maize is so fucking weird. like i can’t even cover it in one post so i’m just gonna focus on one of the LARGEST reasons it’s so fucked up in this post so buckle in babes it’s time for a wild ride
to understand maize genetics on a fundamental level, we have to understand the work of Dr. Barbara McClintock, a brilliant botanist who dedicated her life to how fucked up corn is while simultaneously never being taken seriously because she was a woman. McClintock noticed a few things while studying maize in the early 1940s. as you might know, maize doesn’t always look all yellow; sometimes the kernels are colored differently, like this:
well yeah about that, she started noticing correlations in how the kernels were colored based on certain cases of the genes (imagine them as sections of DNA) she was looking at being rendered nonfunctional (or being “broken”).
for instance, lets say we breed a maize plant thats supposed to have only purple cobs, but when it grows up, the cobs are a different color entirely, or patterned differently, or completely different from what we were expecting. this happened a lot to McClintock. like, constantly. after testing the DNA of the plant, she would find that the reason the plant didn’t bear purple cobs was because of other genes randomly teleporting into the middle of the gene she was testing for. so our purple maize plant wouldn’t make purple cobs because some random ass shit inserted itself in the actual fucking middle of the ‘make purple pigment’ gene, causing it to ‘break’. we now know these teleporting little shits as “transposons”, and they’re a normal thing that casually happens IN ALL LIVING THINGS. but they didn’t know that in the 1940s.
so not only did McClintock have random shit jumping into other random shit, but she had a REALLY hard time on her primary project of mapping the maize genome (the act of building a basic outline of which gene goes where on each chromosome) because it seemed like no matter what gene she was looking at, it would be in a different place in the genomes of all her plants (it should be noted that as we know them to be, many genes really are stable and stay in their same positions consistently through a species. for instance, lets say that there’s a gene on your 5th chromosome that codes for eye color. although your eye color may be different than the person next to you, their eye color gene is still located on the 5th chromosome; the code is just different. in McClintock’s case, NOTHING was staying consistently ANYWHERE between multiple samples of corn).
this was a BIG mistake. she continued to publish her results for the next 15 years until she got so much hate she had to stop publishing the evidence she found not only for the existence of transposons, but her theories as to why they were there and what purpose they serve. other scientists in her (primarily male) field of experimental genetics REFUSED to believe this from her until nearly two decades later, when two male scientists- fellow biology students may recognize the names Francois Jacob and Jacques Monod, who worked with confirming the regulation of the lac operon and are still considered the fathers of epigenetics despite you know, not actually being the fathers of epigenetics since she did it twenty years earlier and i personally refuse to worship their shitty ass milk triumph- confirmed that genes could be, you know, regulated, and that the genome could be changed over the course of your life and that transposons were VERY MUCH possible and were also rediscovered in the following decade in similar encounters. anyway she casually won the nobel prize for her work in 1983, literally 40 years after she discovered it when everyone realized that she had been right all along and that they’d been belittling her and shitting on her for decades over it lol.
anyway, all that aside: why is corn weird? why did it take until literally 2009 for us to map the maize genome for the first time?
70-85% of the genome of maize, in it’s natural form, literally does not stay in one place between generations. it just doesn’t. it fumbles around and breaks shit CONSTANTLY when exposed to different things. its an actual trainwreck in a constant state of slamming shit into other shit until shit happens. like given, plants in general have weird genomes and like, i can understand that and accept that, but this is actually fucking ridiculous. to put this in perspective, roughly44% of the human genome is transposons or transposon-like elements. take that amount and double it and you have about the same amount of genomic chaos as maize. i’ve said it before and i’ll say it again:
the maize genome is a goddamn build-a-bear workshop and it scares me
EDIT: @thecrystalmadness brought up a good point in the tags that the source study for the percentage of the human genome statistic points out that although 44% of the human genome is structurally transposons, less that 0.05% are considered by the study to be active elements, which reflects how I need to be sure I’m reading all the sources I reference, not just the plant-related ones is a really interesting idea when we think about the maize genome; maybe the reason the maize we look at now is remotely consistent is because many of them have long since been disabled or silenced?
I tried digging a bit to see if I could find a similar study on general activity for Maize and didn’t find anything outside specific studies on families of genes, but let’s not forget that the maize genome has an entire database just for its transposons. In the intro, the database notes that the Maize is, “recognized as having the most dynamic TE component,” of most, if not all, higher eukaryote organism and that “As such, it is the organism of choice for understanding how TEs contribute to gene and genome evolution”. so whatever that number of active elements is, it’s significant enough to have affected how the species responds to many different kinds of evolutionary pressures and is indeed quite, how do u say, fucking high and very intimidating
The Cosmovital Botanical Gardens of Toluca, Mexico are known for their stunningly beautiful stained-glass windows, and provide a stirring example of ways that a city can find beautiful re-use for its built infrastructure.
Designed in art nouveau style by engineer Manuel Arratia, the building was originally constructed in 1909-1910 as the 16th de Septiembre Market. Over time, Toluca outgrew the market’s capacity, and it was closed in 1975. Debates over what to do with the space ensued: some suggested it be demolished and replaced with an open plaza, or sold to private interests to convert into offices. Local artist Leopolodo Flores worked with Yolanda Sentíes (the city’s first woman mayor) to gather support around converting the metal-and-glass upper structure into a space for art:
Flores envisioned something magnificent for the space. He saw a huge stained glass mural encircling the entire building and running across the ceiling. Below and within its confines he proposed a botanical garden. The art would show the relationship between man and the universe, the flora that which places man in his ecological environment.
Over the next four years, work continued to clean off seven decades of grime, reinforce structural integrity, and construct the vast mural. It opened to the public in 1980, though battles in local government meant that the ceiling was only finished in 1990.
Flores and sixty artisans worked for three years, from 1978 to 1980. The window-mural consists of 71 modules which cover an area of about 3,200 meters square. The work uses approximately 75 tons of metal supports, 45 tons of blown glass and 25 tons of lead to join the about 500,000 glass pieces, which range in size from 15 to 45 cm. Twenty eight different colors of glass were used, most of which came from Italy, Germany, France, Belgium, Japan, Canada and the United States. On the north side of the building, blues dominate, with brighter colors on the south side. The sun is placed on the east side. The windows are the largest of their kind in the world.
Each year on the spring equinox, the sun aligns with the Hombre Sol. This annual event lasts about twenty minutes in the late afternoon and is celebrated with a classical music concert, timed to the passing of the sun.
The Hombre Sol has come to be taken as a semi-official symbol of the city and state. At present only five percent of visitors are foreigners, but perhaps that might change.
Kihaku-Gato's Garden Blog (tumblr import) 