Plants perform a wonder that has attracted the admiration of scholars from ancient Egypt, Greece and Rome to modern times: the ability to reproduce mathematically perfect patterns. This ability, called phyllotaxis, can be described mathematically with the Fibonacci Series and the Golden Angle. The beautiful spirals in sunflowers, artichokes, cacti, dandelion heads and other plants continue to fascinate children and adults today, but those are not the only examples. Leaves on a stem can emerge in phyllotactic patterns like a spiral staircase, and depending on the environment, plants can switch patterns at different stages in development. Scientists have learned a lot about the players in the phyllotaxis game, but still do not understand the script. The details of how genes and proteins produce the patterns remain elusive. In Current Biology,1 French biologists Jean-Christophe Palauqui and Patrick Laufs recounted some of the theories that have tried to explain phyllotaxis. Scientists know that the plant hormone auxin becomes concentrated in the shoot meristem where new organ primordia emerge, and that the PIN1 auxin transporter is able to polarize the localization of auxin. New work reported in the same issue of Current Biology implicates the PLETHORA (PLT) gene family, known to be active with root formation, with the processes going on in the meristem. Tinkering with the players can enhance or inhibit pattern formation. Just how these players interact, though, is not well understood. It’s not a simple case of gene turning on protein turning on hormone; each of the players signal each other back and forth in a complex choreography. In addition, the PLT genes seem able to stimulate mechanical forces in the primordia by the way they regulate PIN1 polarity and hence auxin distribution. There are also time delays between gene expression and downstream effects, such as 4 hours from the time PLT genes activate to the time PIN1 transcript levels are seen to increase. But then, auxin level can also feed back to regulate PIN1 expression. It appears, therefore, that the intra-player signaling is indirect and complex. The authors stated that the bewildering interactions of these players keeps biologists busy: “Elucidating the mechanism underlying PLT-mediated control of phyllotaxis will be challenging and likely depend on quantitative descriptions and modeling of PLT expression, PIN1 levels and polarization, auxin distribution, growth and mechanics,” they said. Even if these problems are solved with mechanistic theories some day, questions may still remain about how a seed with no phyllotaxis results in a mature plant with it. And beyond that, philosophers of aesthetics may continue to ponder how plants – and many other phenomena in nature unrelated to them, like spiral galaxies, hurricanes, conch shells, and the cochlea in the human ear – reproduce “divine proportions” that humans find beautiful (see article by Fred Willson at ICR and the 11/20/2003 entry). 1. Jean-Christophe Palauqui, Patrick Laufs, “Phyllotaxis: In Search of the Golden Angle,” Current Biology, Volume 21, Issue 13, R502-R504, 12 July 2011, DOI 10.1016/j.cub.2011.05.054. Explaining the mechanics of something does not explain its origin. You can understand how a robot on an assembly line works, and describe its structures and functions with flowcharts, equations and blueprints. That knowledge will not explain why it produces a Mercedes. Wikipedia trivializes the explanation as a consequence of natural selection, claiming that the solution was found within a decade of Darwin by Wilhelm Hofmeister. “Questions remain about the details,” the entry oversimplifies. If that were true, the scientists publishing in this week’s Current Biology would not remain baffled by it. The devil is often in the details. Hofmeister knew nothing of PIN1 and PLT, let alone the genetic code. His simplistic model of competing mechanical forces is so 1896; it cannot satisfy observers today, with our newer knowledge of genetic codes, proteins, and cell signals. If evolutionists do some day get all the mechanics worked out, the questions stated above will still remain. Considering that not all plants employ phyllotaxis, and that the patterns seem unnecessary for survival, unguided evolution reduces to an empty hand-waving story that “amazing stuff happens sometimes.” The same criticism can be leveled at any explanation employing impersonal, material causes. Take a deeper look at that sunflower. Here is a natural wonder that calls out for better science, deeper philosophy, and perhaps most of all, sound theology.(Visited 38 times, 1 visits today)FacebookTwitterPinterestSave分享0
Share Facebook Twitter Google + LinkedIn Pinterest Ryan Martin 10-16-17The forecast looks pretty nice this morning as we move into an extended period of dry weather. Clouds may take their own sweet time breaking up here in the short term as cooler air is in place after following the frontal boundary in yesterday. However, as you look at the surface map, this is one of those rare times that you see no significant front anywhere across the central and western US, only high pressure on the way. So, clouds will break up and move out, and we will see warmer, drier air in here eventually. Today will just be a transition day, with no new precipitation.The dry pattern continues tomorrow through Saturday. Temperatures will head back to normal by midweek and will be above normal to finish the week and for the weekend. Evaporation rates will be near maximum by midweek and with strong southwest breezes, we should see excellent dry down. Harvest should be able to ramp back up rather quickly, especially in areas that did not see as heavy of rain yesterday with the frontal passage. The map above shows temps compared to normal for this coming Saturday afternoon.We do have a minor front that looks to move through the state next Sunday. However, that front loses a lot of strength and most of its moisture before arriving. Therefore, we look for only a few hundredths to perhaps a tenth over about 30% of the state for next Sunday, and that will be far north. We expect only a wind shift and slightly cooler temps behind the front.Behind that system, we go back to dry weather for next week. No new rain on the way Monday through at least Thursday. In fact, it may be closer to the 28th-29th before a good front can move in. That front still has rain potential up to at least .75” over 80% of the state.So, a nice harvest window is about to unfold over the state. It may take a day or two to get things suitable, but then we should be able to run full through most of the rest of the month.
Stirring the Ram Mandir pot once again, Uttar Pradesh Chief Minister Yogi Adityanath on Friday exhorted his supporters to start preparing for the construction of a temple in Ayodhya with the same zeal with which they celebrated Ram Leela.Delivering his annual Vijayadashami speech in Gorakhpur, Mr. Adityanath said: “Along with the grandeur of the Ram Leelas, we should all also start preparing to build a grand temple in the same way in which grand Ram Leelas have been organised in the form of the temple,” Mr. Adityanath said. He, however, did not explain or clarify his remark, which was delivered in a winding sentence in Hindi. “I would appeal to all of you that along with the Leelas (enactment of the life) of Bhagwan Shri Ram, we must also incorporate his values into our lives and propagate it in the society,” said Mr. Adityanath.The CM said without Lord Ram, the path of public welfare would not be complete and hoped that his “grand ideal character” would inspire everyone.Mr. Adityanath, who is also the head priest of the Gorakhnath temple, participated in the customary Vijay Shobha Yatra from the temple.
A Dalit man on September 26 staged a sit-in along with his four children at the Siddharth Nagar district magistrate’s office, protesting against the alleged ouster of his children from the school for his inability to pay fees.The father, Shiv Kumar, told reporters that the Saraswati Shishu Vidya Mandir at Shohratgarh area in Siddharth Nagar ousted his children, Viraj (4), Yuvraj (8), Jyoti (10) and Chanchal (14) on August 30 for not paying the school fees. He said the school principal even made casteist remarks against him when he met him to explain his inability to pay the fees.“I also went to the police but my they did not register my complaint,” he said, adding he also wrote to the district magistrate and to Basic Education Minister Satish Dwivedi apprising them of the cancellation of his children’s admission from the school.“If my children do not get justice, I will sit on fast unto death,” he saidAsked about the incident, Basic Education Minister Satish Dwivedi told reporters that he would speak to the district magistrate on the issue and take requisite action, if the school administration is found guilty.