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Mathematician-turned biologist Dr. Corina Tarnita describes the importance of termite mounds in a savanna ecosystem. Termite mounds are biological hotspots that concentrate nutrients and water in semi-arid savanna ecosystems. When viewed from above, the mounds form a strikingly regular polka-dot pattern. Dr. Corina Tarnita uses mathematical modeling to explain the regularity of the pattern, how it arises, and how the mounds enhance the stability of the ecosystem.

Focusing on this species of fruit fly, he and the other researchers in the lab of molecular biologist Sean B. Carroll, had made a prolonged assault on one of the key questions in evolutionary biology: how nature endows creatures with their colorful patterns, from a leopard's dark spots to a butterfly's bold swirls. In different species the patterns serve to attract mates, provide camouflage or provide other advantages in the struggle to survive. But what causes the colors to fall so precisely into place?

"We have found that the best way to keep a record of activity and ideas is to create a table with four columns-1) Activities we did, 2) Patterns or observations, what happened?, 3) What do you think caused these patterns or observations?, 4) How do these patterns help us think about the essential question or puzzling phenomenon? "

Activity A Better Fire!! Activity Advanced Fire Activity Directable Fire!! Activity Fire!! Activity Life Activity Life Lite Activity Spread of Disease Discussion about Agent Modeling Discussion about Chaos Discussion about Chaos is Everywhere Worksheet Emerging Patterns Worksheet Worksheet Emerging Patterns Worksheet (doc) Worksheet Rabbits and Wolves Exploration Questions Worksheet Rabbits and Wolves Exploration Questions (doc)  

When it's completely unraveled, DNA is known to extend approximately six feet in length, yet is somehow able to cram itself into a cell's nucleus. In a study published today (July 27) in Science, researchers created a novel visualization method that revealed a 3-D glimpse of chromatin as it sits jam-packed within the nuclei of human cells. The researchers found that, contrary to how it's depicted in most textbooks, chromatin does not fold in on itself in an organized manner to create distinct structures. Instead, it forms a pliable, inconsistent chain characterized by a wide variety of folding patterns. 

This interrupted case study for the flipped classroom applies evolutionary genetics research to human health. Students learn about a naturally occurring, but rare, allele of the CCR5 gene, CCR5-Δ32, which provides resistance to HIV. They use data from primary literature sources to predict and interpret worldwide patterns of CCR5-Δ32 frequency distribution. They then discuss how these allele frequency patterns may have been driven by selection imposed by various diseases or by other evolutionary mechanisms. Next, they test published data using Hardy-Weinberg equilibrium to examine if CCR5-Δ32 also provides genetic resistance to West Nile virus. Finally, they complete a jigsaw discussion of Nature News articles that report on how CCR5 research is being used to develop therapies to treat HIV. Originally written for the evolution portion of a yearlong biology series for undergraduate majors, the case is also appropriate for some non-majors biology courses or, with added complexity, upper-level evolution, genetics, or cell biology courses.

This interrupted case study examines molecular genetic evidence reported in scientific literature to determine the fate of Louis-Charles, son of Louis XVI and Marie-Antoinette of France. Controversy and rumors surrounding the death of Louis-Charles suggested that either he died as a young boy while being held in captivity by the French revolutionaries or he escaped and was replaced by a substitute who died in his place. One individual claiming to be Louis-Charles was Karl Naundorff. Students begin the case by preparing pedigrees for the descendants of Maria Theresa and Francis I, the Holy Roman Emperor, parents of Marie-Antoinette. The pedigrees can be used to introduce the concepts of alleles identical-by-descent and cytoplasmic inheritance patterns. Students then compare mitochondrial DNA sequences and XY chromosome sequences from hair, bone, heart, and blood samples taken from descendants of Marie Theresa, Karl Naundorff and the heart of the boy who died in captivity to determine if the latter was truly Louis-Charles. An optional PowerPoint presentation with clicker questions is available to help guide the classroom activities.

That's why the annual County Health Rankings are important. They not only show health standards at a local level-they also show the multiple factors that pertain to health outcomes, everything from racial segregation and sleep patterns to smoking rates and access to decent food.

269 page  Curriculum Supplement from NIH 5 lessons  Ideas about the role of evolution in medicine Investigating lactose intolerance and evolution evolutionary processes and patterns inform medicine Using evolution to understand influenza Evaluating evolutionary explanations

Researchers analysed the genomes of 51 individuals who lived between 45,000 years ago and 7,000 years ago. The results reveal details about the biology of these early inhabitants, such as skin and eye colour, and how different populations were related. It also shows that Neanderthal ancestry in Europeans has been shrinking over time, perhaps due to natural selection. The study in Nature journal shines a torchlight over some 40,000 years of prehistory, showing that ancient patterns of migration were just as complex as those in more recent times.

A stride to understand the cancer and move towards its prevention, this time experts from around the world involved in searching the genome of cancer have analyzed the mutational signatures, the processes of mutation in the DNA of cells (which are always in the origin of cancer) and they follow a fixed pattern.

activities

In essence, the young people's bodies seemed to be somehow remembering and responding to what that body had just been doing, whether sitting or moving, and then calculating a new, appropriate response - moving or sitting. In doing so, the researchers felt, the body created a healthy, dynamic circadian pattern.

The activity of some of our genes varies with the seasons throughout the year. The discovery comes from an analysis of blood samples from more than 16,000 people in both hemispheres. The most striking pattern was that 147 genes involved in the immune system made it more reactive or "pro-inflammatory" during winter or rainy seasons, probably to battle the onslaught of cold and flu viruses

There are a significant number of genetics curriculum resources designed by different companies, curriculum development outlets, state curriculum designers and individual teachers. What resources are good? How do you know? As part of the Geneticist-Educator Network of Alliances (GENA) Project, a Curriculum Content Review Committee was formed to review readily available classroom resources about patterns of inheritance. Click here to see original evaluation form used by the committee and here to see the summary of the committee's review.

When you leave the house, does your dog or cat even remember you? Read More: A Rat's Tenacious Memory http://www.indiana.edu/~rcapub/v17n1/... "In the wild, rats scramble over the network of pathways they have created, combing their surroundings for food, water, mates, and shelter. Their movements may seem automatic to the untrained eye, simply a reflexive pattern. Decades ago, however, researchers established that rats know where they are going and remember where they have been."

"Survival of the Fittest: Variations in the Clam Species Clamys sweetus" is a guided inquiry. This series of hands-on activities complements the HHMI DVD Evolution: Constant Change and Common Threads and requires simple materials such as M&Ms, Reese's Pieces, food storage bags, and paper cups. This activity has been designed to engage students in thinking about the mechanism of natural selection by encouraging them to formulate questions that can be answered through scientific investigation, data collection, and pattern recognition.

Life sciences focus on all things living, exploring the patterns, processes and relationships of organisms. The goal of life sciences is to demonstrate how unifying principles can help us to make sense of the natural world and solve problems in the world we live in. High school life sciences extend student knowledge of topics such as organisms, ecosystems, heredity and evolution, integrating a long history of scientific research from multiple fields. In high school, students will build on their conceptual understanding of life sciences by investigating and witnessing the relationships among structure and function, matter and energy, ecosystems and natural selection. Students should be able to effectively communicate facts and findings, as supported in the science literacy skills covered in the Common Core State Standards.

A new study by Duke University researchers helps clarify the matter by showing how a sugar habit changes specific brain circuits, and how those changes produce cravings that reinforce the habit. The research team began by getting a group of healthy mice hooked on sugar. Similar to classic studies on drug addiction, the mice in this study were trained to press a tiny lever to receive doses of sweets. Once the mice were hooked, they continued pressing the lever even when the sweets were removed. So that was step one, establishing a behavioral pattern to get the goods.

The Y chromosome is only one-third the size of the X. Although the Y has a partner in X, only the tips of these chromosomes are able to recombine. Thus, most of the Y chromosome is inherited from father to son in a pattern resembling asexual, not sexual, reproduction. No recombination means no reassortment, so deleterious mutations have no opportunity to be independently selected against. The Y chromosome therefore tends to accumulate changes and deletions faster than the X. Degradation doesn't occur in X chromosomes because during female meiosis, the X has the other X as a full partner in recombination.