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From the following article: The velocity of climate change Scott R. Loarie, Philip B. Duffy, Healy Hamilton, Gregory P. Asner, Christopher B. Field & David D. Ackerly Nature 462, 1052-1055(24 December 2009) doi:10.1038/nature08649

This case study uses a jigsaw activity to introduce students to four specific plant responses to climate change: elevational range shifts, phenology shifts, community shifts, and changes in biodiversity. Students become "experts" on one of these responses by reading an article (from Nature, Science, or American Journal of Botany; not included with the case) on their assigned topic and then sharing their expertise with others in class. In order to hone their understanding and increase retention on these topics, students then learn about plant communities found in a specific system-vernal pools or seasonal wetlands typical of Mediterranean climates (a PowerPoint presentation on this topic is included). Students accomplish several small group tasks to assess how different vernal pool plant communities have responded to fluctuations in annual weather patterns and predict how these communities may respond to greater weather variability resulting from future climatic change. This case was written for mid- to upper-level ecology, plant ecology, botany, or environmental studies courses. The material covered may also be suitable for classes examining the role of weather variability/climate change in relation to plants.

The agricultural revolution was one of the most profound events in human history, leading to the rise of modern civilization. Now, in the first study of its kind, an international team of scientists has found that after agriculture arrived in Europe 8,500 years ago, people's DNA underwent widespread changes, altering their height, digestion, immune system and skin color. Researchers had found indirect clues of some of these alterations by studying the genomes of living Europeans. But the new study, they said, makes it possible to see the changes as they occurred over thousands of years.

Almost every cell in your body has the same DNA sequence. So how come a heart cell is different from a brain cell? Cells use their DNA code in different ways, depending on their jobs. Just like orchestras can perform one piece of music in many different ways. A cell's combined set of changes in gene expression is called its epigenome. This week Nature publishes a slew of new data on the epigenomic landscape in lots of different cells. Learn how epigenomics works in this video. Read the latest research on epigenetics at http://www.nature.com/epigenomeroadmap

This interrupted case study examines basic concepts of chemical bonding by telling the story of "Madison," a young girl eager to learn how her hair can transition from natural curls to straight, smooth tresses. The case can be used to teach or review the major categories of bonds (ionic, covalent and hydrogen), major macromolecules of life, and hydrolytic and dehydration reactions. It also explores how chemical relaxers and heat through blow drying and flat-ironing can change the nature of straight, wavy and curly hair through the disruption of protein shape. Students will thus learn what it means when a protein has become denatured and how various variables such as pH, heat and salts can lead to the unraveling of the three-dimensional shape of proteins. This case is suitable for an AP high school course, or for an introductory biology or chemistry course for majors or non-majors. This activity can also be used as a review of basic biology and chemistry for students in an upper-level biochemistry course.

In their study of the medium ground finches, evolutionary biologists Peter and Rosemary Grant were able to track the evolution of beak size twice in an amazingly short period of time due to two major droughts that occurred in the 1970s and 1980s. This activity simulates the food availability during these droughts and demonstrates how rapidly natural selection can act when the environment changes. Students use two different types of tools to represent different beak types to see which is best adapted to collect and "eat" seeds of different sizes. Students collect and analyze data and draw conclusions about traits that offer a selective advantage under different environmental conditions. They have the option of using an Excel spreadsheet to calculate different descriptive statistics and interpret graphs.

SciGuides are a collection of thematically aligned lesson plans, simulations, and web-based resources for teachers to use with their students centered on standards-aligned science concepts. Human modifications to communities of living organisms in an ecosystem can change the function and processes of that system. The flow of energy through an ecosystem depends upon the diversity of organisms within it; therefore, when this flow is altered, substantial biological and geological changes occur. It is important that our students not only realize that when a local ecosystem is destroyed or negatively affected by human transformations (building, agriculture, technology); the effect is eventually felt globally. We cannot ignore the fact that everything we do impacts our natural environment. The main question is, "How can we be better "keepers of the Earth"?

The online textbook provides a background to understand and discuss the natural functioning of the different Earth systems; it introduces humans as part of the overall ecosystem and explores what is needed to sustain human life; and it looks at the effects that human actions have on different natural systems. The online textbook also includes full-color images of related figures, glossary terms, and a bibliography for further reading.

Almost every cell in the human body has the same DNA sequence. So why is a heart cell different from a brain cell? Cells use their DNA code in different ways, depending on their jobs - just as the orchestra in this video can perform one piece of music in many different ways. The combination of changes in gene expression in a cell is called its epigenome.

This case is an account of the events that led Drs. Robin Warren and Barry Marshall to the bacterial theory of ulcers. The two physicians refused to accept the standard explanations for what they had observed and instead developed an alternative hypothesis, saving countless patients from unnecessary pain and suffering. Along the way they transformed the way the medical community viewed peptic ulcer disease. The case shows the importance of curiosity, serendipity, and tenacity in scientific inquiry; how science is built upon the work of others; how assumptions can cloud people's views, leaving them closed to new ideas; and how scientific "truth" can and does change when faced with new data and new interpretations. It is appropriate for use in any course at the high school or undergraduate level that teaches students about the scientific method and/or the sociology, nature, and history of science.

Almost every cell in the human body has the same DNA sequence. So why is a heart cell different from a brain cell? Cells use their DNA code in different ways, depending on their jobs - just as the orchestra in this video can perform one piece of music in many different ways. The combination of changes in gene expression in a cell is called its epigenome

" White tigers today are only seen in zoos, but they belong in nature, say researchers reporting new evidence about what makes those tigers white. Their spectacular white coats are produced by a single change in a known pigment gene, according to the study, appearing on May 23 in Current Biology, a Cell Press publication."

The external environment's effects upon genes can influence disease, and some of these effects can be inherited in humans. Studies investigating how environmental factors impact the genetics of an individual's offspring are difficult to design. However, in certain parts of the world in which social systems are highly centralized, environmental information that might have influenced families can be obtained. For example, Swedish scientists recently conducted investigations examining whether nutrition affected the death rate associated with cardiovascular disease and diabetes and whether these effects were passed from parents to their children and grandchildren (Kaati et al., 2002). These researchers estimated how much access individuals had to food by examining records of annual harvests and food prices in Sweden across three generations of families, starting as far back as the 1890s. These researchers found that if a father did not have enough food available to him during a critical period in his development just before puberty, his sons were less likely to die from cardiovascular disease. Remarkably, death related to diabetes increased for children if food was plentiful during this critical period for the paternal grandfather, but it decreased when excess food was available to the father. These findings suggest that diet can cause changes to genes that are passed down though generations by the males in a family, and that these alterations can affect susceptibility to certain diseases. But what are these changes, and how are they remembered? The answers to questions such as these lie in the concept of epigenetics.

n Wednesday, it happened again. Yohannes Haile-Selassie of the Cleveland Museum of Natural History and his colleagues reported finding a jaw in Ethiopia that belonged to an ancient human relative that lived some time between 3.3 and 3.5 million years. They argue that the jaw belongs to an entirely new species, which they dubbed Australopithecus deyiremeda.

"Biologists and informaticists at Indiana University have produced one of the most extensive pictures ever of mutation processes in the DNA sequence of an organism, elucidating important new evolutionary information about the molecular nature of mutations and how fast those heritable changes occur."

Across the globe, as economies grow, so too does the incidence of colorectal cancer. Lifestyle changes are to blame, and in this Nature Video we see how increases in colorectal cancer are affecting many countries around the world, and what this could mean in the future to a world that is still developing.

"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.

This clicker case addresses several important concepts related to evolution. First, it explores artificial selection and selective breeding. Charles Darwin used artificial selection as an example to support his Theory of Evolution by Natural Selection. Belyaev's Fox-Farm experiment is used as an example of a study that used selective breeding as the primary experimental procedure to investigate changes in a lineage. Second, it addresses an interesting observation made by Charles Darwin in The Origin of Species in which he noted how domesticated species also show interesting traits such as drooping ears which seem to be common in domesticated species. The "Farm-Fox Experiment" not only demonstrates how a research team can thoroughly investigate an intriguing question, but also serves as a classic example of elegant experimental design. Designed for use in a large introductory-level biology class, this case study would also be appropriate for smaller classes as well as for upper-level evolution courses.

Nitrogen is one of the primary nutrients critical for the survival of all living organisms. Although nitrogen is very abundant in the atmosphere, it is largely inaccessible in this form to most organisms. This article explores how nitrogen becomes available to organisms and what changes in nitrogen levels as a result of human activity means to local and global ecosystems.

Cancer cells are hungry. To feed their rapid growth and division, their metabolism changes. Moreover, they use sugar (glucose) in a different way to normal cells. This animation, created by Nature Reviews Drug Discovery, explores the key aspects of the altered metabolism in cancer cells and explains how these can be exploited for the development of new anticancer strategies.