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A team of scientists, in a groundbreaking analysis of data from hundreds of sources, has concluded that humans are on the verge of causing unprecedented damage to the oceans and the animals living in them. "We may be sitting on a precipice of a major extinction event," said Douglas J. McCauley, an ecologist at the University of California, Santa Barbara, and an author of the new research, which was published on Thursday in the journal Science.

The most venomous animal on the planet isn't a snake, a spider, or a scorpion; it's a snail-a cone snail, to be precise. The Conus genus boasts a large variety of marine snails that have adopted an equally diverse assortment of venoms. Online today in the Proceedings of the National Academy of Sciences, researchers report an especially interesting addition to the animals' arsenal: insulin. According to the paper, this marks the first time insulin has been discovered as a component of venom.

Almost 80% of all antibiotics in the United States aren't taken by people. They're given to cows, pigs, and chickens to make them grow more quickly or as a cheap alternative to keeping them healthy. These drugs could give rise to superbugs-bacteria that can't be treated with modern medicine-and things are only getting worse. In 2013, more than 131,000 tons of antibiotics were used in food animals worldwide; by 2030, it will be more than 200,000 tons. In a paper published today in Science, epidemiologist Thomas Van Boeckel of the Swiss Federal Institute of Technology in Zurich and colleagues outline the growing threat-and what can be done about it. Boeckel spoke to us about his team's work. This interview has been edited for clarity and length.

Its accuracy has made DNA evidence virtually unassailable. A landmark report published by the National Research Council in 2009 dismissed most forensics as unproven folk-wisdom but singled out DNA as the one forensic science worthy of the name. Yet in recent years Hampikian and other geneticists have begun to question the technology. Thanks to a series of advances-including the polymerase chain reaction, which can multiply tiny amounts of DNA-it's now possible to detect DNA at levels hundreds or even thousands of times lower than when DNA fingerprinting was developed in the 1980s. Investigators can even collect "touch DNA" from fingerprints on, say, a glass or a doorknob. A mere 25 or 30 cells will sometimes suffice. This heightened sensitivity can easily create false positives

American Museum of Natural History Explore the natural world with Science Bulletins; our documentary Feature Stories, Data Visualizations, and News updates focus on recent discoveries and new technologies in astrophysics, Earth science, biodiversity, and human health and evolution.

This case study synthesizes students' knowledge of the central dogma and cell structure by examining a rare health disorder in order to understand protein targeting and its medical consequences. Students first identify the molecular alteration in affected members of a family with renal Fanconi syndrome as reported in the New England Journal of Medicine (2014). Students then use an online bioinformatics tool to analyze the wildtype and mutant proteins and examine their subcellular localization. Finally, students use this information to explain the symptoms of affected family members. The case is delivered with a PowerPoint presentation that includes a selection of brainstorming prompts and "clicker questions." Students complete a worksheet (included in the teaching notes) before class, making the activity suitable for a flipped classroom. A second worksheet (also included in the teaching notes) is completed during class. The case is written for an introductory biology course for majors, but could also be used as a unit capstone in a non-majors human biology course; the case is also scalable to upper division courses in physiology that specifically explore kidney function.

The war against malaria has a new ally: a controversial technology for spreading genes throughout a population of animals. Researchers report today that they have harnessed a so-called gene drive to efficiently endow mosquitoes with genes that should make them immune to the malaria parasite-and unable to spread it. On its own, gene drive won't get rid of malaria, but if successfully applied in the wild the method could help wipe out the disease, at least in some corners of the world. The approach "can bring us to zero [cases]," says Nora Besansky, a geneticist at the University of Notre Dame in South Bend, Indiana, who specializes in malaria-carrying mosquitoes. "The mosquitos do their own work [and] reach places we can't afford to go or get to."

Post the link to the Science News article "Life on Earth may have begun in hostile hot springs" to your virtual classroom. Ask students to read the article for homework and prepare for online class by answering the first question. Before the class meets, provide the students with the links to all articles they will need for class. Class discussion can be conducted via Zoom; the research and recipe-building components can be conducted in breakout rooms.

In the second film of the Great Transitions trilogy, paleontologist Julia Clarke takes us on a journey to uncover the evidence that birds descended from dinosaurs. The discovery of Archaeopteryx in a quarry in Germany in the early 1860s provided the first clue that birds descended from reptiles. But what kind of reptile? In the last 40 years, scientists have identified many shared features between birds and two-legged carnivorous dinosaurs called theropods. The film illustrates many of the practices of science, including asking important questions, formulating and testing hypotheses, analyzing and interpreting evidence, and revising explanations as new evidence becomes available.

This case study follows a young cystic fibrosis (CF) patient named Lucas. Through Lucas's story and interactions between his parents and pediatrician, students learn about the scientific background and basis of CF. By reviewing email correspondence between Lucas's parents and various doctors, students gain an overview of CF research. CF has become a model disease in certain undergraduate biology classrooms due to its relatively clear mechanism and genetic basis. This case asks students to come up with their own ideas to improve on an existing line of research - gene therapy - in treating CF. During the process, students will gain a better appreciation of the innovative nature of science and develop research skills such as finding, understanding and analyzing primary literature. The activity was originally designed for first- and second-year students as part of an extracurricular case competition, but may be used for any undergraduate biology level. The case assumes basic (high school level) knowledge of genetics, biochemistry, cell biology and physiology.

TeachEngineering.org is a collaborative project between faculty, students and teachers associated with five universities and the American Society for Engineering Education, with NSF National Science Digital Library funding. TeachEngineering.org is a searchable, web-based digital library collection populated with standards-based engineering curricula for use by K-12 teachers and engineering faculty to make applied science and math (engineering) come alive in K-12 settings. The TeachEngineering collection provides educators with *free* access to a growing curricular resource of multi-week units, lessons, activities and living labs. Initiated by the merging of K-12 engineering curricula created by four universities, the collection continues to grow and evolve over time with new additions from other universities, and input from teachers who use the curricula in their classrooms.

A genetic "crystal ball" can predict whether certain people will respond effectively to the flu vaccine. Nine genes are associated with a strong immune response to the flu vaccine in those aged 35 and under, a new study finds. If these genes were highly active before vaccination, an individual would generate a high level of antibodies after vaccination, no matter the flu strain in the vaccine, researchers report online August 25 in Science Immunology. This response can help a person avoid getting the flu.

In a unique twist on human genomics studies that seek to identify genetic variants linked to human disease, researchers have combined whole-exome sequencing of 50,726 adults with the individuals' long-term electronic health record (EHR) data. The effort, by researchers at the Geisinger Health System in Pennsylvania and Regeneron Genetics Center, a subsidiary of New York-based Regeneron Pharmaceuticals, has yielded novel disease-linked variants, including loss-of-function alleles. The team behind the project, called DiscovEHR, has also found that about one in 30 of the individuals harbors a deleterious genetic variant for which a screen or treatment already exists. The group's analysis is described in two papers published today (December 22) in Science.

Despite existing for hundreds of years, the science of classification is far from dead. Classification of many species, old and new, continues to be hotly disputed as scientists find new information or interpret facts in new ways. Arguments are fierce and species do change names, but only after a wealth of information has been gathered to support such a big step. One of the new reasons why species are being re-evaluated is because of DNA analysis.

This case study is centered on a real scenario from 2013 in which the Kickstarter fundraising platform included a fundraising proposal from a group wanting to use synthetic biology to make glowing plants. The proposal raised controversy because the Glowing Plant group offered to give away their genetically-modified glowing plant product to investors.  Kickstarter subsequently changed its policy to prevent use of genetically modified organisms as rewards or incentives to investors. This case study was developed for a college first-year seminar focused on the ethics of synthetic biology, and was introduced during the first week of the semester. The case uses the jigsaw teaching method to introduce students both to the mechanics of synthetic biology and to questions about how we should distribute the benefits and burdens associated with new or emerging technologies. It could be adapted for courses in introductory college biology, genetics or bioethics.

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 interrupted case study for the flipped classroom introduces the human microbiome from the perspective of one of its occupants, Heidi Helicobacter (Helicobacter pylori).  Heidi lives in the gut of Kristen, a college student, and discusses her fellow microbial inhabitants, functions of these various microbes, and alludes to factors that can disrupt the healthy human microbiome. Students prepare for class by viewing several brief videos and then discuss in class whether Kristen should undergo a fecal microbiota transplant to treat her Clostridium difficile infection.  A lab component has students model, using colored beads, how antibiotics can act as a selective agent for drug-resistant microbes such as C. difficile. The case concludes with Kristen about to give birth to a new baby several years later.  Students listen in as Kristen's microbes discuss the formation of the new baby's microbiome. The case has been used successfully in a general biology class and could easily be adapted for a microbiology, human physiology, ecology, or evolution course.

Why does a snake have 25 or more rows of ribs, whereas a mouse has only 13? The answer, according to a new study, may lie in "junk DNA," large chunks of an animal's genome that were once thought to be useless. The findings could help explain how dramatic changes in body shape have occurred over evolutionary history. Scientists began discovering junk DNA sequences in the 1960s. These stretches of the genome-also known as noncoding DNA-contain the same genetic alphabet found in genes, but they don't code for the proteins that make us who we are. As a result, many researchers long believed this mysterious genetic material was simply DNA debris accumulated over the course of evolution. But over the past couple decades, geneticists have discovered that this so-called junk is anything but. It has important functions, such as switching genes on and off and setting the timing for changes in gene activity. 

This case study examines a variety of biological factors that may have been involved in the 2013 dolphin "unusual mortality event" (UME) on the East Coast of the United States. The story follows a news reporter and four different scientists who are preparing their notes for speaking at a public hearing about the dolphin die-off event. After reading the story, students assume the roles of these scientists and use the jigsaw method to gather, analyze, and share information.  Due to the interdisciplinary nature of environmental toxicology, this case study exposes students to four main topics: ecology of ecosystems, endocrine system/chemical messaging, immune system function, and virus biology.

She wanted to understand the effects of mutations that the gene for p53 is prone to. In dozens of simulations, she and her colleagues tracked how common p53 mutations further destabilize the already floppy protein, distorting it and preventing it from binding to DNA. Some simulations also revealed something else: a fingerhold for a potential drug. Once in a while, a small cleft forms in the mutated protein's core. When Amaro added virtual drug molecules into her models, the compounds lodged in that cleft, stabilizing p53 just enough to allow it to resume its normal functions.