In brief, i was very pleased to be in attendance at a well-staged dinner party hosted by the highly talented Jeremy and lovely KateB. One of the conversational topics included the migration of monarch butterflies to their overwintering location, and subsequent population decline as measured by the amount of land they occupy in their Mexico overwintering site (45 acres in 1996, a peak year, to 1.65 acres this year). This number has dropped in the past 10 years in what amounts to a steady decrease, and reasons for the decline have been attributed mainly to sheer loss of habitat due to land conversion to agriculture, herbicide use preventing milkweed growth (milkweed being the main food for Monarch butterflies), and very detrimental weather patterns.
This lead to a complicated conversation regarding the herbicide commonly known as glyphosate, or Monsanto's Round-up. It's an analog of the amino acid glycine, and jams up the synthesis of other amino acids (phenylalanine, tyrosine, and tryptophan) by binding competitively to one of the enzymes which make a precursor to these amino acids. Only plants and micro-organisms have this pathway; mammals get these amino acids from their diets, making glyphosate a highly effective herbicide. On the other end, some bacteria (agrobacterium, in this instance, which is famous because, somewhat ironically, it's commonly used to make transgentic plants anyway), have resistance to glyphosate due to what amounts to a single mutation in that enzyme, and folks have put that gene into various crop plants to get glyphosate-resistant, "Round-up Ready" plants.
There was also discussion of the fact that apparently, there are very few genetically modified (GM) food crops (corn, sugar beets, papaya and soybean crops) grown in the US, including a lack of GM potatoes, wheat, and other vegetables (and please note, numbers are a little elusive regarding wheat). There are 2 different ways you can genetically modify something; either by introducing a gene from a different variety in the same species of that organism (for instance, between varieties of wheat), or introducing a gene from a different species (for instance, inserting a bacterial gene, bacillus thuringiensis, which produces a toxin against caterpillars, into potatoes, corn, etc). A variety of these potatoes were released and grown from 1996-2001, but consumer skepticism lead food processing companies to stop purchasing it, which effectively caused it's removal from the market despite completely safe reports and FDA approval. This is frustrating; " There is broad scientific consensus that genetically engineered crops currently on the market are safe to eat. After 14 years of cultivation and a cumulative total of 2 billion acres planted, no adverse health or environmental effects have resulted from commercialization of genetically engineered crops ", quoted from this excellent article. Furthermore, use of GM plants would decrease the amounts of chemical pesticides and herbicides used (as illustrated with the Bt and glyphosate crops), extend the range of climates in which some crops can be grown (which is pretty important given current climate change data), and nutritionally enhance other crops. Also, given that originally, corn looked like this, humans have been genetically modifying crops via selection for millennia.
Anyway.
An artist named Jason Freely has been making really neat 'cut-away models' of various pop-culture figures (Barbie, My Little Pony, Lego figures, etc) (via this article).
This SMBC comic was sent to me this morning; please disregard the fact that the virus depicted there is one of the alien-looking bacteriophage, which only infect bacteria and do not (directly) cause humans to vomit.
And finally, because i can't resist:
You know why the cowboy purchased a dachshund? He wanted to get a long little doggie.
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