![]() ![]() In order to make sense of how the DNA of human beings can be so similar, despite all the important visible and physiological differences among individuals and groups, it is helpful to recount our evolutionary history.Īll mammals, including ourselves, are descended from an ancestral species that lived about one hundred million years ago. This percentage depends only slightly on whether the two people are from the same or from different continents, from the same or from different population groups. If we randomly choose a pair of bases from corresponding sites in two persons, 99.9 percent of the time they will be the same. These forty-six chromosomes contain about six billion base pairs. We have twenty-three pairs of chromosomes, or a total of forty-six, as previously mentioned, in each cell. Chromosomes occur in pairs, one member of each pair from each parent, and the DNA sites in the two corresponding chromosomes match up. In a chromosome, the base pairs are in a precise sequence, and the orderly process of cell division assures the reproduction of this sequence with remarkably few errors. The specific pairing rules – A with T and G with C – are dictated by the three-dimensional structure of the bases. In the double helix, there are four kinds of base pairs: AT, GC, TA, and CG. (I could tell you what these letters stand for, but you wouldn’t understand this essay any better if I did, so I won’t.) There are four of these, commonly designated as A, G, T, and C. The “business” part of the DNA, the part that carries genetic information, is the sequence of nucleotides, or bases, in the molecule. How this is compacted into a microscopic blob some 1/1000 inch long without getting hopelessly tangled is an engineering marvel that is still a puzzle. The DNA in a human chromosome, if stretched out, would be an inch or more in length. There are forty-six such DNA molecules in a human cell, each (along with some proteins) forming a chromosome. Why this curious discrepancy between the evidence of DNA and what we can clearly see? If not DNA, what are the causes of the differences we perceive between individuals and between groups of human beings?ĭNA is a very long molecule, composed of two strands twisted around each other to produce the famous double helix. Most of these average differences are inconspicuous, but some – such as skin color – stand out. Individual differences extend to differences between group averages. Equally clear are individual differences in susceptibility to disease – and in athletic, mathematical, and musical abilities. Still, we only have to look around to see an astonishing variety of individual differences in sizes, shapes, and facial features. The genetic differences between different groups of human beings are similarly minute. ![]() Based on an examination of our DNA, any two human beings are 99.9 percent identical. Venter and Kidd are eminent scientists, so these statements must be reasonable. In the article that followed, the author quoted geneticist Kenneth Kidd: “Race is not biologically definable, we are far too similar.” ![]() So it seems the company did indeed earn its KPIs.In February of 2001, Craig Venter, president of Celera Genomics, commenting on the near-completion of the human genome project, said that “we are all essentially identical twins.” A news headline at the time made a similar point: Are We All One Race? Modern Science Says So. And the Super Bowl Skittles thread, in particular, has earned more than 250,000 views. According to Digiday, Twitter is the best social media marketing tool for advertising during live events. And it's true - for all its silly banter, Skittles' thread wasn't all un-strategic fun and games. The first question the NE Ohio Regional Sewer District Twitter account asked when it joined the fray was why Taco Bell wasn't DMing it back. Skittles was quick to comfort the regional sewer district, saying, "it's ok you have me now." (Taco Bell didn't respond.)īefore the night ended, Skittles kept things meta with its fellow companies by talking with Sour Patch Kids about trying to meet its KPIs (aka key performance indicators, which measure the progress of a goal) before half-time. ![]() For example, Slim Jim entered the chat by proclaiming it was "just here for the meat." In response, Skittles asked, "Meattles collab when?" When Skittles wasn't proposing a nightmarish food team-up, it was bringing some unexpected brand beef to light. ![]()
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