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[The octopus has] an amazing skin, because there are up to 20 million of these chromatophore pigment cells and to control 20 million of anything is going to take a lot of processing power. ... These animals have extraordinarily large, complicated brains to make all this work. ... And what does this mean about the…
The History of Evolution of Organisms consists of two kindred and closely connected parts: Ontogeny, which is the history of the evolution of individual organisms, and Phylogeny, which is the history of the evolution of organic tribes. Ontogency is a brief and rapid recapitulation of Phylogeny, dependent on the…
In consequence of Darwin's reformed Theory of Descent, we are now in a position to establish scientifically the groundwork of a non-miraculous history of the development of the human race... If any person feels the necessity of conceiving the coming into existence of this matter as the work of a supernatural creative…
'Planning' is simply the result of experience read backward and projected into the future. To me the 'purposive' action of a beehive is simply the summation and integration of its units, and Natural Selection has put higher and higher premiums on the most 'purposeful' integration. It is the same way (to me) in the…
Taxonomy (the science of classification) is often undervalued as a glorified form of filing—with each species in its folder, like a stamp in its prescribed place in an album; but taxonomy is a fundamental and dynamic science, dedicated to exploring the causes of relationships and similarities among organisms…
Run the tape again, and let the tiny twig of Homo sapiens expire in Africa. Other hominids may have stood on the threshold of what we know as human possibilities, but many sensible scenarios would never generate our level of mentality. Run the tape again, and this time Neanderthal perishes in Europe and Homo erectus…
If one small and odd lineage of fishes had not evolved fins capable of bearing weight on land (though evolved for different reasons in lakes and seas,) terrestrial vertebrates would never have arisen. If a large extraterrestrial object—the ultimate random bolt from the blue—had not triggered the extinction of…
Asian Homo erectus died without issue and does not enter our immediate ancestry (for we evolved from African populations); Neanderthal people were collateral cousins, perhaps already living in Europe while we emerged in Africa... In other words, we are an improbable and fragile entity, fortunately successful after…
Whatever Nature undertakes, she can only accomplish it in a sequence. She never makes a leap. For example she could not produce a horse if it were not preceded by all the other animals on which she ascends to the horse's structure as if on the rungs of a ladder. Thus every one thing exists for the sake of all things…
We know that nature invariably uses the same materials in its operations. Its ingeniousness is displayed only in the variation of form. Indeed, as if nature had voluntarily confined itself to using only a few basic units, we observe that it generally causes the same elements to reappear, in the same number, in the…
The occurrence of an internal skeleton, in definite relations to the other organ systems, and the articulation of the body into homologous segments, are points in the general organization of Vertebrates to which especial weight must be given. This metameric structure is more or less definitely expressed in most of the…
These germs of disease have taken toll of humanity since the beginning of things--taken toll of our prehuman ancestors since life began here. But by virtue of this natural selection of our kind we have developed resisting power; to no germs do we succumb without a struggle, and to many--those that cause putrefaction…
It will be noticed that the fundamental theorem proved above bears some remarkable resemblances to the second law of thermodynamics. Both are properties of populations, or aggregates, true irrespective of the nature of the units which compose them; both are statistical laws; each requires the constant increase of a…
Genetics has enticed a great many explorers during the past two decades. They have labored with fruit-flies and guinea-pigs, with sweet peas and corn, with thousands of animals and plants in fact, and they have made heredity no longer a mystery but an exact science to be ranked close behind physics and chemistry in…
I believe that life can go on forever. It takes a million years to evolve a new species, ten million for a new genus, one hundred million for a class, a billion for a phylum—and that's usually as far as your imagination goes. In a billion years, it seems, intelligent life might be as different from humans as humans…
The outlook seems grim. Natural selection under civilized conditions may lead mankind to evolve towards a state of genetic overspecialization for living in gadget-ridden environments. It is certainly up to man to decide whether this direction of his evolution is or is not desirable. If it is not, man has, or soon will…
The frequent allegation that the selective processes in the human species are no longer 'natural' is due to persistence of the obsolete nineteenth- century concept of 'natural' selection. The error of this view is made clear when we ask its proponents such questions as, why should the 'surviving fittest' be able to…
In its essence, the theory of natural selection is primarily an attempt to give an account of the probable mechanism of the origin of the adaptations of the organisms to their environment, and only secondarily an attempt to explain evolution at large. Some modem biologists seem to believe that the word 'adaptation'…
The messages that DNA molecules contain are all but eternal when seen against the time scale of individual lifetimes. The lifetimes of DNA messages (give or take a few mutations) are measured in units ranging from millions of years to hundreds of millions of years; or, in other words, ranging from 10,000 individual…
Nature being capricious and taking pleasure in creating and producing a continuous sucession of lives and forms because she knows that they serve to increase her terrestrial substance, is more ready and swift in her creating than time is in destroying, and therefore she has ordained that many animals shall serve as…