Tue, 23 August 2016
Thanks to The Great Courses Plus for sponsoring this video. You can start your subscription with a free one-month trial today by visiting http://ow.ly/Yq7c302duah Hybrid animals are infertile because of the way their sex cells form. But sometimes, life finds a way. FYI: We try to leave jargon out of our videos, but if you want to learn more about this topic, here are some handy keywords to get your googling started: Species featured in this video: Credits (and Twitter handles): Image Credits: Liger Hercules - Ed Quinn Zonkey - Flickr user Leogirly4life Cama - TaylorLlamas.com Beefalo - Noah's Ark Animal Like our videos? Also, say hello on: And find us on itunes: https://goo.gl/sfwS6n If you liked this week’s video, we think you might also like these things: References: Ryder, O., Chemnick, L., Bowling, A., Benirschke, K. (1985). Male mule foal qualifies as the offspring of a female mule and Jack donkey. Journal of Heredity 76 (379-381). Retrieved from http://jhered.oxfordjournals.org/content/76/5/379 C.J. Zhao, Y.H. Qin, X.H. Lee, Ch. Wu (2006). Molecular and cytogenetic paternity testing of a male offspring of a hinny. Journal of Animal Breeding and Genetics,123: 403-405. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/17177697 Bucholz (2013). Colorado miracle mule foal lived short life, but was well-loved.The Denver Post. Retrieved from http://www.denverpost.com/2013/08/16/colorado-miracle-mule-foal-lived-short-life-but-was-well-loved/ Millon, L. (2016). Personal Communication. Antczak, D. (2016). Personal Communication. |
Mon, 15 August 2016
Farming erodes soil 50 times faster than it forms. We can change that, but will we? Thanks to http://www.soylent.com/earth for sponsoring this video! Thanks also to our supporters on https://www.patreon.com/MinuteEarth : Credits (and Twitter handles): _________________________________________ Like our videos? Also, say hello on: And find us on itunes: https://goo.gl/sfwS6n If you liked this week’s video, we think you might also like these things: FYI: We try to leave jargon out of our videos, but if you want to learn more about this topic, here are some handy keywords to get your googling started: Agricultural Soil Erosion: the wearing away of a field's topsoil by the natural physical forces of water and wind or through forces associated with farming activities, such as tillage. http://goo.gl/d0Ciwk Conservation tillage/agriculture: a soil cultivation method in which fields are not ploughed & the previous year's crop residues are left on fields before and after planting the next crop, to reduce soil erosion and runoff. http://goo.gl/8aoizx, http://goo.gl/jmj8Ic Soil: the upper layer of earth, in which plants grow; a dark, damp, gas-filled structure of minerals and organic matter formed by degrading rocks and decomposing organisms. http://goo.gl/Q6JOrH References: A Landowner’s Guide to Prairie Conservation Strips. Accessed May 5, 2016. https://goo.gl/fN65MA Antón, S. C., & Steadman, D. W. (2003). Mortuary patterns in burial caves on Mangaia, Cook Islands. International Journal of Osteoarchaeology, 13(3), 132-146. http://goo.gl/SIiMxy FAO and ITPS. (2015). Status of the World’s Soil Resources (SWSR) – Main Report. Food and Agriculture Organization of the United Nations and Intergovernmental Technical Panel on Soils, Rome, Italy. http://goo.gl/fxPJi0 Kirch, P. V. (1997). Microcosmic histories: Island perspectives on" global" change. American Anthropologist, 99(1), 30-42. Montgomery, D. R. (2007). Soil erosion and agricultural sustainability. Proceedings of the National Academy of Sciences, 104(33), 13268-13272. http://goo.gl/Si9E6g Pimentel, D. (2006). Soil erosion: a food and environmental threat. Environment, development and sustainability, 8(1), 119-137. http://goo.gl/64FSCa Soil Building Systems. Pickup Truck Capacities. Accessed May 5, 2016. http://goo.gl/u7sPfQ Steadman, D. W., Antón, S. C., & Kirch, P. V. (2000). Ana Manuku: a prehistoric ritualistic site on Mangaia, Cook Islands. Antiquity, 74(286), 873-883. http://goo.gl/ZySytn |
Thu, 11 August 2016
How Alan Turing's Reaction-Diffusion Model Simulates Patterns in Nature Asparagus Pee Survey Results: https://goo.gl/8x7abL ___________________________________________ If you liked this video, we think you might also like this: Reaction Diffusion Simulation (Gray-Scott model) ___________________________________________ Credits (and Twitter handles): Also, special thanks to the following scientists: Image Credits: Subscribe to MinuteEarth on YouTube: http://goo.gl/EpIDGd ___________________________________________ Here are some handy keywords to get your googling started: Reaction-diffusion system: A hypothetical system in which multiple chemical substances diffuse through a defined space at different rates and react with one another, thereby generating a pattern. Turing pattern: A periodic pattern that forms in a space where the initial distribution of ‘activator’ and ‘inhibitor’ is the same. Morphogenesis: The processes during development that give rise to the form or shape of the organism or a structure Alan Turing: Alan Turing was a British mathematician and the father of modern computer science. During World War II, he broke Germany’s Enigma code used to encrypt communications. ____________________ References: Economou, A. D., Ohazama, A., Porntaveetus, T., Sharpe, P. T., Kondo, S., Basson, M. A., … Green, J. B. A. (2012). Periodic stripe formation by a Turing-mechanism operating at growth zones in the mammalian palate. Nature Genetics, 44(3), 348–351. http://doi.org/10.1038/ng.1090 Economou, A. D., & Green, J. B. (2014). Modelling from the experimental developmental biologists viewpoint. Seminars in Cell & Developmental Biology, 35, 58-65. doi:10.1016/j.semcdb.2014.07.006 Green, J. B., & Sharpe, J. (2015). Positional information and reaction-diffusion: Two big ideas in developmental biology combine.Development, 142(7), 1203-1211. doi:10.1242/dev.114991 Kimura, Y. T. (2016, May 24). The mathematics of patterns. Retrieved from http://www.theshapeofmath.com/princeton/dynsys Kimura, Y. T. (2014). The Mathematics of Patterns: The modeling and analysis of reaction-diffusion equations (Thesis, Princeton University). Http://www.pacm.princeton.edu/documents/Kimura.pdf. Kondo, S., & Asai, R. (1995). A reaction-diffusion wave on the skin of the marine angelfish Pomacanthus. Nature, 376(6543), 765-768. doi:10.1038/376765a0 Kondo, S., & Miura, T. (2010). Reaction-Diffusion Model as a Framework for Understanding Biological Pattern Formation. Science, 329(5999), 1616-1620. doi:10.1126/science.1179047 Marcon, L., & Sharpe, J. (2012). Turing patterns in development: What about the horse part? Current Opinion in Genetics & Development, 22(6), 578-584. doi:10.1016/j.gde.2012.11.013 Raspopovic, J., Marcon, L., Russo, L., & Sharpe, J. (2014). Digit patterning is controlled by a Bmp-Sox9-Wnt Turing network modulated by morphogen gradients. Science, 345(6196), 566-570. doi:10.1126/science.1252960 Stewart, I. (2012). The mathematics of life. Philadelphia, PA: Basic Books. (https://goo.gl/IOagrs) Turing, A. M. (1952). The Chemical Basis of Morphogenesis. Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences, 237(641), 37-72. Retrieved from http://www.dna.caltech.edu/courses/cs191/paperscs191/turing.pdf
Direct download: ME_91_-_Can_Math_Explain_How_Animals_Get_Their_Patterns.mp4
Category:general -- posted at: 12:00pm EDT |