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Teaching is commonly associated with instruction, yet in evolution, immunology, and neuroscience, instructional theories are largely defunct. We propose a co-immunity theory of teaching, where attempts by a teacher to alter student neuronal structure to accommodate cultural ideas and practices is sort of a reverse to…
The main difference between an instructional system and a selectional system is that the instructional system uses information from the environment to change the properties of the object in question, but a selectional system has a large and varied population of objects, and the ones that are most fit for the…
"The project was cancelled," said Nessus. "We found that the Man-Kzin wars put sufficient restriction on kzinti expansion, made you less dangerous. We continued to watch. "Six times over several centuries, you attacked the worlds of men. Six times you were defeated, having lost approximately two-thirds of your male…
But I would like to sound one note of warning. Penicillin is to all intents and purposes non-poisonous so there is no need to worry about giving an overdose and poisoning the patient. There may be a danger, though, in underdosage. It is not difficult to make microbes resistant to penicillin in the laboratory by…
For evolution, which knows nothing, the steps into novelty are blindly taken by mutations, which are random copying “errors” in DNA. Most of these typographical errors are of no consequence, since nothing reads them! They are as inconsequential as the rough drafts you didn’t, or don’t, hand in to the teacher for…
Cancer, we now know, is a disease caused by the uncontrolled growth of a single cell. This growth is unleashed by mutations—changes in DNA that specifically affect genes that incite unlimited cell growth. In a normal cell, powerful genetic circuits regulate cell division and cell death. In a cancer cell, these…
You really don't have to worry about one part of your laptop going rogue and trying out something on its own that the rest of the system doesn't want to do. No, they're all slaves. If they're agents, they're slaves. They are prisoners. They have very clear job descriptions. They get fed every day. They don't have to…
Hamilton's rule is rb - c > 0. Here c is the cost to the giver's fitness (c fewer offspring because of helping), and b is the benefit to the recipient's fitness (offspring gained by the recipient from the help). Here again, "r" is a measure of the relatedness between giver and the receiver [...] Hamilton’s rule says…
The body of an animal operates as a society or ecosystem whose individual members are cells, reproducing by cell division and organized into collaborative assemblies or tissues. In our earlier discussion of the maintenance of tissues (Chapter 22), our interests were similar to those of the ecologist: cell births…
It's important to remember that arguments over evolutionary mechanisms often depend on the deeply held convictions of evolutionary biologists—after all, biologists are people, too! Almost everyone is reluctant to let go of deeply held convictions. Many biologists, in particular, are still attracted to teleological…
Even today a good many distinguished minds seem unable to accept or even to understand that from a source of noise natural selection could quite unaided have drawn all the music of the biosphere. Indeed natural selection operates upon the products of chance and knows no other nourishment; but it operates in a domain…
The process of natural selection has been summed up in the phrase 'survival of the fittest'. This, however, tells only part of the story. 'Survival of the existing' in many cases covers more of the truth. For in hosts of cases the survival of characters rests not on any special usefulness or fitness, but on the fact…
It is natural selection that gives direction to changes, orients chance, and slowly, progressively produces more complex structures, new organs, and new species. Novelties come from previously unseen association of old material. To create is to recombine.
'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…
From thus meditating on the great similarity of the structure of the warm-blooded animals, and at the same time of the great changes they undergo both before and after their nativity; and by considering in how minute a portion of time many of the changes of animals above described have been produced; would it be too…
In these strenuous times, we are likely to become morbid and look constantly on the dark side of life, and spend entirely too much time considering and brooding over what we can't do, rather than what we can do, and instead of growing morose and despondent over opportunities either real or imaginary that are shut from…
It's easy to see that predators (animals that kill and then eat other animals) are working for the downfall of their prey. But it's also true that prey are working for the downfall of their .fedators. They work hard to escape bei and it they all succeeded the predators would starve to death. The same thing holds…
Anybody who teaches human evolution is inevitably asked: Are we still evolving? The examples of lactose tolerance and duplication of the amylase gene show that selection has certainly acted within the last few thousand years. But what about right now? It’s hard to give a good answer. Certainly many types of selection…
Thus, from the war of nature, from famine and death,* the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. 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…
The appointment of death by the agency of carnivora, as the ordinary termination of animal existence, appears therefore in its main results to be a dispensation of benevolence; it deducts much from the aggregate amount of the pain of universal death; it abridges, and almost annihilates, throughout the brute creation…