Ever wonder what's going on in your body's cells? Incredible numbers of chemical reactions, as generally mentioned in this post on cell biology. And now you can look at many of the documented chemical reactions in one chart.
In this humor-laden short TED talk, philosopher Daniel Dennett discusses things that seem to be intrinsically sweet, sexy, cute or funny. Actually, there is NOTHING that intrinsically has any of these qualities. These qualities don't exist out in the world. Rather, you need to look inside our brains to determine any of these qualities. We are wired to have these reactions when we encounter certain stimuli. There is nothing sweet, for example, in a molecule of glucose.
Please allow me to tell you about today's trip to Missouri's Cuivre River State Park, about 1 1/2 hour drive from St. Louis. My family and our friends had lunch in the picnic area before setting out on a short hike on a half-dry creek bed. To the right you'll see a typical portion of this walk (clicking on these images will give you bigger higher-res versions). No, we didn't see any bears or snakes, but it was a
beautiful day (high temperature about 70, after a summer filled with 100 degree days) and we saw quite a few small spectacular things.How about this blue moth, for example? I looked up this article and it really seems to be a moth and not a butterfly.
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The April, 2010 edition of Discover Magazine profiles biologist Lynne Margulis, famous for her well accepted suggestion that eukaryotic bacteria did not evolve in linear fashion, solely as as a result of natural selection. Rather,
mitochondria and plastids--vital structures within animal and plant cells--evolved from bacteria hundreds of millions of years ago, after bacterial cells started to collect and interactive communities and live symbiotically with one another. The resulting mergers yielded the compound cells known as eukaryotes, which in turn gave rise to all the rest-the protoctists, fungi, plants and animals, including humans.There was a shocking idea at the time (1967), but, as described in this article by Dick Teresi, the more recent ideas of Margulis are even more controversial. The Discover Magazine article documents her arguments that symbiosis is "the central force behind the evolution of new species." This position runs counter to the holding of modern conventional scientific wisdom, that new species arise through "gradual accumulation of random mutations, which are either favored or weeded out by natural selection." Margulis holds that random mutation and natural selection play a minor role and that the big leaps in the evolutionary record "result from mergers between different kinds of organisms, what she calls symbiogenesis." The Discover article takes the form of an interview, in which the dominant theme is that "natural selection eliminates and maybe maintains, but it doesn't create." Margulis argues that the laws of genetics "show stasis, not change." She was prompted by the fact that there is no record of major fossil change until 542 million years ago, yet all of a sudden we see the Cambrian explosion. Stephen Jay Gould coined this phrase, "punctuated equilibrium," "to describe a discontinuity in the appearance of new species." According to Margulis, her explanation of symbiogenesis explains these discontinuities and should thus be considered the primary mechanism for evolution. Margulis carefully distinguishes her approach from arguments based on "intelligent design." She holds that those who advocate for "intelligent design" have nothing meaningful to offer to the scientific conversation. [More . . . ]
