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Why are cicadas so noisy? Our editors will review what you’ve submitted and determine whether to revise the article. Ah, summer. In many parts of the world, summer is the time of year when the cicadas are buzzing so loudly that you can hardly hear yourself think. Amid the din, two thoughts come to mind: Why are the cicadas carrying on so loudly? And how on earth are they able to achieve such an ear-shattering volume? In North America, most of the various species of cicadas that you hear are known as dog-day cicadas. The sound is produced only by males, mostly for the reasons you might imagine. There are congregational songs, in which males synchronize their calls. The choruses establish territory and attract females. In addition, there is a courting call that is usually produced prior to copulation. The songs of the cicada are affected by weather fluctuations. Generally speaking, cicadas like sunlight and warmth, but too much heat or too much coolness will quiet them down a bit.

Different species prefer different times of day, and each of the 3,000 or so species has a distinct sound. One theory for why the songs are so loud is that the songs may deter predators. The loudest group of cicadas are the periodical ones-those that emerge every 13 years and those that appear every 17 years-probably because there are so many more of them than the annual ones. Cicadas are able to produce these sounds because they possess an organ that is almost unique among insects, the tymbal organ. Each male cicada has a pair of these circular ridged membranes on the back and side surface of the first abdominal segment. Contraction of a tymbal muscle attached to the membrane causes it to bend, producing a clicking sound. The tymbal springs back when the muscle is relaxed. The frequency of the contractions of the tymbal muscle range from 120 to 480 times a second, Prime Boosts Official which is fast enough to make it sound continuous to the human ear. Cicadas also have air sacs that have resonant frequencies comparable to tymbal vibration frequencies, thus amplifying the sound and producing that crescendo of high-pitched buzzing that is the characteristic sound of late summer.

Can Skinny Legs Get Bigger? How to Get Bigger Thighs? Can You Gain Muscle from More Reps Without Weights? How Often Should I Train Legs to Get Them Bigger? How Long Will It Take for My Legs to Get Bigger? Along with a bigger, stronger chest, shirt-straining arms and perfectly carved six-pack abs, most guys want their leg muscles to really pop. Contrary to what you might think, building bigger legs without a gym full of equipment isn't impossible. Below, we showcase how you can pump up your legs with little or no weights, so no squirming under a deep barbell squat or Prime Boosts Official tearing a deadlift from the floor See details necessary. In fact, all you need is a small amount of room and a shed load of tenacity. To help you learn how to get bigger legs (calves, quads, hamstrings and more all included), we tapped up personal trainer Alex Crockford to draw you a personal blueprint to getting stacked down below.

Check this out workout is a home workout using no equipment other than usual things you'll find at home,' explains Crockford. But just because it's a weight-free workout, it doesn't mean it'll be a walk in the park. You need to feel it working, so if it’s too easy you can add weight with home dumbbells or anything heavy enough at home,' continues Crockford. Sounds like a win-win. How to do it: Standing tall and keeping your chest up at all times, take a long step forward with one leg, bending your front knee until the back knee touches the ground. Stand up explosively, pause and repeat with the other leg, moving forward. Reps: 12 Sets: 3 Rest: No rest, go straight into squat jumps. How to do it: Standing tall with your feet shoulder-width apart, keep your chest up and sink your hips back, before bending your knees to drop your thighs until they are at least parallel to the floor.

Push through the heels back to standing. Reps: 12 Sets: 3 Rest: 30 secs after each superset. How to do it: Stand straight with your arms across your chest and your feet shoulder-width apart. Lower yourself into a squat position until your thighs are parallel to the floor. Push up explosively from your feet keeping your arms folded as you jump up. Immediately jump again when you return to the squat position. How to do it: Stand facing away from bench with one leg resting on it, laces down. Squat down with your standing leg until the knee of your trailing leg almost touches the floor. Push up through your front foot to return to the start position. Reps: 12 each leg Sets: 3 Rest: No rest, go straight into single leg bridge. How to do it: Place a bench or a box in front of you and step onto it with one foot.