Brother Gregory: Gene One Page 4
"As in separate pods, so did the distribution of the characters vary in separate plants. Did it not?" asked Brother Timothy, his voice like silk. It is easy to ask good questions when you already know the answers. He was sitting on the edge of his seat and staring directly at the increasingly uncomfortable Mendel.
"Somewhat," Mendel admitted reluctantly, shuffling his notes and not looking at Brother Timothy directly.
Like an anthropologist encountering a new behavior in a study population, teacher Makytta was watching a ritual of science; the ruthless tearing down of a presentation by an opponent in the audience. Regardless of its merits, any scientific position is always open to attack. Most outside the profession thinks that these attacks are in the interests of truth, for the elimination of falsehood, and are essential parts of the scientific method. They rarely are. Ego and ambition are greater driving forces in the pursuit of new discoveries than idealistic searches for the truth.
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Chapter Eleven
More Questions
"Let me remind you of some of the data you presented earlier, Brother Gregory," continued Brother Timothy. "You reported extremes in the distribution of the two seed characters in one plant." He smiled, and went on, "In experiment number one you said you found an instance of 43 round and only 2 angular, and another of 14 round and 15 angular seeds. Am I correct?" Mendel could just nod, he had indeed reported such numbers, but only Brother Timothy had understood them. "And in experiment number two there was, not only a case of 32 yellow and only 1 green seed, but also one of 20 yellow and 19 green, was there not?" Again the nod. "According to my calculations, none of these data give ratios of 3:1, the way you reported. Do you have an explanation?"
After thinking for a moment, Mendel replied, "The two experiments you mention are important for the determination of the average ratios, because with a smaller number of experimental plants they show that very considerable fluctuations may occur. [see footnote]“
"Ahh," snorted Brother Timothy, interrupting Mendel's answer, another tactic in scientific debate. "And how easy was it to determine the exact color of the seeds? It has been my experience that there is a lot of subjective judgment required."
"Very true, Brother Timothy," said Mendel, "In counting the seeds especially in experiment number two, some care was required. In some of the seeds of many plants the green color of the albumen is less developed, and at first may be easily overlooked."
"Don't you find that makes the impartial determination of your results hard to accept?"
"The cause of this partial disappearance of the green coloring has no connection with the hybrid-character of the plants, as it likewise occurs in the parental variety," explained Mendel, becoming a bit frustrated. Didn't they get it? None of these trivial details mattered, they were all peripheral to the central argument and the nature of the results.
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Chapter Twelve
Postponement
At this point, a new voice was heard. From the back of the room a monk rose to his feet and came to Mendel's defense.
"Brother Gregory," he said firmly, "Is not this peculiarity confined to the individual and is not inherited by the offspring?"
All necks turned to view the speaker. They saw a man of about Mendel's age, but shorter and thinner. On top of a triangular head his thin gray hair was parted perfectly down the middle and combed flat to both sides. Brother Joseph Lindenthal was normally a quiet man who was perfectly happy helping Mendel with his plants and experiments. Only once in his life had he defied his Abbot, and on that occasion he had been under the influence of Brother Matthew.
Mendel seized on the reprieve, "Ahh, yes, thank you Brother Joseph, in luxuriant plants this appearance was frequently noted. Seeds which are damaged by insects during their development often vary in color and form."
"But it does not influence the experienced experimenter, does it?" insisted Brother Joseph, determined to end the humiliation of his friend and co-experimenter.
"Indeed not," said Mendel, "with a little practice in sorting, errors are easily avoided. It is almost superfluous to mention that the pods must remain on the plants until they are thoroughly ripened and have become dried, since it is only then that the shape and color of the seed are fully developed."
But the damage had been done and Brother Timothy was not going to let Mendel off that lightly. "Herr Grunewald," Brother Timothy turned to the German textile manufacturer, "am I not right in thinking that the numbers of plants reported in experiments one and two are too small to have statistical significance?" This question woke up the distinguished member, who had been showing more interest in his cigar than in the latter part of the paper.
"Hummmp, indeed yes," he replied, "the numbers, yes, the numbers. I warned you Brother Gregory." He wagged his gloved finger at the unfortunate Monk. "You ignore the numbers at your peril. How can you determine anything of significance from 43 peas?" He looked around the audience for confirmation. About half the faces looking back at him knew enough about mathematics and the importance of statistics to nod in agreement. Mendel's numbers in experiments one and two had been far too small to allow for serious deductions. Other faces showed doubt. They belonged to the naturalists, like Napp, who were more interested in the biological consequences of Mendel's discoveries and were increasingly dismayed that the discussion was bogging down in the arcane world of fractions and ratios. Neither group, however, seemed pleased at the current position of Mendel's paper and his results.
Sensing the mood of the members, Vice President Theimer jumped to his feet and faced the audience. "Yes, indeed, Brother Gregory has given us a lot to think about this evening." He rubbed his hands together, "I have a suggestion. Today is February 8th, there is no speaker scheduled for our meeting on March 8th, why don't we ask Brother Gregory to return on that date, with all his data, and we will hear his reply to Brother Timothy and Herr Grunewald?" There was a murmur of agreement around the room, accompanied by louder sounds of agreement from Brother Matthew and teacher Makytta. It was cold and most of the audience just wanted to go home. For the rest, they needed time to think about what Mendel had said and what it all meant. Perhaps next month the monk would clarify some of the issues raised by Brother Timothy. It was a good solution.
"Good, then we are adjourned for this evening," said Theimer and began to clap his hands in reward of the speaker. A few others joined in, but their applause was almost drowned out by the scraping of chairs as stiff listeners finally got to their feet. Several members of the audience came forward to speak to Mendel. Their traditional phrases of gentle congratulation were noticeably weak. Brother Matthew, Thomas Makytta and Brother Joseph clustered round him and their praise was clear and most sincere. Even Grunewald made a move to approach Mendel, but his progress was blocked by Brother Timothy who intercepted him and began to talk about Monastery business.
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Chapter Thirteen
Until Next Time
"Well done, Brother Gregory," said Brother Matthew over enthusiastically, "a good presentation. I particularly liked the part where you described how the pea plants were grown." Ruefully, Mendel smiled back at his friend.
"Thank you Brother Matthew, it is kind of you," he said softly, "but I feel that your opinion is not shared by many others." He looked around the room where small groups of men were huddled in conversation that he was sure had nothing to do with his talk. Often, after a controversial presentation, members of the audience would debate one point or another for several hours, moving the argument to the local coffee shop when they were ejected from the Realschule. But not tonight. Most of the members were now talking politics or business, not plant hybridization.
Breaking off from one such group, Abbot Napp approached the four lonely figures. Holding out his han
d to Mendel, who took it firmly, he said, "Well done Brother Gregory, you spoke clearly and your voice carried well. I heard every word." He drew Mendel closer to him and put an arm around his shoulders. "But a word of advice. Next time have your data and your conclusions more firmly drawn. Do not hesitate in your presentation and be prepared to defend even the most obvious of points." Mendel agreed silently.
"Brother Timothy is ambitious," went on Napp, "but he is a good scientist, and you should listen to him." The Abbot felt obliged to apologize for his protégé’s behavior. "In science, as in life, there are many different types of players. Some, like your friends here," and he acknowledged Bothers Matthew and Joseph, "will agree with you no matter what you say. And some," here he nodded in the direction of Brother Timothy, "will attack you just because your success in some way lessens them." He paused to see if Mendel was following his advice.
"To them, your data, correctly interpreted, is not just a discovery or an advancement of God's truth, it is a minor victory for you, and a loss for them in a battle they fight every day to be perceived as either the first or the best." Mendel looked puzzled at these last remarks, so Napp tried to make his point more clearly. "Those who succeed, at least think they have succeeded in science, have very large egos. Few are good scientists. Large egos need constant feeding and the nourishment they need the most is praise and the perception of power or authority." Once again the humble monk was having difficulty in following his Abbot.
Napp shook his head. It would take more than one lesson to educate this gentle man who still believed that honesty and truth were the two most important virtues in science. Perhaps he would get his second lesson at the next presentation in March, but Napp was determined to make sure he was better prepared the next time.
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Afterword
This story is fiction; but scientific fiction based on fact. Johann "Gregor" Mendel, Thomas Makytta, Mateous Klacel (Brother Matthew), Joseph Lindenthal, C. Romer and Abbot Cyril Napp were all real people who lived when and where this story places them. Herr Grunewald is fictional, but typical of a new kind of industrialist who was becoming more and more common in the 19th century, especially in England.
Brother Timothy is the interesting invention. Mendel historians will recognize a lot of similarities between my 'Brother Timothy' and a real monk who was a contemporary of Mendel, however this character is also fictional
I have based this story, and the ones to come, as much as possible on the known facts about Gregor Mendel, who did indeed present his research to the Brno Society of Natural Sciences In February and March of 1865, almost without any effect or without leaving any lasting impression.
Science, and the people who perform these arts, are rarely presented accurately in the popular media, i.e. newspapers, television and, of course, movies and TV dramas. This is a great pity as these crude stereotypes badly warp our perceptions of the men and women who carry out research and distorts the very nature of this critical human process. (I don’t think I have ever seen a movie that accurately shows is audience how real science is performed!). Modern human culture and society are now totally dependent on the fruits of scientific research (look at the scientific technology behind the device you are using to read this!!), yet people today know more about Superman than they do about Jonas Salk, Isaac Newton or Gregor Mendel. This is a great pity. In writing these stories about “Brother Gregory” therefore, I have tried to combine scientific accuracy, and a fair presentation of the nature of science, with narrative tales that can compete with popular fiction. I hope you agree.
In the next Brother Gregory story Herr Otto Grunewald delivers his cigars and some surprises. Of course, Brother Timothy also plays an active role.
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Footnotes
Artificial Fertilization
Mendel's experiments were based on the concept that each parent in a genetic cross contributed an equivalent 'transmission element' to the offspring. To test this idea Mendel crossed plants exhibiting one form of a character, with plants exhibiting the other form, and repeated this experiment for each of the seven characteristics he felt was unique enough to be unambiguous.
He probably guessed that the 'element' for seed color came in (at least) two forms; yellow and green, or flower color; white and purple. Plants showing one of these forms contained two identical 'elements' (both purple flower 'elements', for example), but only passed one of these two 'elements' onto their offspring during fertilization.
So he tested this idea by artificially fertilizing one form of a plant (purple flowers) using 'elements' from a plant showing the alternate form (white flowers). This is was carried out by brushing the pollen from one plant onto the stigma of the other. In this way the male 'element' from the pollen eventually joins with the female 'element' in the eggs. But what if the 'male element' was not equivalent to the 'female element'?
To test whether his results depended on which plant was donating the pollen (or egg), Mendel always carried out each experiment in two ways, something called a "reciprocal cross". Using the same plants and the same forms of each trait, one plant first acted as pollen donor and then, in the second "reciprocal" experiment, as an egg donor. Note: Mendel called the egg donors "seed bearers".
Every summer, for several years, Mendel would start his experiments. He had two options. First, he did nothing and let the Pisum plants self-fertilize. The flower structure is such in this species that pollen from the stamens will fall directly onto the pistil. All the reproductive organs of the flower being inside the protective covering of the keel. Artificial fertilizations were performed by opening the keel, and using a small, delicate paint brush to bring the tiny pollen grains from one plant to the stigma of another.
Then he waited for the pea pods to grow so he could collect the seeds, store them over the winter, plant them the next spring, and wait for the results. He must have been very patient!
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Differentiating characters
Mendel realized that the plants he was breeding contained two elements, which we now call genes. These genes can be damaged by normal and artificial mutagenesis to produce variants which in turn change the appearance of the plant or some part of the plant.
If we represent the gene for normal flower color using a letter "R", a "pure breeding" plant that always produced offspring with normal flowers would contain two of these genes, thus RR.
Similarly, if we represent a damaged or mutant gene using the letter "r", a plant with two of these genes, rr will show the altered (mutant) flower color.
This was Mendel's starting material. Using plants like these he began his "hybridization" experiments to see how these genes would be transmitted into the hybrids and beyond. From the patterns of inheritance he observed, he was able to deduce not only what genes the plants carried, but the "laws" governing their transmittal.
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The Civil War
While Mendel was growing his peas, a continent and an ocean away in the United States the American Civil War was reaching a state of crisis.
Northern victories at Vicksburg and Gettysburg in July 1863 had been a turning point in the war.
Lincoln made Grant commander-in-chief of all Union forces and in May 1864 Grant advanced deep into Virginia. At the three-day Battle of the Wilderness armies of the North and South clashed with heavy losses on both sides. Grant refused to retreat. Instead, he attempted to outflank Lee, and the battle enter days of bloody trench warfare.
In the West General William T. Sherman invaded Georgia, outmaneuvering several smaller Confederate armies. Atlanta was occupied and Sherman then marched to the Atlantic coast, destroying railroads, factories, warehouses and everything else in his path. His army looted the countryside for food.
In February
1865, as Mendel was giving his talk in Brno, Sherman was marching northward, and by the time Mendel had finished speaking Sherman had surrounded Charleston, South Carolina. This was of particular significance since this was where the first shots of the Civil War had been fired. Sherman was determined to destroy the morale of the South and did so with brutal efficiency.
Meanwhile, Grant was laying siege to Petersburg, Virginia, and in March 1865 (as Mendel was giving the second part of his talk), Lee abandoned both Petersburg and Richmond, the Confederate capital. He attempted to retreat south, but he had left it too late. On April 9, 1865, surrounded by huge Union armies, the Confederate General surrendered to Grant at Appomattox Courthouse. Some scattered fighting continued elsewhere but essentially the Civil War was over.
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Controls
Mendel's work and the results he reports are unique and special for many reasons, including the obvious one that he was the first to unambiguously demonstrate the 'particulate' nature of the 'transmission elements'. But Mendel was ahead of his time in another way. Other botanists had carried out genetic crosses, but none of them had performed any control experiments. Mendel's use of control experiments was original. There was no precedent for this in any of the scientific literature he would have read, and none of his mentors apparently thought it important to control for other possible complicating factors.
The significance of a parallel set of experiments is clear from Mendel's work. For example, although his audience probably went to sleep as he tried to explain it, his use of the indoor results (carried out in a greenhouse) to dismiss certain outdoor results made it possible to attribute anomalous behavior to the work of beetles (which also enjoy a good meal of pollen). He knew all about the risk of false fertilizations in which the pollen donor is not known, and went to considerable extra lengths (and effort) to eliminate, or at least account for, any such false fertilizations. Without these controls, Mendel would have been at a loss to explain the behavior of his 'elements'.