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This set of mini cases on the ecology of eastern cottontail rabbits is designed to give students practical experience using statistics in a scientific context. Given a dataset and experimental design, groups of students are asked to play the part of a wildlife management researcher to determine the results for each study. Students practice the scientific process and gain experience making hypotheses and predictions, choosing an appropriate statistical test, interpreting and displaying results, and presenting data to others. Students choose between four basic, commonly used, statistical tests (t-test, one-way ANOVA, linear regression, and Chi-square test), and justify their choices. This activity was developed for undergraduate level students and is applicable to biology courses, particularly those dealing with ecology or management. The case is designed for student groups, but could be modified into clicker questions or individual assignments.

Exploratory data analysis and common statistical assumptions in biology

Population statistics are like crystal balls -- when examined closely, they can help predict a country's future (and give important clues about the past). Kim Preshoff explains how using a visual tool called a population pyramid helps policymakers and social scientists make sense of the statistics, using three different countries' pyramids as examples.

n this interrupted case study, students learn about the influence of early fetal nutritional conditions on the expression of genes related to metabolism and growth. Beginning with the true event of a food and fuel embargo that led to famine in the western Netherlands toward the end of World War II, students learn about the historical background of the Dutch Hunger Winter and its social impact. Using real data from the study conducted by Heijmans and coauthors (2008), students then compare the methylation level of a specific gene between individuals conceived during the famine and their unaffected siblings, and how changes in the expression of this metabolically important gene may impact the risk of developing type 2 diabetes. Supported by other studies on mice and in humans, students conclude that in utero events may impact the health of individuals later in life through epigenetic mechanisms. The case is ideally suited for a molecular or cell biology course, but is also appropriate for an introductory biology course in which students have an understanding of descriptive statistics, interpretation of statistical test results, eukaryotic gene structure, and regulation of gene expression.

In this video Paul Andersen explains how to run the student's t-test on a set of data. He starts by explaining conceptually how a t-value can be used to determine the statistical difference between two samples. He then shows you how to use a t-test to test the null hypothesis. He finally gives you a separate data set that can be used to practice running the test.

This interrupted case study introduces basic modeling to investigate a decline in an American marten population on an island in Southeast Alaska. Two summer field technicians working on a long-term field ecology project for one of their professors notice that there are fewer marten captures this year. Through discussions with their professor, conversations with a local fur trapper, and based on their own observations, they develop a plan to model the population and the potential causes of the decline to solve the mystery. Students use Excel or other database software along with life tables and introductory population ecology to investigate three potential causes of the marten population decline. This case was developed for use in an environmental science or wildlife management course but could also be used in an advanced science high school course or general ecology course. It would be beneficial for students to have some background in statistics including how to interpret R-squared values, p-values, and 95% confidence intervals.

TinkerPlots is a data visualization and modeling tool developed for use by middle school through university students. TinkerPlots can be used to teach grades 4 and up in subjects including math, statistics, social science, or physical or biological science

TinkerPlots is a data visualization and modeling tool developed for use by middle school through university students. TinkerPlots can be used to teach grades 4 and up in subjects including math, statistics, social science, or physical or biological science

Six years ago, Yale University's Stephen Stearns and colleagues took advantage of a long-running study in Framingham, Massachusetts, to assess whether the effects of natural selection could be discerned among the people in the multigenerational study population. Over the last seven decades, public-health researchers have been monitoring the residents of Framingham, noting their vital statistics as well as blood sugar and cholesterol levels to understand the factors that lead to heart disease. As the initial group of research subjects got older, the study started to include their children, and then their grandchildren. The records provide a unique view of the health of a segment of the American population since 1948.

Index page for all of Mr. Anderson's most excellent and easy to understand videos for every biology, chemistry, A&P, earth science, physics, and statistics topic imaginable.

But did they actually live longer? The answer is yes! The average lifespan of monkeys on a regular diet is approximately 26 years, but the CR monkeys lived on average 3 years longer, a whopping 10 percent increase. The statistics suggest at any point in time, the control monkeys had 2.9 times the rate of death from age-related causes compared to those on a CR diet.

Select type of data to graph and view changes in data over time for selected cancer type or subpopulations.

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.

In a paper this week in Science, Vogelstein and Cristian Tomasetti, who joined the biostatistics department at Hopkins in 2013, put forth a mathematical formula to explain the genesis of cancer. Here's how it works: Take the number of cells in an organ, identify what percentage of them are long-lived stem cells, and determine how many times the stem cells divide. With every division, there's a risk of a cancer-causing mutation in a daughter cell. Thus, Tomasetti and Vogelstein reasoned, the tissues that host the greatest number of stem cell divisions are those most vulnerable to cancer. When Tomasetti crunched the numbers and compared them with actual cancer statistics, he concluded that this theory explained two-thirds of all cancers.

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.

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.

Learn about the latest statistics and how the FDA is addressing e-cigarette use among youth in this special message to teachers from the FDA Commissioner.

An innovative new breeding simulation helps reveal genetic ratios in offspring. With the heredity level of the ConnectedBio Multi-Level Simulation (MLS), students breed pairs of mice with different fur colors and observe the phenotypic ratios in the resulting offspring. The goal of this activity is to demystify the science behind Punnett Squares and encourage students to explore data and statistical representations in genetics and heredity.

Paul Andersen shows you how to calculate the ch-squared value to test your null hypothesis. He explains the importance of the critical value and defines the degrees of freedom. He also leaves you with a problem related to the animal behavior lab. This analysis is required in the AP Biology classroom.

In this interrupted case study students analyze the complexities surrounding identification and confirmation of cancer clusters. The case challenges students to consider the evidence from two different perspectives; a local family physician representing the community, and a cluster investigation officer who has worked on several cancer cluster investigations. This case was inspired by the discussion about a possible cancer cluster in Clyde, Ohio, where around 20 cases of childhood cancer since 2001 fueled public concern, leading to an investigation by the Ohio department of health in 2006. This case was designed for introductory courses in biology and environmental sciences, taken by both science majors and non-science majors. In addition to introductory college classes, this case could also be used in advanced high school biology classes.