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The heavy impact on the environment of meat production was known but the research shows a new scale and scope of damage, particularly for beef. The popular red meat requires 28 times more land to produce than pork or chicken, 11 times more water and results in five times more climate-warming emissions. When compared to staples like potatoes, wheat, and rice, the impact of beef per calorie is even more extreme, requiring 160 times more land and producing 11 times more greenhouse gases.

In 1977, a University of Oxford statistician named Richard Peto pointed out a simple yet puzzling biological fact: We humans should have a lot more cancer than mice, but we don't. Dr. Peto's argument was beguilingly simple. Every time a cell divides, there's a small chance it will gain a mutation that speeds its growth. Cells that accumulate several of these mutations may become cancerous. The bigger an animal is, the more cells it has, and the longer an animal lives, the more times its cells divide. We humans undergo about 10,000 times as many cell divisions as mice - and thus should be far more likely to get cancer.

In a first, scientists led by Kamel Khalili, director of the Comprehensive NeuroAIDS Center at Temple University, report in the journal Gene Therapy that they have for the first time successfully eliminated HIV genes from the genomes of mice and rats infected with the virus.

The next time you look in a mirror, think about this: In many ways you're more microbe than human. There are 10 times more cells from microorganisms like bacteria and fungi in and on our bodies than there are human cells. But these tiny compatriots are invisible to the naked eye. So we asked artist Ben Arthur to give us a guided tour of the rich universe of the human microbiome.

In this directed case study students follow a nurse practitioner and work with a diagnostics team to determine what is wrong with Tristan, an infant who comes to the clinic with multiple bruises. Students are given background and patient history, and are then given results of various blood tests ordered by the diagnostics team. The exercise emphasizes the physiological process of coagulation and the importance of various clotting factors, especially factor VIII. Students will be introduced to results from several blood tests, including: complete blood count, partial thromboplastin time, prothrombin time, metabolic panel, and factor VIII assay. The patient is ultimately diagnosed with severe hemophilia A and the case then introduces students to this disorder, the genetic determinants, the incidence, and ways to manage the disease. The data in this case are real and the story represents the medical history of an actual patient. Originally developed for pre-nursing students, this activity would also be suitable for majors in physiology or pre-medical students; it could also be used in an introductory genetics or biology course.

Methane's potency is one reason why environmentalists are so concerned about natural gas leaks. The Porter Ranch disaster in southern California spewed more than 200 million pounds of methane before it was finally plugged in mid-February. But each year, cows in the U.S. burp out 65 times more gas than was released in the now infamous leak. Globally, about a quarter of methane pollution comes from livestock. Hristov and his team study ways to reduce those emissions, so they have gotten very good at quantifying the amount their cows exhale. Prompted by some extra snacks, cow number 2050 ducks her head into a hooded machine that records the amount of methane, hydrogen, and carbon dioxide in her burps. During experiments, the scientists take eight measurements from each cow over several days. In a few months, this gives a snapshot of just how much methane the animals churn out -- and whether particular interventions work to slash that pollution.

For anyone with a deep, enduring faith in the meaning of nature, it may come as something of a shock to learn that the word "natural" means nothing at all-at least when it comes to the business of marketing processed food. Every year, U.S. corporations sell tens of billions of dollars worth of food products labeled as "natural." Yet, to this day, the Food and Drug Administration has never formally defined the term. The word is a kind of orphan child, undefined by government, misused by industry and without a provenance or a use for the average American consumer.

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.

For the first time, biologists have succeeded in growing human stem cells in pig embryos, shifting from science fiction to the realm of the possible the idea of developing human organs in animals for later transplant.

This case study was inspired by the Zika virus outbreak that occurred around the time of the 2016 Olympic Games. Many athletes were fearful of attending because of the link between Zika virus infection and microcephaly in infants. This concern, however, ran contrary to reports suggesting that the risk of athletes and other travelers becoming infected was remarkably low. Jessica, a fictional Olympic equestrian and the main character of the case, was unfortunately very unlucky and contracted Zika virus near the time of the Games. She ended up enduring negative health complications likely as a consequence of the infection.  This case was designed to be implemented in the nervous system unit of a human biology or anatomy and physiology course. The case is also appropriate for microbiology and public health courses.   Students are expected to have foundational knowledge in viral life cycles, and will explore disruptions in neurotransmission as well as abnormal fetal brain development.

19 min TED talk on climate change. Photographer James Balog shares new image sequences from the Extreme Ice Survey, a network of time-lapse cameras recording glaciers receding at an alarming rate, some of the most vivid evidence yet of climate change.

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.

A data collection and analysis lesson that examines selection for coat color in pocket mouse populations on different color substrates over time.

But those measures did little to curb the smog the first time. Toxic air cloaked Beijing until strong winds blew the pollutants south. The main source of foul air in the capital comes from coal-burning factories in surrounding provinces, not from activity in the city itself, and cities in those provinces did not take the same drastic emergency measures that Beijing did. Many parts of northern China, including the provinces of Hebei, Henan and Shanxi, regularly have air quality that is worse than that of Beijing.

In the 1950s, Idaho sheep ranchers had a problem. About a quarter of their lambs were being born dead or deformed-sometimes with a single eye centered in the middle of their forehead, like the Cyclops of Greek legend, or missing their upper jaw. There were times when the pregnant ewes couldn't give birth at all, carrying the mutated fetuses until they were surgically delivered or the ewes themselves died. Unbeknownst to the farmers, the cause was a poisonous plant, western false hellebore (Veratrum californicum). Eventually, the plant would inspire a successful cancer therapy-but at the time, the sheep were what mattered.

The DNA in just one of your cells gets damaged tens of thousands of times per day. Because DNA provides the blueprint for the proteins your cells need to function, this damage can cause serious issues-including cancer. Fortunately, your cells have ways of fixing most of these problems, most of the time. Monica Menesini details the processes of DNA damage and repair.

This two-minute video provides brief background on the use of zebrafish as a model in studying animal development, before showing a time-lapse sequence of a fertilized zebrafish egg developing into a larva.  The video includes some annotations that help orient the viewer during the time-lapse sequence.  Teachers might want to mute the narration beginning at 0:42 min to avoid giving students too much information.  This phenomenon could stimulate the following driving questions: How does the zebrafish develop from one cell to the many cells that make up the larva? How do the zebrafish cells divide? How are the developing zebrafish cells similar and different from each other? If all cells in the zebrafish develop from the same original cell, then how do some cells develop differently than others? How are cell division and growth related? 

Teaching K-12 Science and Engineering During a Crisis aims to describe what high quality science and engineering education can look like in a time of great uncertainty and to support practitioners as they work toward their goals. This book includes guidance for science and engineering practitioners - with an emphasis on the needs of district science supervisors, curriculum leads, and instructional coaches. Teaching K-12 Science and Engineering During a Crisis will help K-12 science and engineering teachers adapt learning experiences as needed to support students and their families dealing with ongoing changes to instructional and home environments and at the same time provide high quality in those experiences.

With that in mind, we formed the first storylining working group, which is open to anyone to join at any time. The group is led by Dr. Jason Crean and Mrs. Kristin Rademaker and meets once a month to maintain that open collaboration.  We are able to offer Professional Development Credits to participants with an open-door policy.    We began this project with 3 goals in mind: Train educators in three-dimensional learning, teaching, and coherent curricular design through sustained collaborative work and by both experiencing and doing it themselves;  Create coherent storylines, including embedded three-dimensional assessment pieces that will evolve over time through continuous feedback from pilot teachers; and most of all Share our work- for teachers, by teachers, for free-  with any stakeholders interested in making the fundamental shift towards a three-dimensional classroom. 

Symbiotic relationships are interactions between species that live closely with each other and are commonly separated into three types: parasitism, mutualism, and commensalism. Students are often under the impression that these types are distinct and mutually exclusive, but on closer examination some interactions appear to be at times mutualistic, at other times parasitic. Is it perhaps better to think of mutualism and parasitism as two ends of a sliding scale, with commensalism in the middle? In this case study, students consider this question by examining what is often considered to be a classic example of mutualism existing between oxpecker birds and African savanna large mammals. After students examine data from a research study on oxpecker behavior, they then apply a more nuanced understanding of species interactions to a set of additional scenarios. The learning objectives for the case align with the Four-Dimensional Ecology Education Framework. The case was written for an upper-level undergraduate ecology course, but could easily be adapted for an introductory biology course.