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Evolution of cereals and grasses
What are cereals and grains, and where do they come from?
A cereal is any grass – yes you read that correctly, grass – cultivated for the edible components of its grain.
Common grasses that produce these wonderful grains are wheat, rye, millet, oat, barley, rice, and corn.
Wheat is the most common grain producing grass.
(botanically, a type of fruit called a caryopsis), composed of the endosperm, germ, and bran.
The term may also refer to the resulting grain itself (specifically “cereal grain”).
Cereal grain crops are grown in greater quantities and provide more food energy worldwide than any other type of crop[1] and are therefore staple crops. Edible grains from other plant families, such as buckwheat, quinoa and chia, are referred to as pseudocereals.
All of the grains that we eat have been genetically modified by thousands of years of artificial selection. This includes all wheat, barley, rye, spelt and oats.
Paper 1: “Wheat: The Big Picture”, The Bristol Wheat Genomics site, School of Biological Sciences, University of Bristol
Wheat: The Big Picture – the evolution of wheat

Figure 2. Phylogenetic tree showing the evolutionary relationship between some of the major cereal grasses. Brachypodium is a small grass species that is often used in genetic studies because of its small and relatively simple genome.
Paper 2: Increased understanding of the cereal phytase complement for better mineral bio-availability and resource management
Article (PDF Available) in Journal of Cereal Science 59(3) · January 2013 with 244 Reads
DOI: 10.1016/j.jcs.2013.10.003

Fig. 1. Phylogenetic tree of cereals and selected grasses. PAPhy gene copy numbers are given for each species and key evolutionary events are indicated.
Paper 2
Genome-wide characterization of the biggest grass, bamboo, based on 10,608 putative full-length cDNA sequences.
Peng Z, Lu T, Li L, Liu X, Gao Z, Hu T, Yang X, Feng Q, Guan J, Weng Q, Fan D, Zhu C, Lu Y, Han B, Jiang Z – BMC Plant Biol. (2010)

Figure 2: Phylogeny of grasses inferred from concatenated alignment of 43 putative orthologous cDNA sequences. (A) Tree inferred from maximal likelihood method. Bayes inference yielded the same topology. (B) Tree inferred from neighbor joining method. Branch length is proportional to estimated sequence divergence measured by scale bars. Numbers associated with branches are bootstrap percentages. Arabidopsis was used as outgroup. Subfamily affiliation of the grasses is indicated at right.
Paper 3 Evolution of corn

Figure 1: The evolutionary stages of domestication and diversification.
From Evolution of crop species: genetics of domestication and diversification, Rachel S. Meyer & Michael D. Purugganan, Nature Reviews Genetics 14, 840–852 (2013) doi:10.1038/nrg3605
http://www.nature.com/nrg/journal/v14/n12/fig_tab/nrg3605_F1.html
Paper 4 text
Brachypodium distachyon: making hay with a wild grass, Magdalena Opanowicz, Philippe Vain, John Draper, David Parker, John H. Doonan
DOI: http://dx.doi.org/10.1016/j.tplants.2008.01.007

This next image is from Setaria viridis as a Model System to Advance Millet Genetics and Genomics.
By Huang, Pu & Shyu, Christine & Coelho, Carla & Cao, Yingying & Brutnell, Thomas. (2016) Frontiers in Plant Science. 7. 10.3389/fpls.2016.01781.

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Science of Jurassic Park
Jurassic Park is a 1993 film directed by Steven Spielberg. The first installment of the Jurassic Park franchise, it is based on the 1990 novel of the same name by Michael Crichton.
Next Generation Science Standards: Science & Engineering Practices
● Ask questions that arise from careful observation of phenomena, or unexpected results, to clarify and/or seek additional information.
● Ask questions that arise from examining models or a theory, to clarify and/or seek additional information and relationships.
● Evaluate a question to determine if it is testable and relevant.
● Ask and/or evaluate questions that challenge the premise(s) of an argument, the interpretation of a data set, or the suitability of the design
Science and engineering practices: NSTA National Science Teacher Association
Next Gen Science Standards Appendix F: Science and engineering practices
1. When did dinosaurs live? Investigate the geological eras.
Another view of the relationship between geological eras and the Earth’s strata.
2. What are chromosomes/genes/DNA nucleotides?
DNA is like an alphabet: Analogies to explain nucleotides, genes and chromosomes
3. How might DNA possibly be preserved for long periods of time?
4. What is the scientific premise of the film: How did they recreate ancient dinosaurs? Did they (according to the film) create dinosaurs at all?
5. According to the book & film, not enough intact DNA was recovered to create a true dinosaur. How then were the theme park dinosaurs created?
http://jurassicpark.wikia.com/wiki/Filling_the_sequence_gaps
6. Have scientists ever actually discovered preserved soft tissue, and/or protein, in dinosaur fossils?
http://www.livescience.com/41537-t-rex-soft-tissue.html
http://www.smithsonianmag.com/science-nature/dinosaur-shocker-115306469/?no-ist
https://student.societyforscience.org/article/more-dinosaur-bones-yield-traces-blood-soft-tissue
7. Have scientists ever actually discovered preserved DNA in dinosaur fossils?
http://www.livescience.com/23861-fossil-dna-half-life.html
http://www.sci-news.com/paleontology/science-dinosaur-dna-amber-01383.html
http://scitechdaily.com/researchers-calculate-that-dna-has-a-521-year-half-life/
http://www.nature.com/news/dna-has-a-521-year-half-life-1.11555
https://en.wikipedia.org/wiki/Ancient_DNA
8. Some scientists have proposed that we can realistically reverse engineer dinosaurs from living birds. What is their biological, and evolutionary reasoning for why this could make sense?
http://www.livescience.com/17642-chickenosaurus-jack-horner-create-dinosaur.html
Can Scientists Turn Birds Back Into Dinosaur Ancestors? National Geographic
TED Talks: Jack Horner on building a dinosaur from a chicken
9. How would these scientists actually go about doing this? (Summarize in a clearly written paragraph, describing several steps.)
Additional resources
Are Movies Science? DINOSAURS, MOVIES, AND REALITY Univ. of California Museum of Paleontology
Real-Life ‘Jurassic World’ Dinos May Be Possible, Scientist Says: LiveScience
Can scientists clone dinosaurs? How Stuff Works
Scrappy Fossils Yield Possible Dinosaur Blood Cells: National Geographic
DNA has a 521-year half-life, Nature (scientific journal)
The final nail in the Jurassic Park coffin. Research just published in the journal The Public Library of Science ONE (PLOS ONE)
Absence of Ancient DNA in Sub-Fossil Insect Inclusions Preserved in ‘Anthropocene’ Colombian Copal. (scientific journal)
Science of Jurassic Park: JurassicWikia
Book: The Science of Jurassic Park: And the Lost World Or, How to Build a Dinosaur
Egyptians, Genetics, Sociology and Race
From Nivenus, at Observation Deck:
When the cast of Exodus: Gods and Kings—Ridley Scott’s upcoming Biblical epic—was announced a lot of people made the complaint that it was overwhelmingly white, a move they decried as both inaccurate and racist. They were right. Unfortunately, in response a lot of people have peddled another historical (and racist) error: that the ancient Egyptians were black and that modern Egyptians are imposters…
…Cultures as different from one another (and Western Europe) as the Mongol Empire, northern India, Arabia, and Comanches have all been portrayed by white actors … because, again, the presumption is that a white actor is a blank slate within whom everyone can identify, including non-white people
…However, while the tendency usually is to whitewash historical peoples, the opposite also sometimes occurs. There is an increasing tendency I’ve noticed for some people, for example, to re-envision all of the ancient societies of the Old World as not simply non-white, but specifically “black.” Putting aside for a moment the fact that within Africa itself “black” is a largely meaningless term (there’s more genetic variety within Africa’s “black” population than the rest of the world combined), this is just simply false. The samurai were no more black than they were white. And neither were the ancient Egyptians.
That’s right, the ancient Egyptians weren’t black. They weren’t white either, mind you, but to presume that a culture has to be one or the other is to accept a racial dichotomy that white colonialists themselves invented for the purpose of sorting the world into “civilized” (white) and “savage” (colored) peoples. Most cultures in the world don’t really fit neatly into either category: are Latinos white or colored? The answer depends partially on who’s asking the question: most Latinos identify as white (both in the U.S. and Latin America) but most non-Latino Americans usually sort them as non-white.
The truth is that “white” is essentially a byword for “European” (sometimes northern European specifically) while “colored” basically just means everyone else. And these categories aren’t static or unchanging either. In 19th century Europe, various ethnic groups were sometimes sorted into “more” or “less” white groups. According to many British anthropologists, the Irish were “less white” than the English. According to the Nazis, Slavic-speaking peoples like Poles or Russians were “subhuman” non-Aryans. Today, virtually all of these groups are considered “equally” white (and Jews, who weren’t considered white at all, now often are).
This outdated way of talking about race was so prevalent and so dominant in academic circles that it’s been accepted as largely accurate, even by lots of non-white people. Instead of challenging the arbitrary lines in the sand 19th century racists drew up to sort people into those who were worthy of self-rule and those who weren’t, a lot of people have just flipped the idea on its head, arguing that the roots of all civilization are inherently “black” rather than “white,” as Eurocentric scholars claimed.
Which brings us to Egypt. For some reason or another—possibly because of the highly publicized discovery of Tutankhamun’s tomb in the 1920s, possibly because the Great Pyramid of Giza is one of the last remaining wonders of the ancient world—everyone wants to claim ancient Egypt for themselves….
What were the ancient Egyptians? Were they black or were they white?… Oddly, it’s occurred to relatively few people to look at how modern Egyptians think of themselves, because we have divorced ancient and modern Egypt in our minds as if they’re two completely unrelated cultures. …
…. what about how Egypt got invaded and conquered by a whole bunch of people, including the Arabs? Couldn’t that have impacted the Egyptians’ race? Well sure, that happened. Libyans, Nubians, Canaanites, Mesopotamians, Persians, Greeks, and Romans have all ruled Egypt at one point or another and the Arabs are the most recent bunch (not counting the Turks or the British). But the truth is that conquest only very rarely leads to a massive shift in the native population… genetic studies in Egypt back this up:
the genetic profile of modern Egyptians has been affected less than 15% by foreign admixture.
There’s also the fact that ancient Egyptians didn’t really perceive themselves as either “black” or “white.” Just look at the above painting from Pharaoh Seti I’s tomb. The top right group, with the palest skin are Libyans (Berbers), the next one over to the left are Nubians, followed by “Asiatics” (Mesopotamians).
The bottom central group are Egyptians. By their own perception Egyptians were neither particularly dark nor particularly pale, and given their xenophobic attitude towards outside cultures (which was fairly common for most ancient peoples) they would probably resent being sorted into either “race.”
So why does this matter? Why is it important that we acknowledge the Egyptians don’t fit into our constructed dichotomy of black vs. white, of European or African? Well, for one thing many modern Egyptians find it kind of offensive. Despite their modern self-identification as Arabs, most Egyptians still feel a strong claim to the historical legacy of their ancient forebears and find it pretty annoying when American scholars (and, black or white, it is mostly Americans) try to pigeonhole the pharaohs into one racial category or another for political purposes.
Secondly, it’s pretty clearly false as I’ve shown above. The ancient Egyptians were African, but that’s a pretty broad label, just like the word “Asian” includes within its meaning Turks, Indians, Samoyeds, Han Chinese, and Malays. There’s a lot of similarity between Egyptians and Nubians, that’s true. There’s also a lot of resemblance between Egyptians and Palestinians. They don’t fit neatly into one super-category or the other, not when you peel away the labels and look at the actual facts.
Egyptians Aren’t White… But They Aren’t Black Either
Also see Genetic variation, classification and race
Man Fails Paternity Test… Because Man’s Unborn Twin Is The Biological Father Of His Son
October 26, 2015 | by Justine Alford
Prepare to have your mind blown. This is the fascinating case study of a man who failed a paternity test because part of his genome actually belongs to his unborn twin. This means that the genetic father of the child is actually the man in question’s brother, who never made it past a few cells in the womb.
Yes, this sounds completely crazy and like a headline you might read in a trashy magazine. But before you write it off as that, let’s go into some more details.
It all starts off with a couple in the U.S. who were having trouble conceiving their second child. They decided to seek help and went to a fertility clinic, where eventually intrauterine insemination was performed. This involves washing and concentrating sperm before inserting it directly into the uterus of a woman around the time of ovulation to boost the chances of fertilization.
The assisted conception worked, and nine months later the happy couple welcomed a baby boy into the world. But then things started to take a turn for the weird. Testing revealed that the child’s blood type didn’t match up with his parents’.
“Both parents are A, but the child is AB,” Barry Starr from the Department of Genetics at Stanford University told IFLScience. “There are rare cases where that can happen, but their first thought was that the clinic had mixed up sperm samples.”
The couple therefore decided to take a standard paternity test, which to their dismay revealed that the man was not the child’s father. So they took another test, but the results were the same. At this point, mixing up samples didn’t seem too far-fetched, but the clinic had only dealt with one other intrauterine insemination at the same time as this couple, which involved an African-American man, and given the child’s appearance this didn’t match up.
This was when Starr was contacted by the couple’s lawyer, who suggested that they take a more powerful test: the over-the-counter 23andMe genetic service. This was because this particular test is good at looking at family relationships. The results that came back were pretty surprising, suggesting that the child’s father was actually his uncle, the man’s brother.
At this point, Starr’s team decided to delve a little deeper, with the idea that the man could possibly be a “human chimera,” i.e. an individual with different genomes. It’s actually not uncommon for multiple fertilizations to happen in the womb even when only one child is born. What can sometimes happen is two independent early embryos, at this stage just clumps of cells, actually fuse together and go on to develop normally as a single individual.
To test this theory, DNA samples were taken from both the cheek of the father, which was used for the original paternity tests, and also his sperm. Once again, the cheek cells didn’t match up with the child, but the sperm sample told a different story.
Supporting the human chimera idea, what they found was a “major” genome, accounting for roughly 90% of the sperm cells, and a “minor” genome that only represented about 10%, Starr explained. The major genome matched up with the cheek cells, but the minor genome was consistent with the child’s DNA.
“So the father is the fusion of two people, both the child’s father and uncle. That’s wicked cool,” said Starr.
Original article: Man Fails Paternity Test Because Man’s Unborn Twin Is The Biological Father Of His Son
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What is a chimera?
A genetic chimerism – or chimera – (from the creature Chimera in Greek mythology) is a single organism composed of genetically distinct cells. This can result in:
male and female organs, two blood types, or subtle variations in form.
Animal chimeras are produced by the merger of multiple fertilized eggs.
In plant chimeras, however, the distinct types of tissue may originate from the same zygote, and the difference is often due to mutation during ordinary cell division.
Normally, chimerism is not visible on casual inspection; however, it has been detected in the course of proving parentage.
Another way that chimerism can occur in animals is by organ transplantation, giving one individual tissues that developed from two genomes. For example, a bone marrow transplant can change someone’s blood type.
{Adapted from Wikipedia, Chimera, October 2015}
This diagram shows two ways that a human can be born a chimera.
The article is describing the second/lower case.







