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There are several kinds of speculation about the origins of play: (a) The first holds that play originates as a mutation and therefore an amelioration of dangerous adaptational conJicts. According to John Allman in Evolving Brains, this play mutation constitutes a pre-existing genetic function. (b) Some scholars claim…
When genes are activated, the instructions encoded within their DNA are first transcribed into a related molecule called RNA. Shepherd’s colleague Elissa Pastuzyn showed that the Arc shells can enclose RNA and move it from one neuron to another. And that’s basically what retroviruses do—they use protein shells to…
Darwin’s concept of evolution is centered on natural selection, or survival of the fittest [1]. Although Darwin did realize that organisms possess structures and even entire organs that might not have an extant function, as is the case of rudiments [2], on the whole, selectionist thinking has heavily dominated the…
“You have a mismatched pair of genetic characteristics. Either alone would have been useful, would have aided the survival of your species. But the two together are lethal. It was only a matter of time before they destroyed you." [...] Jdahya made a rustling noise that could have been a sigh, but that did not seem to…
Since no one has succeeded in showing me what I'm missing, we're left with the second option: I'm just incapable of understanding. I'm certainly willing to grant that it may be true, though I'm afraid I'll have to remain suspicious, for what seem good reasons. There are lots of things I don't understand -- say, the…
Amendment No. 1. We will no longer tolerate the tyranny of aging and death. Through genetic alterations, cellular manipulations, synthetic organs, and any necessary means, we will endow ourselves with enduring vitality and remove our expiration date. We will each decide for ourselves how long we shall live. Amendment…
Now it is not that the cell biologists can’t point to experiments which seem to fit their views, as is common in natural science. (After all, the Earth’s Moon does indeed have a geocentric orbit.) Good colleagues of mine like Robert Reis are able to produce nematode worms that live ten times longer than their…
For mankind as a whole, a possession infinitely more valuable than individual life is our genetic heritage, our link with past and future. Shaped through long aeons of evolution, oru genes not only make us what we are, but hold in their minute beings the future – be it one of promise or threat. Yet generic…
The team gathered samples over the course of a year from sewage treatment plants in 71 different cities in 31 states, chosen for their geographic spread and range of obesity rates. The leanest city sampled was Steamboat Springs, Colorado, with an obesity rate of 13.5 percent, while the heaviest was St. Joseph…
Our technology is giving us progressively greater power to keep alive our ancestors' ghosts. First the invention of writing allowed us to preserve their words. Painting and photography allowed us to preserve their faces. The phonograph preserves their voices and the videotape recorder preserves their movement and…
The central problem for any theory of the origin of replication is the fact that a replicative apparatus has to function almost perfectly if it is to function at all. If it does not function perfectly, it will give rise to errors in replicating itself, and the errors will accumulate from generation to generation. The…
The genome of a closely related species will have a high proportion of identical DNA, so it can serve as a blueprint, or “scaffold.” The passenger pigeon’s closest genetic relative is the band-tailed pigeon, which Shapiro is now sequencing. By comparing the fragments of passenger-pigeon DNA with the genomes of similar…
There are many similarities between genes and memes. Just as genes transmitted during sexual intercourse in the biosphere, so are ideas trans¬ mitted during social intercourse in the mental realm, or ideosphere. [...] The memetic realm also hahas some important differences from the genetic realm. Memes combine…
Each of us is ordinary, yet one of a kind. Each of us is standard issue, conceived by the union of two germ cells, nurtured in a womb, and equipped with a developmental program that guides our further maturation and eventual decline. Each of us is also unique, the possessor of a particular selection of gene variants…
Anomaly (2) was observed by Fred Griffith, decades before DNA and the genetic code. He found that if you inject a heat-treated, dead, virulent species of bacteria (pneumococcus S) into a rat previously infected with a nonvirulent species (pneumococcus R), then species R became transformed into species S, thereby…
It is possible that this appearance of non-particulateness is illusory, and that the analogy with genes does not break down. After all, if we look at the inheritance of many genetic characters such as human height or skin-colouring, it does not look like the work of indivisible and unblendable genes. If a black and a…
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…
Human nature as it now exists was formed in accord with the laws of evolution under conditions pertaining well before recorded human history. Fossils discovered in Ethiopia and Kenya now date human ancestors back at least 5 or 6 million years. Distinctly human species arose in Africa at least 2 million years ago…
The active pursuit of uplift really took hold as a scientific field during the great flowering of transhuman culture, an era that also gave us the widespread settlement of space, extensive human genetic modification, nanotech, cognitive science, and the digital emulation of consciousness. It is in fact the convergence…
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…