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Everything is made of atoms. That is the key hypothesis. The most important hypothesis in all of biology, for example, is that everything that animals do, atoms do. In other words, there is nothing that living things do that cannot be understood from the point of view that they are made of atoms acting according to…
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…
When it comes to biology, Catherine Lacey is a Level 40 Hero. That's her ranking on OpenStudy, where the University of Western Australia student spends up to 30 hours per week answering homework questions posed by students around the world. The level indicates time spent on the site, and Hero is the hardest-to-attain…
Our amygdala (pronounced uh-MIG-duh-luh) is about the size and shape of an almond and is part of the limbic area, which resides in the downstairs brain. The amygdala’s job is to quickly process and express emotions, especially anger and fear. This little mass of gray matter is the watchdog of the brain, remaining…
In 1909, the biologist Jakob von Uexküll introduced the concept of the umwelt. He wanted a word to express a simple (but often overlooked) observation: Different animals in the same ecosystem pick up on different environmental signals. In the blind and deaf world of the tick, the important signals are temperature and…
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…
In a typical signaling pathway, proteins are continually being modified and demodified. Kinases and phosphatases work ceaselessly like ants in a nest, adding phosphate groups to proteins and removing them again. It seems a pointless exercise, especially when you consider that each cycle of addition and removal costs…
Every vitamin is made by living cells — either our own, or in other species. Vitamin D is produced in our skin, for example, when sunlight strikes a precursor of cholesterol. A lemon tree makes vitamin C out of glucose. Making a vitamin is often an enormously baroque process. In some species, it takes 22 different…
Others object to the Bald Eagle, as looking too much like a Dindon, or Turkey. For my own part I wish the Bald Eagle had not been chosen the Representative of our Country. He is a Bird of bad moral Character. He does not get his Living honestly. You may have seen him perched on some dead Tree near the River, where…
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…
In 1838, Matthias Schleiden, a botanist, and Theodor Schwann, a physiologist, both working in Germany, had claimed that all living organisms were built out of fundamental building blocks called cells. Borrowing and extending this idea, Virchow set out to create a “cellular theory” of human biology, basing it on two…
Now let us examine more closely what we know scientifically about extinction. At the annual Congress of the American Association for the Advancement of Science, as held approximately ten years ago in Philadelphia, two papers were presented in widely-separated parts of the Congress. One was presented in anthropology…
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…
What's more, most males could not possibly afford to buy a woman's reproductive potential if courtship were a simple economic exchange. What would be an appropriate market price for a nine-month pregnancy, the pain of childbirth, the exhaustion of breast-feeding, and twenty years of maternal care? At least half a…
It’s a common misconception that chimp DNA differs from Homo sapiens sapiens genes by only a single percent, but this number is apocryphal. In actuality, the degree of similarity of human and chimp genetic code depends mostly on how you count. Since all complex organisms from Earth possess great swaths of junk DNA…
The worlds of academia, high fashion, religion, and modern art produce sublime wonders, and sometimes monstrous absurdities. They can afford such creative freedom because their systems of self-regulation and self-perpetuation are insulated from the mun- dane pragmatics of the outside world. Their autonomy endows them…
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 response many organizations adopted then (and continue to pursue AF) is to provide overwhelming amounts of data to the public. This provided a two-fold defense. First, it allowed immediate deniability to any charge of withholding data. Second, the sheer volume of data available meant that almost any argument could…
Human-induced rapid environmental change (HIREC; e.g., climate change or exotic species) has caused global species declines. Although behavioral plasticity has buffered some species against HIREC, maladaptive behavioral scenarios called ‘evolutionary traps’ are increasingly common, threatening the persistence of…
We have altered the environment in a vast number of ways, both small and large. And when animals try to read the cues from our human environment, they can get tricked. They can end up doing something that kills them, loses them the opportunity to reproduce, or simply wastes their time. Scientists call these situations…