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This case study follows purveyors of peas, Joel E. and Jolene Greengiant, as they learn about the origin, biochemistry, genetics and eventual artificial selection of sweet (wrinkled) peas, all in the context of evolutionary biology. This integrative approach employs both problem-based learning techniques and directed questions as students engage in a series of modules. 

Nature's best kept secret is a wonder molecule called RNA. It is central to the origin of life, evolution, and the cellular machinery that keeps us alive. In this Lab you'll play the role of a molecular engineer by solving RNA folding puzzles. Then take your skills to Eterna, where you can design RNAs that could be at the heart of future life-saving therapies.

4:43 Cancer usually begins with one tumor in a specific area of the body. But if the tumor is not removed, cancer has the ability to spread to nearby organs as well as places far away from the origin, like the brain. How does cancer move to these new areas and why are some organs more likely to get infected than others? Ivan Seah Yu Jun explains the three common routes of metastasis.

virtual lab on deformed amphibians with reference to original research

Earlier this week, the space agency released a new simulation created with this model, called GEOS-5, that shows clouds of carbon dioxide, a key driver of global warming, drifting far from their original sources - turning local greenhouse gases into global problems.

When a person dies from cancer, the culprit is usually not the original tumor but rather the cancerous cells that spread throughout the body and replicate in distant organs, a process called metastasis. Researchers have long known that metastasizing cancer cells slip their bonds and avoid immune detection by altering the sugars on their surfaces. They've even come up with a would-be drug to prevent such sugar alterations. But that compound interferes with needed sugars on normal cells, too, with lethal results in animals. Now, Dutch researchers report that they've packaged the drug in nanoparticles targeted exclusively to cancer cells, and they've shown that this combination prevents cancer cells from metastasizing in mice.  

This groundbreaking NRDC documentary explores the startling phenomenon of ocean acidification, which may soon challenge marine life on a scale not seen for tens of millions of years. The film, featuring Sigourney Weaver, originally aired on Discovery Planet Green.

This groundbreaking NRDC documentary explores the startling phenomenon of ocean acidification, which may soon challenge marine life on a scale not seen for tens of millions of years. The film, featuring Sigourney Weaver, originally aired on Discovery Planet Green.

Shape of Life is a series of short classroom videos that beautifully illustrate the evolution of the animal kingdom on planet earth. Based upon an original PBS Series, Shape of Life, is especially designed for students and teachers who want a first-hand account of how animals adapt and thrive.

The CDC released travel health notices Tuesday that named two more places in which the disease has spread via mosquito bites: The US Virgin Islands and the Dominican Republic.  The Zika virus is primarily transmitted by Aedes aegypti, the type of mosquito responsible for spreading dengue, yellow fever, and a whole host of other tropical infectious diseases. Originally identified in 1947 in Uganda, Zika was relatively unknown until 2007, when there was an outbreak of the virus in Micronesia. The mosquitoes pick up the virus from infected people, according to the CDC. 

A complete understanding of evolution requires knowledge that spans many biological sub-disciplines. However, students are often taught evolution in the context of ecological systems and isolated from genetic and cellular ones. To address this issue, we have developed case studies that track the evolution of traits from their origination in DNA mutation, to the production of different proteins, to the fixation of alternate macroscopic phenotypes in reproductively isolated populations.

This case study presents the story of Phil, an undergraduate majoring in biology, whose Russian cousin Dimitri has contracted tuberculosis (TB) from inmates at the prison where he works.  Phil learns that his cousin's failure to complete his antibiotic regimen likely contributed to the evolution of antibiotic-resistant TB in his body.  Phil consults with his friend Stacy, and together they try to understand Dimitri's condition by applying what they are learning in their genetics lab experiment about the role of random mutation in bacterial evolution (including the development of antibiotic resistance) through Luria- Delbrück fluctuation analysis. The same analysis includes calculation of the mutation rate, which Phil realizes is sufficient to cause MRSA and other antibiotic-resistant infections. This case study was originally developed for concurrent use in freshman/sophomore-level genetics, elementary statistics, and precalculus. However, it is also very appropriate for courses in introductory biology, evolutionary biology, and biostatistics. The teaching notes discuss various ways to run the case depending on the mathematics and biology background of students.

In the closing sentence of "The Origin of Species," Charles Darwin marvels at the process of evolution, observing how "from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved." Few people would describe bedbugs as most beautiful or most wonderful. Yet this blood-feeding pest may represent an exceptional chance to observe the emergence of Darwin's "endless forms": New research indicates that some bedbugs are well on their way to becoming a new species.

And as the El Nino weather system has been storming across the Pacific this season, it has stirred up ocean waters enough to cool down the original Blob off of Alaska, but at the same time helped give birth to what has been nicknamed the "Son of Blob" off the coast of Southern California. The still-warmer Alaskan waters, and Son of Blob sector are expected to continue to magnify the El Nino effect for months to come, according to Weather Underground's "Blob Watch" blog.

The worst cancer cells don't sit still. Instead they metastasize-migrate from their original sites and establish new tumors in other parts of the body. Once a cancer spreads, it is harder to eliminate. A study by developmental biologists offers a fresh clue to how cancer cells acquire the ability to invade other tissues-a prerequisite for metastasis. It reveals that invasion requires cells to stop dividing. Therefore, the two processes- invasion and proliferation-are mutually exclusive. The finding could inform cancer therapies, which typically target rapidly proliferating cancer cells.

Quintana-Murci and his colleagues also took advantage of a previously published map of areas of the human genome where Neanderthal genes are present, showing that innate immune genes are generally more likely to have been borrowed from Neanderthals than genes coding other types of proteins. Specifically, they noted that 126 innate immune genes in present-day Europeans, Asians, or both groups were among the top 5 percent of genes in the genome of each population most likely to have originated in Neanderthals. The cluster of toll-like receptor genes, encoding TLR 1, TLR 6, and TLR 10, both showed signs of having been borrowed from Neanderthals and having picked up adaptive mutations at various points in history. Meanwhile, a group led by Janet Kelso of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, used both the same previously published Neanderthal introgression map that Quintana-Murci used and a second introgression map. The researchers searched for borrowed regions of the genome that were especially long and common in present-day humans, eventually zeroing in TLR6, TLR10, and TLR1. These receptors, which detect conserved microbial proteins such as flagellin, are all encoded along the same segment of DNA on chromosome four.

4:43 video Cancer usually begins with one tumor in a specific area of the body. But if the tumor is not removed, cancer has the ability to spread to nearby organs as well as places far away from the origin, like the brain. How does cancer move to these new areas and why are some organs more likely to get infected than others? Ivan Seah Yu Jun explains the three common routes of metastasis. 

Polar bears are an iconic symbol of climate change, but regionally relevant examples of susceptible biota are needed to highlight how global forces impact local environments. In this interrupted case study, students follow a young naturalist as she explores why saltmarsh sparrows are increasingly rare in coastal wetlands of the northeastern United States. In small groups, students diagram how sea-level rise may alter saltmarsh sparrow habitat and analyze a graph to determine if there is evidence to support sea-level rise. The social implications of rising sea levels induced by climate change can also be explored with an optional jigsaw activity. Students who successfully complete this case study will integrate key concepts related to sea level rise, interpret scientific data and draw conclusions about environmental change, and evaluate alternative management decisions. Originally developed for an undergraduate ecology course, the case could easily be adapted by college or high school instructors for an introductory biology or an environmental science course.

This case study follows two beginning undergraduate researchers on a quest for a summer research project related to food web ecology. While writing their research proposal, the students receive feedback indicating that they have neglected an entire group of organisms from their food web-parasites, which leads them to a scientific research paper discussing how these organisms have been overlooked by scientists studying food webs, the challenges involved with including parasites in food webs, and the contributions parasites ultimately make to food webs. An integrated activity in which students visualize the food web using images of organisms and answer questions about species interactions provides opportunities to examine key concepts such as omnivory, ontogenetic diet changes, trophic levels, complex life cycles, and taxonomic aggregation. This case study was originally written for an undergraduate general ecology course, but could easily be adapted to undergraduate general biology courses covering community ecology or specific courses in invertebrate zoology, parasitology, or disease ecology. The teaching notes also discuss how the included code for R statistical computing software can be used to extend the case study in a more quantitative direction if desired.

This case study introduces students to the complex field of immunology and the wide variety of host-pathogen interactions that drive evolutionary change.  The case begins with a basic overview of the phases of the immune response and how each contributes to host defense against an invading pathogen.  In order to delve deeper into each phase, students explore the metaphor of a battle in which a host and pathogen are locked in combat in order to understand the individual components of the immune response.  Once students successfully understand how the immune system works in general, they are then asked to think creatively about how a pathogen that wants to survive could evolve to evade the immune response, and to find concrete examples in the literature.  The overall goal is for students to gain a deeper understanding of the immune response and how host-pathogen interactions drive coevolution of both host immune components and the pathogen itself. The case was originally designed for an introductory biology course, but can easily be adapted for use in a variety of different courses and levels.