The Woolly Worm Festival is an event held each October since 1978 in Banner Elk and Avery County, North Carolina . The festival celebrates the supposed weather-predicting abilities of the woolly worm, also called "woolly bear" which is a caterpillar or larvae of the isabella tiger moth . Events include a caterpillar race.
31-556: The isabella tiger moth belongs to the subfamily Arctiinae which has 11,000 species around the world. Prior to settling in for winter, the woolly worm eats a variety of plants and then produces a kind of antifreeze which protects the creature from temperatures as low as -90 degrees Fahrenheit. This caterpillar seeks safety from bitter winter weather by sheltering under logs, boulders, boards, rocks, and other dark places until emerging from its "frozen" state in May. It's accepted by organizers of
62-517: A bear). Some species within the Arctiinae have the word "tussock"' in their common names because they have been misidentified as members of the Lymantriinae subfamily based on the characteristics of the larvae. The subfamily was previously classified as the family Arctiidae of the superfamily Noctuoidea and is a monophyletic group. Recent phylogenetic studies have shown that the group
93-500: A class of organic compounds that increase the output force of the heart and decrease its rate of contractions by inhibiting the cellular sodium-potassium ATPase pump . Their beneficial medical uses include treatments for congestive heart failure and cardiac arrhythmias ; however, their relative toxicity prevents them from being widely used. Most commonly found as secondary metabolites in several plants such as foxglove plants and milkweed plants , these compounds nevertheless have
124-423: A diverse range of biochemical effects regarding cardiac cell function and have also been suggested for use in cancer treatment. The general structure of a cardiac glycoside consists of a steroid molecule attached to a sugar ( glycoside ) and an R group. The steroid nucleus consists of four fused rings to which other functional groups such as methyl , hydroxyl , and aldehyde groups can be attached to influence
155-466: A tight spiral or drop from their perch suspended by a strand of silk. Isabella tiger moths ( Pyrrharctia isabella ) overwinter in the caterpillar stage. They can survive freezing at moderate subzero temperatures by producing a cryoprotectant chemical. The larvae of another species, Phragmatobia fuliginosa , may be found on snow seeking a place to pupate. Species in Arctic and temperate belts overwinter in
186-624: A vertical string attached to cardboard on the backboard of a flatbed trailer. People are allowed to 'holler' and whistle to encourage their worm to race. Each heat consists of 20 worms and races continue all day until the grand final at about 4:00 p.m. The winning worm is announced as official forecaster, and its owner wins a monetary prize. The festival proceeds after expenses are distributed for support of community efforts and charities. 36°09′47″N 81°52′12″W / 36.16293°N 81.86988°W / 36.16293; -81.86988 Arctiinae The Arctiinae (formerly called
217-441: Is characterized by an inability to pump enough blood to support the body, possibly due to a decrease in the volume of the blood or its contractile force . Treatments for the condition thus focus on lowering blood pressure , so that the heart does not have to exert as much force to pump the blood, or directly increasing the heart's contractile force, so that the heart can overcome the higher blood pressure. Cardiac glycosides, such as
248-547: Is most closely related to litter moths Herminiinae and the Old World Aganainae , which are subfamilies of the family Erebidae . The Arctiidae as a whole have been reclassified to represent this relationship. The family was lowered to subfamily status as the Arctiinae within the Erebidae. The subfamilies and tribes of Arctiidae were lowered to tribes and subtribes, respectively, of this new Arctiinae to preserve
279-624: Is released from the SR of cardiac muscle cells. Toxicity also results in changes to heart chronotropic activity, resulting in multiple kinds of dysrhythmia and potentially fatal ventricular tachycardia . These dysrhythmias are an effect of an influx of sodium and decrease of resting membrane potential threshold in cardiac muscle cells. When taken beyond a narrow dosage range specific to each particular cardiac glycoside, these compounds can rapidly become dangerous. In sum, they interfere with fundamental processes that regulate membrane potential . They are toxic to
310-867: Is supposed to mean a harsh winter. However, the relative width of the black band varies among instars , not according to weather. The mythical qualities attributed to woolly bears in America have led to such things as the Woollybear Festival in Ohio, the Woolly Worm Festival in Beattyville , Kentucky and the Woolly Worm Festival in Banner Elk , North Carolina . Cardiac glycosides Cardiac glycosides are
341-645: The American Northeast and South hold that "woolly bears" (or "woolly worms" in the South) help humans predict the weather, similar to the groundhog . The forthcoming severity of a winter may be indicated by the amount of black on the Isabella tiger moth 's caterpillar—the most familiar woolly bear in North America. More brown than black is said to mean a mild winter, while more black than brown
SECTION 10
#1732800965396372-646: The sarcoplasmic reticulum (SR) via the SERCA2 transporter. Raised calcium stores in the SR allow for greater calcium release on stimulation, so the myocyte can achieve faster and more powerful contraction by cross-bridge cycling. The refractory period of the AV node is increased, so cardiac glycosides also function to decrease heart rate. For example, the ingestion of digoxin leads to increased cardiac output and decreased heart rate without significant changes in blood pressure; this quality allows it to be widely used medicinally in
403-550: The E2-P transition state, so that sodium cannot be extruded: intracellular sodium concentration therefore increases. With regard to potassium ion movement, because both cardiac glycosides and potassium compete for binding to the ATPase pump, changes in extracellular potassium concentration can potentially lead to altered drug efficacy. Nevertheless, by carefully controlling the dosage, such adverse effects can be avoided. Continuing on with
434-545: The Lepidoptera, but the location and structure is distinctive to the subfamily. Other distinctive traits are particular setae (hairs) on the larvae, wing venation, and a pair of glands near the ovipositor. The sounds are used in mating and for defense against predators. Another good distinguishing character of the subfamily is presence of anal glands in females. Many species retain distasteful or poisonous chemicals acquired from their host plants. Some species also have
465-556: The North Carolina woolly worm festival that the color of the worm's thirteen body segments or stripes can be read and interpreted as a forecaster of the severity of coming winter. Although not everyone recognizes the woolly worm as an accredited weather forecaster, the worm is held in esteem by festival celebrants because of its proclaimed 80-85 percent accuracy rate in predictions. Each year attendance at this mountain celebration averages 15,000-20,000 people. It's been featured in
496-484: The ability to make their own defenses. Common defenses include cardiac glycosides (or cardenolides ), pyrrolizidine alkaloids , pyrazines , and histamines . Larvae usually acquire these chemicals, and may retain them in the adult stage, but adults can acquire them, too, by regurgitating decomposing plants containing the compounds and sucking up the fluid. Adults can transfer the defenses to their eggs, and males sometimes transfer them to females to help with defense of
527-467: The cardiac output of the heart, cardenolides are more commonly used medicinally, primarily due to the widespread availability of the plants from which they are derived. Cardiac glycosides can be more specifically categorized based on the plant they are derived from, as in the following list. For example, cardenolides have been primarily derived from the foxglove plants Digitalis purpurea and Digitalis lanata , while bufadienolides have been derived from
558-463: The cardiovascular, neurologic, and gastrointestinal systems, these three systems can be used to determine the effects of toxicity. The effect of these compounds on the cardiovascular system presents a reason for concern, as they can directly affect the function of the heart through their inotropic and chronotropic effects. In terms of inotropic activity, excessive cardiac glycoside dosage results in cardiac contractions with greater force, as further calcium
589-495: The caterpillars and adults are active during the daytime, but most species of this taxon are night-flying. Moths are attracted by light, but one species, Borearctia menetriesii , never comes to the light. Basking to accelerate digestion is common in the larval stages, and social behaviour may range from solitary to gregarious. Like most Lepidoptera, larvae produce a small silk pad before each moult, in which their prolegs are engaged. If disturbed, woolly bear caterpillars roll into
620-584: The commonly used digoxin and digitoxin, deal with the latter, due to their positive inotropic activity. On the other hand, cardiac arrhythmia are changes in heart rate, whether faster ( tachycardia ) or slower ( bradycardia ). Medicinal treatments for this condition work primarily to counteract tachycardia or atrial fibrillation by slowing down heart rate, as done by cardiac glycosides. Nevertheless, due to questions of toxicity and dosage, cardiac glycosides have been replaced with synthetic drugs such as ACE inhibitors and beta blockers and are no longer used as
651-439: The eggs. Larval "hairs" may be stinging in some species, due to histamines their caterpillars make. The insects advertise these defenses with aposematic bright coloration, unusual postures, odours, or in adults, ultrasonic vibrations. Some mimic moths that are poisonous or wasps that sting. The ultrasound signals help nocturnal predators to learn to avoid the moths, and for some species can jam bat echolocation . Many of
SECTION 20
#1732800965396682-523: The family Arctiidae ) are a large and diverse subfamily of moths with around 11,000 species found all over the world, including 6,000 neotropical species. This subfamily includes the groups commonly known as tiger moths (or tigers), which usually have bright colours, footmen , which are usually much drabber, lichen moths , and wasp moths . Many species have "hairy" caterpillars that are popularly known as woolly bears or woolly worms . The scientific name Arctiinae refers to this hairiness (Gk. αρκτος =
713-400: The internal structure of the group. Many genera are classified into these tribes, while others remain unclassified ( incertae sedis ) . The most distinctive feature of the subfamily is a tymbal organ on the metathorax . This organ has membranes that are vibrated to produce ultrasonic sounds. They also have thoracic tympanal organs for hearing, a trait with a fairly broad distribution in
744-541: The larval stage. Some tiger moths produce ultrasonic clicks in response to the echolocation of bats to protect themselves. Many species are polyphagous in the larval stage. Monophagous species, such as the cinnabar moth ( Tyria jacobaeae ), are scarce. Although abundant, few species in this subfamily are of economic importance. Even the fall webworm , an abundant and highly polyphagous tree-feeding species that has spread from North America to Asia and Europe, does not do lasting damage to healthy hosts. Local folklore of
775-452: The mechanism, raised intracellular sodium levels inhibit the function of a second membrane ion exchanger, NCX , which is responsible for pumping calcium ions out of the cell and sodium ions in at a ratio of 3Na / Ca . Thus, calcium ions are also not extruded and will begin to build up inside the cell as well. The disrupted calcium homeostasis and increased cytoplasmic calcium concentrations cause increased calcium uptake into
806-408: The molecule allows it to be classified as either a cardenolide or bufadienolide. Cardenolides differ from bufadienolides due to the presence of an "enolide," a five-membered ring with a single double bond, at the lactone end. Bufadienolides, on the other hand, contain a "dienolide," a six-membered ring with two double bonds, at the lactone end. While compounds of both groups can be used to influence
837-407: The overall molecule's biological activity. Cardiac glycosides also vary in the groups attached at either end of the steroid. Specifically, different sugar groups attached at the sugar end of the steroid can alter the molecule's solubility and kinetics; however, the lactone moiety at the R group end only serves a structural function. In particular, the structure of the ring attached at the R end of
868-691: The primary medical treatment for such conditions. Depending on the severity of the condition, though, they may still be used in conjunction with other treatments. From ancient times, humans have used cardiac-glycoside-containing plants and their crude extracts as arrow coatings, homicidal or suicidal aids, rat poisons, heart tonics, diuretics and emetics, primarily due to the toxic nature of these compounds. Thus, though cardiac glycosides have been used for their medicinal function, their toxicity must also be recognized. For example, in 2008 US poison centers reported 2,632 cases of digoxin toxicity , and 17 cases of digoxin-related deaths. Because cardiac glycosides affect
899-531: The treatment of cardiac arrhythmias. Cardiac glycosides were identified as senolytics : they can selectively eliminate senescent cells which are more sensitive to the ATPase-inhibiting action due to cell membrane changes. Cardiac glycosides have long served as the main medical treatment to congestive heart failure and cardiac arrhythmia , due to their effects of increasing the force of muscle contraction while reducing heart rate. Heart failure
930-482: The venom of the cane toad Rhinella marina (formerly known as Bufo marinus ), from which they receive the "bufo" portion of their name. Below is a list of organisms from which cardiac glycosides can be derived. Cardiac glycosides affect the sodium-potassium ATPase pump in cardiac muscle cells to alter their function. Normally, these sodium-potassium pumps move potassium ions in and sodium ions out. Cardiac glycosides, however, inhibit this pump by stabilizing it in
961-513: The world-famous Farmers' Almanac and the Kiwanis International Magazine . Presiding over the yearly festival is a Master of Ceremonies. With the help of the festival's mascot Merriweather, the M.C. is responsible for ensuring festival rules are rigorously kept, in particular in regard to the caterpillar race. About 1200 worms are entered to compete, in at least 50 heats. During each heat worms must race 42 inches up