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Biologists have long puzzled about how evolutionary selection, known for its ruthless requirement for efficiency, allows the existence of males - when in so many species their only contribution to reproduction are spermatozoa. But research published today in Nature shows that sexual selection - when males compete and females choose over reproduction - improves population health and protects against extinction, even in the face of genetic stress from high levels of inbreeding.

This case study focuses on the relationship between evolution and plasticity using a hands-on, inquiry-based approach. Students view examples from the literature that illustrate the difference between nature and nurture, or the relative contributions of genes and the environment in shaping phenotypes. Using the Trinidadian guppy system as an example, students learn about seminal work in the field in addition to exploring quantitative genetic techniques used to partition phenotypic variance between genes (G) and the environment (E). They use real data from one of the publications cited in the case to graph reaction norms illustrating GxE interactions at the family and population level. The inquiry-based approach means that students are introduced to new concepts in a stepwise fashion, and asked to develop and build their understanding using causal, explanatory evidence. The case concludes with an exercise in which students apply their knowledge to a real conservation problem in Trinidad and Tobago, where guppies are native. This case would be appropriate for an upper level biology, genetics, or evolution course.

On September 15, the Washington University School of Medicine published a study in The American Journal of Psychiatry revealing that schizophrenia, commonly thought of as a single mental disorder, is actually a group of eight distinct afflictions. People with schizophrenia are typically diagnosed in their 20s, which is when symptoms (such as delusions and hallucinations) begin to manifest. The brain disorder affects about 1 percent of the population, and it is highly genetic: According to the NIH, having a relative diagnosed with schizophrenia increases one's chances of developing the disorder by 10 percent, while having an identical twin with the disorder raises the risk to 40 to 65 percent.

The Ebola epidemic that tore through West Africa in 2014 claimed 11,310 lives, far more than any previous outbreak. A combination of factors contributed to its savagery, among them a mobile population, crumbling public health systems, official neglect and hazardous burial practices. But new research suggests another impetus: The virus may have evolved a new weapon against its human hosts. In studies published on Thursday in the journal Cell, two teams of scientists report that a genetic mutation may have made Ebola more deadly by improving the virus's ability to enter human cells.

Why is the North American population of monarch butterflies declining? In 1999, a study published in the journal Nature suggested that a variety of genetically modified corn was killing these iconic butterflies. While it was later shown that the conditions in this study did not mirror those in the field, the results garnered a lot of media attention and many people today still believe that monarchs are being killed by GMOs. This case familiarizes students with the plight of the monarchs, encourages them to think about how to test the hypothesis that a toxin is responsible for their decline, and takes a critical look at several studies that investigated the role of Bt corn in the life cycle of monarchs. This interrupted case takes 60-90 min to complete, requires little to no science background, and can be used to explore the ecology and wildlife management of monarchs; risk assessment, toxicity, and exposure; experimental design, the scientific method, hypothesis, and critical thinking; or the relationship between science, the media and the public.

The 1000 Genomes Project is an international collaboration to produce an extensive public catalog of human genetic variation, including SNPs and structural variants, and their haplotype contexts. This resource will support genome-wide association studies and other medical research studies. The genomes of about 2500 unidentified people from about 25 populations around the world will be sequenced using next-generation sequencing technologies. The results of the study will be freely and publicly accessible to researchers worldwide. Further information about the project is available in the About tab. Information about downloading, browsing or using the 1000 Genomes data is available in the Data tab.

This video excerpt from NOVA examines the promise and realities of developing drugs designed to treat genetic disorders. The video presents the story of one patient, Michael McCarrick, whose lungs were devastated from years of suffering from cystic fibrosis. After researchers identified the gene involved in cystic fibrosis, it took decades to find ways to fortify the faulty protein responsible for the serious illness. While two drugs, including one called Kalydeco, offer a small number of patients hope that they will not have to endure a lung transplant, it may be years and several hundred million more development dollars before effective drugs are available for a wider population.

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.

The Virtual Biology Lab Project is designed to provide interactive activities that demonstrate ecological principles. We provide agent-based models that simulate classic ecological experiments or concepts across a wide range of ecological topics. Students manipulate experimental parameters and observe the results. These results are provided numerically and graphically and are reinforced with a visualization of the model's "world". The content is suitable for advanced high-school and college students.

This site has you covered, no matter what you teach. Each science subject is divided into major topics and resources are neatly categorized and numerous.