This Halloween, you’re not likely to see many trick-or-treaters dressed as spiders. Google Trends pegs “Spider” as the 87th most searched-for Halloween costume, right between “Hippie” and “The Renaissance.” But don’t let your guard down. Spiders are everywhere.

More than 46,000 species of spiders creepy crawl across the globe, on every continent except Antarctica. Each species produces a venom composed of an average of 500 distinct toxins, putting the conservative estimate of unique venom compounds at more than 22 million. This staggering diversity of venoms, collectively referred to as the venome, has only begun to be explored.

The outside of every cell on Earth—from the cells in your body to single-celled microorganisms—is blanketed with a coat of carbohydrates, or sugar molecules, that extend from the cell surface, branching off and bending as they interface with the extra-cellular space. The specific patterns in which these carbohydrates are arranged serve as an ID code that help cells recognize each other. For example, human liver cells have one pattern, while human red blood cells another. Certain diseases can even alter the pattern of surface carbohydrates, which is one way the body can recognize damaged cells. On foreign cells, including invading bacteria such as Streptococcus pneumoniae, the carbohydrate coat is even more distinct. Laura Kiessling, a professor of chemistry at the University of Wisconsin, Madison, studies how carbohydrate coats are assembled and how cells use these coats to tell friend from foe. The implications of her research suggest strategies for targeting tumors, fighting diseases of inflammation and, as she discusses in this video, developing new classes of antibiotics.

A 50-pound frog isn’t some freak of nature or a creepy Halloween prank. It’s a thought experiment conceived by Rebecca Heald, a cell biologist at the University of California, Berkeley , who is studying the factors that control size in animals. Heald’s “50-pound frog project” speaks to the power of evolution and to scientists’ ability to modify the physical characteristics of an organism by altering its genome. The project also incorporates many of Heald’s fascinating discoveries studying amphibian eggs and embryos. In amphibians, unlike in mammals, there are striking correlations among the size of the animals’ genomes (an organism’s complete set of genes) and several aspects of the animals’ size. For example, amphibians with large genomes tend to be bigger than those with smaller genomes. Larger genomes also correspond to larger cells and larger organelles (specialized cellular structures such as the nucleus). Heald has also demonstrated that these seemingly fixed parameters can be tweaked in the lab.

The world beneath our skin is full of movement. Hemoglobin in our blood grabs oxygen and delivers it throughout the body. Molecular motors in cells chug along tiny tubes, hauling cargo with them. Biological invaders like viruses enter our bodies, hijack our cells and reproduce wildly before bursting out to infect other cells. To make sense of the subcutaneous world, Janet Iwasa, a molecular animator at the University of Utah, creates “visual hypotheses”—detailed animations that convey the latest thinking of how biological molecules interact. “It’s really building the animated model that brings insights,” Iwasa told Biomedical Beat in 2014. “When you’re creating an animation, you’re really grappling with a lot of issues that don’t necessarily come up by any other means. In some cases, it might raise more questions, and make people go back and do some more experiments when they realize there might be something missing.” Iwasa has collaborated with numerous scientists to develop animations of a range of biological processes and structures . Recently, she’s undertaken an ambitious, multi-year project to animate HIV reproduction .

Like the athletes in Rio, the world’s most highly advanced microbial runners recently gathered in Charlestown, Massachusetts, to find out which ones could use chemical cues to most quickly navigate a maze-like microfluidic racecourse. The winners’ prize: credit for helping scientists learn more about how immune system cells navigate through the human body on their way to fight disease. The finalists were a group of soil-dwelling slime molds called Dictyostelium that were genetically engineered by a pair of Dutch biochemists to detect minuscule chemical changes in the environment. The racers used their enhanced sense of “smell” to avoid getting lost on their way to the finish line. While researchers have been racing the genetically souped-up microbes at annual events for a few years—another competition is scheduled for October 26—scientists have been studying conventional Dictyostelium for decades to investigate other important basic life processes including early development, gene function, self/non-self recognition, cell-type regulation, chemical signaling and programmed cell death.

You glide across an icy canyon where you meet smiling snowmen, waddling penguins and a glistening river that winds forever. You toss snowballs, hear them smash against igloos, then watch them explode in vibrant colors.

Back in the real world, a dentist digs around your mouth to remove an impacted tooth, a procedure that really, really hurts. Could experiencing a “virtual” world distract you from the pain? NIGMS grantees David Patterson and Hunter Hoffman show it can.

Patterson, a psychologist at the University of Washington (UW) in Seattle, and Hoffman, a UW cognitive psychologist, helped create the virtual reality program “Snow World” in an effort to reduce excessive pain experienced by burn patients. However, the researchers expect Snow World to help alleviate all kinds of pain, including pain experienced during dental procedures.