Friday, March 20, 2020

Pea (Pisum sativum L.) Domestication - The History of Peas and Humans

Pea (Pisum sativum L.) Domestication - The History of Peas and Humans Pea (Pisum sativum L.) is a cool season legume, a diploid species belonging to the Leguminosae family (aka Fabaceae). Domesticated about 11,000 years ago or so, peas are an important human and animal food crop cultivated throughout the world. Key Takeaways: Domesticated Peas Peas are one of several legumes, and a founder crop domesticated in the Fertile Crescent about 11,000 years ago.  The earliest human consumption of wild peas was at least 23,000 years ago, and perhaps by our Neanderthal cousins as long ago as 46,000 years ago.  There are three modern species of peas, and they are very complex genetically and their precise domestication process has yet to be figured out.  Ã‚   Description Since 2003, global cultivation has ranged between 1.6 to 2.2 million planted hectares (4–5.4 million acres) producing 12–17.4 million tons per year. Peas are a rich source of protein (23–25%), essential amino acids, complex carbohydrates, and mineral content like iron, calcium, and potassium. They are naturally low in sodium and fat. Today peas are used in soups, breakfast cereals, processed meat, health foods, pasta, and purees; they are processed into pea flour, starch, and protein. They are one of the eight so-called founder crops and among the earliest domesticated crops on our planet. Peas and Pea Species Three species of peas are known today: Pisum sativum L. extends from Iran and Turkmenistan through anterior Asia, northern Africa, and southern EuropeP. fulvum is found in Jordan, Syria, Lebanon, and IsraelP. abyssinicum is found from Yemen and Ethiopia Research suggests that both P. sativum and P. fulvum were domesticated in the Near East about 11,000 years ago, likely from P humile (also known as Pisum sativum subsp. elatius), and P. abyssinian was developed from P. sativum independently in the Old Kingdom or Middle Kingdom Egypt about 4,000–5,000 years ago. Subsequent breeding and improvements have resulted in the production of thousands of pea varieties today. The oldest possible evidence for people eating peas is that of starch grains founded embedded in the calculus (plaque) on Neanderthal teeth at Shanidar Cave and dated about 46,000 years ago. Those are tentative identifications to date: the starch grains are not necessarily those of P. sativum. Undomesticated pea remains were found at Ohalo II in Israel, in layers dated about 23,000 years ago. The earliest evidence for the purposeful cultivation of peas is from the Near East at the site of Jerf el Ahmar, Syria about 9,300 calendar years BCE [cal BCE] (11,300 years ago). Ahihud, a Pre-Pottery Neolithic site in Israel, had domestic peas in a storage pit with other legumes (fava beans, lentils, and bitter vetch), suggesting they had been cultivated and/or used for the same purpose. Pea Domestication Pisum sativa (Sugar Snap peas). Jenny Dettrick / Moment / Getty Images Archaeological and genetic research indicates that the pea was domesticated by people purposefully selecting for peas that had a softer shell and ripened during the wet season. Unlike grains, which ripen all at once and stand up straight with their grains on predictably sized spikes, wild peas put out seeds all over their flexible plant stems, and they have a hard, water-impermeable shell that allows them to ripen over a very long period of time. While long producing seasons may sound like a great idea, harvesting such a plant at any one time is not terrifically productive: you have to return time and time again to collect enough to make a garden worthwhile. And because peas grow low to the ground and seeds arise all over the plant, harvesting them isnt particularly easy either. What a softer shell on the seeds does is allow the seeds to germinate in the wet season, thereby allowing more peas to ripen at the same, predictable time. Other traits developed in domesticated peas include pods that dont shatter on maturity- wild peapods shatter, scattering their seeds out to reproduce; we would prefer that they wait until we get there. Wild peas have smaller seeds, too: wild pea seed weights range between .09 to .11 (about 3/100ths of an ounce) grams and domesticated ones are larger, ranging between .12 to .3 grams, or 4/100th to a tenth of an ounce. Studying Peas Peas were one of the first plants studied by geneticists, starting with Thomas Andrew Knight in the 1790s, not to mention the famous studies by Gregor Mendel in the 1860s. But, interestingly enough, mapping the pea genome has lagged behind other crops because it has such a large and complex genome. There are important collections of pea germplasm with 1,000 or more pea varieties located in 15 different countries. Several different research teams have begun the process of studying pea genetics based on those collections, but the variability in Pisum has continued to be problematic. Israeli botanist Shahal Abbo and his colleagues built wild pea nurseries in several gardens in Israel and compared the grain yield patterns to those of domesticated pea. Selected Sources Abbo, S., A. Gopher, and S. Lev-Yadun. The Domestication of Crop Plants. Encyclopedia of Applied Plant Sciences (Second Edition). Eds. Murray, Brian G., and Denis J. Murphy. Oxford: Academic Press, 2017. 50–54. Print.Bogdanova, Vera S., et al. Cryptic Divergences in the Genus Pisum L. (Peas), as Revealed by Phylogenetic Analysis of Plastid Genomes. Molecular Phylogenetics and Evolution 129 (2018): 280–90. Print.Caracuta, Valentina, et al. Farming Legumes in the Pre-Pottery Neolithic: New Discoveries from the Site of Ahihud (Israel). PLOS ONE 12.5 (2017): e0177859. Print.Hagenblad, Jenny, et al. Genetic Diversity in Local Cultivars of Garden Pea (Pisum Sativum L.) Conserved ‘on Farm’ and in Historical Collections. Genetic Resources and Crop Evolution 61.2 (2014): 413–22. Print.Jain, Shalu, et al. Genetic Diversity and Population Structure among Pea (Pisum Sativum L.) Cultivars as Revealed by Simple Sequence Repeat and Novel Genic Markers. Molecular Bi otechnology 56.10 (2014): 925–38. Print. Linstdter, J., M. Broich, and B. Weninger. Defining the Early Neolithic of the Eastern Rif, Morocco – Spatial Distribution, Chronological Framework and Impact of Environmental Changes. Quaternary International 472 (2018): 272–82. Print.Martin, Lucie. Plant Economy and Territory Exploitation in the Alps During the Neolithic (5000–4200 cal BC): First Results of Archaeobotanical Studies in the Valais (Switzerland). Vegetation History and Archaeobotany 24.1 (2015): 63–73. Print.Sharma, Shagun, et al. Quality Traits Analysis and Protein Profiling of Field Pea (Pisum Sativum) Germplasm from Himalayan Region. Food Chemistry 172.0 (2015): 528–36. Print.Weeden, Norman F. Domestication of Pea (Pisum Sativum L.): The Case of the Abyssinian Pea. Frontiers in Plant Science 9.515 (2018). Print.

Wednesday, March 4, 2020

Word Choice Inflict vs. Afflict - Proofeds Writing Tips

Word Choice Inflict vs. Afflict - Proofeds Writing Tips Word Choice: Inflict vs. Afflict The verbs inflict and afflict are spelled similarly and, indeed, closely related in meaning, since both refer to pain or suffering. However, these terms are also opposites in some senses, so it is vital not to confuse them in your written work. Read on to find out more. Inflict (Cause Suffering) The verb inflict means cause or impose something unpleasant, usually pain or suffering. Inflict is a transitive verb, so always takes a direct object (the thing being inflicted) and usually requires an indirect object (the thing being affected): The rider inflicted whip wounds upon the horse. In the sentence above, the direct object of inflict is whip wounds, while the indirect object is the horse being whipped. You can also use inflict to mean imposing something unwelcome, often an opinion. In this case, we could use it in a sentence like this: At Christmas, Aunt Emily inflicted her extreme views about child discipline upon our entire family. Afflict (Suffer from Something) The verb afflict means distress or affect something adversely. It is often used passively rather than actively, meaning that we usually say that someone has been afflicted by something. For example: Many people in the region were afflicted by a contagious disease. You can use afflict with the active voice by placing the subject of the sentence before the verb: Whooping cough usually afflicts those who have not been immunized. Something that afflicts a victim is an affliction. This means a state of pain or suffering. You can also use afflict and affliction figuratively, or sometimes sarcastically, to exaggerate the suffering involved in something: We had to cancel our holiday because we’re too busy. Please sympathize with us in our affliction. Inflict or Afflict? These words could both be used to describe the same situation, depending on the perspective adopted. However, because of this, it is essential not to confuse them in your work. Remember, to inflict is to cause somebody pain, suffering or injury. To be afflicted is to be the victim of pain, suffering or injury. If you would like more advice, or to have a 500-word sample of your work proofread for free, get in touch with Proofed today!