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Natural selection

Natural selection
Related:  Year 10 Evolution

From prokaryotes to eukaryotes From prokaryotes to eukaryotes The complex eukaryotic cell ushered in a whole new era for life on Earth, because these cells evolved into multicellular organisms. But how did the eukaryotic cell itself evolve? How did a humble bacterium make this evolutionary leap from a simple prokaryotic cell to a more complex eukaryotic cell? The answer seems to be symbiosis — in other words, teamwork. Evidence supports the idea that eukaryotic cells are actually the descendents of separate prokaryotic cells that joined together in a symbiotic union.

Complicity and the Brain: Dynamics in Attractor Space Dr. Peter Henningsen Abstract: This paper outlines a research program that is intended to look for the emergence of consciousness in computers. We argue that a good place to look is the space of Self-Organizing Networks of Attractor Neural Networks (SONofANNs). In the main part of the paper, we then specialize our investigation to Self-Organizing Hopfield Networks (SOHNs), and construct a model that can give rise to emergent semantic networks and brainwave processing, two new concepts introduced here. This paper is structured in five parts: Parts 1 and 2 introduce a class of dynamic systems called SONkANNs - self-organizing networks (k times iterated) of attractor neural networks. Decomposing the Neocortex into Subsystems When analyzing a complex system, the first step is to check whether the system can sensibly be decomposed into subsystems. There are other reasons as well. Possible Subsystem Dynamics Levels of Emergence in the Brain Creating Complicity from Scratch

guppy Name:_________________________________________ The purpose of this activity is to analyze how guppy populations change over time. The simulation activity allows you to start with a pool of guppies and your choice of predators, you will be able to watch what happens to your guppy population and how the introduction of predators can affect the guppy's appearance. *Activity adapted from PBS - Open the Guppy Sex Simulator!! Introduction: 1. 2. 3. 4. Endler’s Discovery and Variations of Guppy’s in Pools 5. 6. Pool 1:Pool 2:Pool 3: 7. Guppy Simulation 8. 9. 10. 11. 12. 13.

Evolution via Roadkill Cliff swallows that build nests that dangle precariously from highway overpasses have a lower chance of becoming roadkill than in years past thanks to a shorter wingspan that lets them dodge oncoming traffic. That's the conclusion of a new study based on 3 decades of data collected on one population of the birds. The results suggest that shorter wingspan has been selected for over this time period because of the evolutionary pressure put on the population by cars. "This is a clear example of how you can observe natural selection over short time periods," says ecologist Charles Brown of the University of Tulsa in Oklahoma, who conducted the new study with wife Mary Bomberger Brown, an ornithologist at the University of Nebraska, Lincoln. The Browns have studied cliff swallows (Petrochelidon pyrrhonota) in southwestern Nebraska since 1982. The birds that were being killed, further analysis revealed, weren't representative of the rest of the population.

Peppered Moth Simulation Name:______________________________________________ Objective: Simulate changes in moth population due to pollution and predation, and observe how species can change over time. Introduction: Charles Darwin accumulated a tremendous collection of facts to support the theory of evolution by natural selection. The economic changes known as the industrial revolution began in the middle of the eighteenth century. Instructions: Click the link below to read more information on Kettlewell's study of moths. After 5 minutes record the % of dark moths and light moths - you will need this information later. Peppered Moth Simulation at Data and Analysis Read the background information and answer the questions as you go. Life Cycle of the Peppered Moth 1. 2. 3. 4. 5. 6. Impact of Pollution 7. 8. 9. 10. 11. 12. Kettlewell's Experiments 13. 14. 15. 16. 17. 18. 19. 20. Birdseye View 21. Final Analysis 22. 23. 24. – online reading for free. guppy The purpose of this activity is to analyze how guppy populations change over time. The simulation activity allows you to start with a pool of guppies and your choice of predators, you will be able to watch what happens to your guppy population and how the introduction of predators can affect the guppy's appearance. The simulation will help you understand what pressures drive guppy evolution. *Activity adapted from PBS - Open the Guppy Sex Simulator!!! Introduction First of all, familiarize yourself with the site, you should know each of the following before proceeding to the simulation. View the guppy gallery, know the color variations found among guppies View the predator gallery, know the types of predators of guppies Read about John Endler's experiment View the three types of pools and know what guppy colors are common in each area Read the three possible hypotheses for guppy coloration Experiment 1. 3. The Simulation Grading

Defender's Guide to Science and Creationism Introduction Share Not for over a century has there been any scientific controversy over creationism. Assertions Analyzed Bracketed dates indicate a new entry. I: Cosmology and astronomy Objections to Big Bang theory Objections to natural astronomical processes Astronomical objections to the old age of the universe and its contents Miscellaneous The fine-tuning of the cosmological constants proves the universe was created. II: Geology and the age of the earth Objections to radiometric dating Geological objections to the old age of the earth Noah's Flood was caused by the condensation of a vapor canopy which also enabled people to live hundreds of years by screening out UV rays. III: Abiogenesis (the origin of life) General objections to abiogenesis The panspermia hypothesis is useless because it just pushes back the question of how life originated. IV: Evolutionary biology Mutation Speciation Things that supposedly could not have evolved Counterarguments against evidence for evolution V: Paleontology

Before DNA, before RNA: Life in the hodge-podge world - life - 08 January 2012 Take note, DNA and RNA: it's not all about you. Life on Earth may have begun with a splash of TNA – a different kind of genetic material altogether. Because RNA can do many things at once, those studying the origins of life have long thought that it was the first genetic material. But the discovery that a chemical relative called TNA can perform one of RNA's defining functions calls this into question. Instead, the very first forms of life may have used a mix of genetic materials. Today, most life bar some viruses uses DNA to store information, and RNA to execute the instructions encoded by that DNA. A key piece of evidence for this "RNA world" hypothesis is that RNA is a jack of all trades. Now it seems TNA might have been just as capable, although it is not found in nature today. It differs from RNA and DNA in its sugar backbone: TNA uses threose where RNA uses ribose and DNA deoxyribose. The team took a library of TNAs and evolved them in the presence of a protein. No TNA world

Twitter for Mac update When Twitter for Mac launched at the beginning of the year it received praise for its simplicity, speed and look. It also came packed with features like auto-shortened URLs, Tweets appearing in real-time, and multi-account support.Today, we’re releasing the first major update to Twitter for Mac. Some of the highlights: See multiple timelines at once. You can download the update from the Mac App Store now.

Darwin/Lamark court case By Don Mills This six to seven 40 minute period activity allows students to role play while learning theories of evolution. To start this activity have your students write their names on scrap pieces of paper. JUDGE : Preside over court, follow judicial rules and maintain order in court.BAILIFF : Call court to order, introduce judge, and swear in witnesses.COURT REPORTERS (2) : Record all proceedings in a notebook.DARWIN and LAMARCK : Tell where they were educated and what they have done in life. Group 2 : Research how the paleontologist can provide giraffe evidence that supports your person's theory. Group 3 : Research using SIRS and encyclopedias, etc. to find other witnesses. Group 4 : Using the list of witnesses from the other side, which the other side has provided your group, look up possible cross examination questions for each witness provided (you should know the responses you expect.) Trial procedures and hints: Witnesses - you should have notes with you at the stand.

Using Appropriate Terminology Function not purpose The purpose of a hammer is to pound nails. One function of a hand is to hold a hammer. Designed tools have purposes. Evidence not proof We often hear news stories in which the narrator refers to having “enough proof.” Primitive and advanced The average person might see an opossum as more primitive than a cat. Theory vs. hypothesis A theory is an explanation. A hypothesis is a testable idea. Believe or accept “Do you believe in evolution?”