was at work on a multivolume treatise, intended to be titled ‘‘on natural selection.'' Wallace's paper stimulated Darwin to write The Origin, which would be published the following year.
|
From page 13... ...
The design of organisms as they exist in nature, however, is not ‘‘intelligent design,'' imposed by God as a supreme engineer or by humans; rather, it is the result of a natural process of selection, promoting the adaptation of organisms to their environments. This is how natural selection works: individuals that have beneficial variations, that is, variations that improve their probability of survival and reproduction, leave more descendants than individuals of the same species that have less beneficial variations.
|
From page 14... ...
There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved (Darwin, 1859b, pp. 489–490; emphasis added)
|
From page 15... ...
These individuals reproduced and, thus, the mutations providing resistance increased in frequency over the generations, so that eventually the population was no longer susceptible to the pesticide. The adaptation had come about by the combined processes of mutation and natural selection.
|
From page 16... ...
natural selection is much more than a ‘‘purifying'' process, for it is able to generate novelty by increasing the probability of otherwise extremely improbable genetic combinations. natural selection in combination with mutation becomes, in this respect, a creative process.
|
From page 17... ...
Accordingly, natural selection favored genes and gene combinations that increased the functional efficiency of the eye. such mutations gradually accumulated, eventually leading to the highly complex and efficient vertebrate eye.
|
From page 18... ...
But there are important features that distinguish the kind of ‘‘design'' achieved by natural selection, namely the adaptations of organisms, from the kind of design produced by an intelligent designer, an engineer. An engineer has a preconception of what the design is supposed to achieve and will select suitable materials and arrange them in a preconceived manner so that it fulfills the intended function.
|
From page 19... ...
. natural selection is an opportunistic process.
|
From page 20... ...
natural selection accounts for the ‘‘design'' of organisms because adaptive variations tend to increase the probability of survival and reproduction of their carriers at the expense of maladaptive, or less adaptive, variations. The arguments of intelligent design proponents that state the incredible improbability of chance events, such as mutation, to account for the adaptations of organisms are irrelevant because evolution is not governed by random mutations.
|
From page 21... ...
some are beneficial, most are not, and only the beneficial ones become incorporated in the organisms through natural selection. The adaptive randomness of the mutation process (as well as the vagaries of other processes that come to play in the great theater of life)
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.