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Natural Selection and Adaptation

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The mutation that helped ancient humans survive frostbite probably gave us arthritis. When humans began their slow migration out of Africa some 100,000 years ago, they carried with them the genetic seeds necessary to help survive the bitter chill of Europe and Asia. But, unknowingly, in the same genes lurked a painful burden that afflicts millions today – with a new study finding that a gene variant that helped our ancestors survive extreme climates and frostbite also increases the likelihood of developing arthritis. According to researchers at Stanford and Harvard universities, a variant of the GDF5 gene – which is associated with bone growth and joint formation – has two effects on those that carry mutations of the gene: it reduces bone length (and, subsequently, height), and it can almost double the chance of osteoarthritis.

"It's clear that the genetic machinery around a gene can have a dramatic impact on how it works," says one of the researchers, human evolutionary biologist Terence Capellini, now at Harvard University. The findings are reported in Nature Genetics. Case Study: How Did the Guppy Get His Color? This case study examines evolution in guppies as evidenced by color variation in populations.

It is based on an iconic study performed by John Endler where he collected data on guppies by scoring the size, number, and brightness of spots. Students progress though the slides (lecture and discussion), and examine details of Endler’s study, such as where the pools were located and why natural barriers created different environments for the native guppies. The case also examine two predatory fish found in Trinidad, the killifish (Rivulus hartii) and the pike (Crenichichla alta).

Students then examine real data gathered in the experiment that showed how the color and number of spots found on guppies was related to the types of predators in the stream. Students should be able to conclude that in streams with aggressive predators, natural selection favors guppies that do not have bright spots. Students can also explore a NetLogo simulation on guppies and predators.

Earth - Chicken grows face of dinosaur. Sixty-five million years ago, an asteroid is believed to have crashed into Earth. The impact wiped out huge numbers of species, including almost all of the dinosaurs. One group of dinosaurs managed to survive the disaster. Today, we know them as birds. The idea that birds evolved from dinosaurs has been around since the 19th century, when scientists discovered the fossil of an early bird called Archaeopteryx.

It had wings and feathers, but it also looked a lot like a dinosaur. But these early birds didn't look the same as modern ones. To understand how one changed into another, a team has been tampering with the molecular processes that make up a beak in chickens. By doing so, they have managed to create a chicken embryo with a dinosaur-like snout and palate, similar to that of small feathered dinosaurs like Velociraptor. The team's aim was to understand how the bird beak evolved, because the beak is such a vital part of bird anatomy. "These weren't drastic modifications," says Bhullar. Online Learning. What did T. rex taste like? Evolution – what next? Phylogenetic Predictions | Tree of Life : Exhibits : Yale Peabody Museum of Natural History. Phylogenetic trees predict the characteristics of species that have not yet been carefully studied.

This can guide the search for useful natural products, including “bioprospecting” for new drugs. For example, the drug “taxol,” which is used to treat breast cancer, was first isolated from the Pacific yew plant. A focus on related plants turned up a similar chemical in a more widespread species, which greatly enabled the production of the drug. Treating Snake Bites In Australia, which has more poisonous snakes than any other continent, phylogenetic analysis is used to help identify antivenins. The “Poison” in Poison Ivy Some people who are sensitive to poison ivy discover that they have a similar reaction to the skin of mango fruits. They both belong to the Cashew family, the Anacardiaceae.

And what about the cashew itself? Another plant that belongs to the Anacardiaceae is the Japanese lacquer tree, which is used to make exquisite traditional lacquerware. TimeTree :: The Timescale of Life. Teaching Resources | J.F. Crow Institute for the Study of Evolution. Goldsmith Clade Race. Evolution | NOVA Labs. Evolution of Early Predators | the Shape of Life | The Story of the Animal Kingdom. Let’s All Do The Wave! | the Shape of Life | The Story of the Animal Kingdom. Nature's Innovations: Animals as Engineers | the Shape of Life | The Story of the Animal Kingdom. Lesson: evolution mini-lesson: A Step in Speciation. Time: Two 50-minute periods Preparation: 1. Make color copies of the salamander sheets (one per team of 2-4); place these in non-glare transparent plastic notebook sleeves to protect from wear and tear as they are re-used every period and year. 2.

Make copies of Grid Map of California. Enlarged copies would work best (one per team). 3. 4. 5. 6. 7. COMMENT: This lesson demonstrates how speciation occurs and should emphasize for students that a scientist's real work begins when she/he starts to organize and analyze data. PRESENTATION: 1. 2. 3. 4. 5. 6. RECENT DEVLOPMENTS AND CURRENT STUDIES OF ENSATINA at ENSATINA UPDATE: Confirmation of hypothesized relationship from DNA analyses and other studies (added February, 2010).

When Predators Attack

All 2.3 Million Species Are Mapped into a Single Circle of Life. Since Charles Darwin's day, biologists have depicted how new organisms evolve from old ones by adding branches to numerous trees that represent portions of the animal, plant and microbial kingdoms. Researchers from a dozen institutions recently completed a three-year effort to combine tens of thousands of trees into one diagram, most readable as a circle (below). The lines inside the circle represent all 2.3 million species that have been named. Biologists have genetic sequences for only about 5 percent of them, however; as more are finished, the relationships within and across groups of species may change. Experts estimate that up to 8.7 million species may inhabit the planet (about 15,000 are discovered every year). “We expect the circle to broaden,” says Karen Cranston, a computational evolutionary biologist at Duke University. Anyone can propose updates to the database (OpenTreeOfLife.org). Click or tap to enlarge.

Selection for Tuskless Elephants. The Origin of Species: The Beak of the Finch. Sorting Finch Species. Natural Selection and the Evolution of Darwin's Finches. Evolution in Action: Data Analysis. Beaks As Tools: Selective Advantage in Changing Environments. Evolution Evidence EvolutionEvidence.org: A New Method for Teaching Evolution Evidence.

Smilodon Reading and Questions

1120L Adaptation. 1090L Naturally Selected to Survive. ENSI/SENSI Lesson List: Evolution. Genetic Science Learning Center. Launch Tool The Genetic Science Learning Center is a great place to visit to explore and learn about cells, heredity, DNA, genes, natural selection, etc. The Learn.Genetics part of the site is geared to students, teachers, and the general public.

It delivers educational materials on genetics, bioscience, and health topics. The homepage is divided into three main sections: Basics, New & Popular, and a section that highlights a variety of topics, from genetic technology to the new science of addiction. The site uses videos, animations, and interactives to help you explore the different topics. Going Further For Educators In addition to the Learn.Genetics part of the site, you can make use of the Teach.Genetics section, which has resources and information aimed at helping you bring genetics, bioscience, and health alive in the classroom. Teach.Genetics also provides unit plans and other supporting resources, such as talks by scientists with expertise in genetics. Genes and Geography. Photo Credit: NASA Our early human ancestors began migrating across the globe tens of thousands of years ago. Some left behind archaeological evidence of their travels.

But as you'll hear in this Science Update, another record of where we come from and where we've been might be found right in our DNA. Transcript Genes and geography. People around the world might look different from one another, but inside, we're pretty similar—and that's true even of our genes. Noah Rosenberg is a research associate at the University of Southern California. Rosenberg: One thing we found was that the amount of variation across populations was smaller than we had originally expected and smaller than had been found previously.

Nevertheless, those sites could be used to predict that person's ancestry solely based on their DNA. Rosenberg: This is helpful towards trying to figure out the relationships between different populations and the patterns of human migration. Making Sense of the Research. NGSS Bio LS 2-8 Grouping. Rare Dinosaur-Era Bird Wings Found Trapped in Amber. Two tiny wings entombed in amber reveal that plumage (the layering, patterning, coloring, and arrangement of feathers) seen in birds today already existed in at least some of their predecessors nearly a hundred million years ago. A study of the mummified wings, published in the June 28 issue of Nature Communications and funded in part by the National Geographic Society's Expeditions Council, indicated they most likely belonged to enantiornithes , a group of avian dinosaurs that became extinct at the end of the Cretaceous period. (Read more about the evolution from dinosaurs to modern birds.) 'Mind-Blowingly Cool' While the fact that many, if not nearly all, dinosaurs were feathered has been generally accepted since the 1990s, our knowledge of prehistoric plumage until now has come from feather imprints in carbonized compression fossils and individual feathers fossilized in amber.

(See dinosaurs in their feathered glory.) Familiar Feathers A Bountiful Fossil Source in a Troubled Area. Classroom Activities: Biodiversity and Evolutionary Trees. Sandwalk: The Adaptation Assessment Probe. I'm taking a MOOC on evolution that's designed for educators [Evolution: A Course for Educators]. One of the things that was covered in the first lecture was a test on "adpatation" taken from a book called "Uncovering Student Ideas in Science, Volume 4: 25 New Formative Assessment Probes. The book is published by the National Science Teachers Association (NSTA). Let's take the test ... Adaptation Three friends were arguing about what would happen if a population of rabbits from a warm, southern climate were moved to a cold, northern climate.1 This is what they said:Bernie: "I think all of the rabbits will try to adapt to the change.

"Leo: "I think most of the rabbits will try to adapt to the change. " I agree with Bernie. Let's see how I did. Oops! The best answer is Phoebe's: "I think few or none of the rabbits will try to adapt to the change. " I didn't read the question carefully. We turned our clocks back one hour last weekend and I'm still adapting adjusting to the change. 1. Is%20It%20Fitter. Habitat%20Change. Origami Birds. Darwin Finches. ENSI/SENSI: Evolution/Nat.of Sci.Home Page. 19 February 2017 ATTENTION, FILMMAKERS! A chance to make a film about evolution and win a prize! Scientists and science educators of all stripes -- students, postdocs, faculty, and full- or part-time science communicators -- are invited to enter the Seventh Annual Evolution Video Competition, sponsored by the Duke Initiative for Science & Society, the Howard Hughes Medical Institute, the Society for the Study of Evolution, and the BEACON Center for the Study of Evolution in Action.

To enter, please submit a video that explains a fun fact, key concept, compelling question, or exciting area of evolution research in three minutes or less. Entries may be related or unrelated to your own research, and should be suitable for use in a classroom. Videos should be both informative and entertaining. The finalists will be screened at the Evolution 2017 meeting in Portland, Oregon. For information about the contest, visit: Evolution. Caught in the act. Most animals, plants and other organisms possess a broad range of traits, or features. For instance, within a species, some individuals might be bigger. Some might be faster or better camouflaged. Others might have genes that allow them to resist disease, better digest some foods or even learn new tasks more quickly.

Many traits help an organism survive and reproduce. These traits often can be inherited. That means an organism can pass them down to its offspring. Once-useful traits, however, can become worthless. Until recently, scientists thought such evolution required hundreds of years, if not thousands. These major transformations to our planet still happen. People also change Earth’s air, water and land. Such environmental changes pressure species to adapt ever faster. Shape-shifters When it comes to survival, animals have two immediate concerns. Van Rijssel is an evolutionary ecologist at Leiden University in the Netherlands. Courtesy of Jacco van Rijssel Silent night Others are not. Charles Darwin’s Game of Survival.

TimeTree :: The Timescale of Life. Evolution in Paradise. We are pleased to bring you three exciting lessons inspired by the birds-of-paradise! These lessons explore the topics of science process, natural and sexual selection, behavior and heritability through hands-on activities and lively discussions… all with the help of the Birds-of Paradise Project videos. This free download is perfect for middle and high school classrooms. Read more about this exciting resource or simply click the button to download. Later, be sure to visit our resources page to find helpful links and additional background information and resources. Scientists Watch As Wasps Diverge To Become Separate Species. We often think of evolution as something which occurs slowly over millions of years, only being recorded in the fossils that are left behind. But evolution is gradual, with species constantly changing in response to a host of different pressures, from alterations in their environment to changes in other species they reply on.

This last point, of species evolving and splitting in response to other species evolving and splitting, is a central concept in biodiversity, but is also a difficult one to prove. A new study has, however, apparently done just this. Researchers from Rice University have documented how as one species of fruit fly is evolving into two separate species that exploit different food, three species of wasp, which parasitize the fruit fly, are also splitting into six new species.

This proves how as habitats become more complex, with increasing numbers of species present, it forms a feedback loop that in turn causes yet more species to evolve.

Animal Behavior

More Minds-on Activities for Teaching Biology. The resources listed below include: minds-on, hands-on activities and minds-on analysis and discussion activities for teaching biology to high school and middle school students and students in non-major college biology coursesoverviews of important biological topicsgames for learning and review. Many of these activities are explicitly aligned with the Next Generation Science Standards, as indicated by (NGSS) in the descriptions below and as described in Summary Tables and in the Teacher Notes for individual activities.

These activities foster student understanding of Disciplinary Core Ideas, engage students in Scientific Practices, provide the opportunity to discuss Crosscutting Concepts, and prepare students to meet the Performance Expectations of the Next Generation Science Standards. We encourage you to subscribe to our listserv to receive notices when we post new activities or significantly improved versions of current activities. Intro and Biological Molecules Is Yeast Alive? Origami Birds. Darwin Finches.

Cladistics

It Takes Teamwork: How Endosymbiosis Changed Life on Earth. Teaching_strategies. AIDS: Evolution of an Epidemic. Evolution: Constant Change and Common Threads (Available for Check-out) Cosmos A Space Time Odyssey - Some of the Things That Molecules Do Season 1 Full Episode 2. Great fossil find. Paused: Oops. Genghis Khan. Microsoft Word - Breeding Bunnies.doc - Breeding Bunnies.pdf. Timeline Eons FREE. Charles Darwin's Game of Survival.

U1_L7_LessonPlan.pdf. U1_L6_LessonPlan.pdf. Evolution: Library: Threat of Tuberculosis. Inheritance. SurvivaloftheSneakiest. Origami Birds. Evolution: Change: All in the Family. Natural Selection - Natural Selection, Evolution, Mutation. ENSI/SENSI Lesson List: Evolution. Short Films. NIH Curriculum Supplement Series for High School - Evolution and Medicine. TimeTree :: The Timescale of Life. Main. Cut and Run. Ss0707_24. BIO_Quackers and Cottontails_web.indb - BIO_Quackers and Cottontails_web.pdf. Evolution. 100 Years of Breed “Improvement” | Science of Dogs. Holiday Lectures on Science. Charles Darwin's Game of Survival. Virtual Age Dating portal. Explorations Through Time. Click and Learn. Biological Evolution. Spork & Beans: Addressing Evolutionary Misconceptions. ENSI/SENSI Lesson List: Evolution.

Evolution: Online Lessons for Students: Activity 4- Activity Title. Becoming Human. Human Evolution by The Smithsonian Institution's Human Origins Program. BioInteractive Search Results. BioInteractive Search Results. Bird Beak Adaptations - Natural Selection (Diana Van Pelt) - sed555f11. Understanding Evolution.

Clipbirds. Lots of lessons.

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