A demonstration of evolution in action
The cicadas of their various species are insects from the family of the fleas, which also includes bedbugs and aphids, and there is no connection between them and locusts. The young cicadas, called nymphs, live in the soil and most of their species feed on tree roots. When they reach maturity, they come out of the ground, mate, lay eggs on the trees and die. The nymphs that hatch from the eggs fall to the ground and burrow into it, and thus their life cycle begins anew.
A certain species of cicada that lives on the east coast of the USA, is gaining publicity these days (May 2004), because of the huge amounts of adult insects that occupy large areas, because of the strong chirping that the masses of insects (the males - to attract the females) make and especially because of the fact That this only happens once every 17 years. During the rest of the year, the same cicadas live in the soil. These cicadas are characterized by a life cycle of 17 years - unlike most species of cicadas whose life cycle is annual, such as the cicada species found in Israel and many other places - including the USA.
The question arises, why do these cicadas spend their childhood phase, so many years in the ground and why exactly 17 years?
If such a long life cycle is not an amazing enough fact, then another amazing fact is that two more species of cicadas with a multi-year life cycle are known - one in which the life cycle is also 17 years (which may have developed independently and separately from the famous cicadas of the eastern USA) b) And another species whose life cycle is 13 years.
What is special about the numbers 13 and 17 that different species of cicadas have chosen such numbers of years, as the length of their life cycle?
The answer is that these two numbers are prime - and not so small (smaller are 11, 7, 5, etc.)
But this does not yet explain why the cicadas developed such a life cycle during their evolution.
The answer to this question is related to one of the mechanisms of evolution, which is the incessant evolutionary race between a predator and its prey.
An example of such an evolutionary race is the speed of the jaguar and the deer that serves as its prey. During evolution, each of the species developed speed - the fast jaguars got more food and the fast deer were eaten less. Evolution favored speed and over the generations the running speed of both sexes increased.
In the case of the cicadas, the evolutionary race between them and their predator was expressed in the adjustment of the life cycle - so that the cicadas are available as food exactly when the predator needs it.
So every year in the spring, when the cicadas rose from the ground, their predator was waiting for them. It is possible that their predator was also a species of insect that fed on them directly or that laid its eggs in their bodies.
It is possible that the predator was so common that it put the existence of the species of those cicadas in danger and then the cicadas that happened to have a two-year life cycle, had a better chance of survival.
For a predator, two solutions in such a case. Or he also has a species that maintains a life cycle of two years, or he is able to survive in the format of a year of abundance and a year of scarcity.
The race continues with the emergence of species with longer life cycles than the cicadas and the predators may also develop suitable life cycles. The hemlocks help the predators. For example, if a species of cicadas developed with a life cycle of six years, there could be carnivores that developed an identical life cycle, or a life cycle of two or three years and then they had one cycle of abundance in food and one cycle (or two) of limited food in which they satisfied themselves with the species others of prey, including possibly "normal" cicadas with an annual life cycle.
From this it is clear the advantage for cicadas, of a life cycle with a long number of years which is a prime number, so that the predators cannot take advantage of the multiplication of even numbers or divisible by three, etc.
This also explains the huge number of cicadas of a species with a long life cycle, which have no obvious predators, compared to a relatively small number of cicadas of a species with an annual life cycle.
It can be said that the cicadas of 17 and 13 years won the evolutionary race, in that their numbers are relatively large, because they do not have many predators. Those predators that tried to infect the cicadas with life cycles with a large and initial number of years - did not succeed and became extinct.
The mechanism by which the cicadas count the years is not known. It is clear that this is an internal mechanism and not something that relies on external cues, such as seasons, hours of the day, sunlight, temperature, etc. as exists in many cases in the animal and plant world, when it comes to daily or seasonal cycles. There is nothing in the living environment on Earth that has a 17 or 13 year cycle.
And after the cicadas finish laying their eggs and die, we can wait until the spring of 2021, when the new generation of adult cicadas will flood the eastern United States.
After 17 years, billions of noisy cicadas have once again taken over the US East Coast
17/5/2004
Washington. They started appearing last week, slowly crawling out of small holes near the tree trunks and starting to spread their wings. A few eyewitnesses who noticed the full-grown insects were enough to declare the "summer of the cicadas" - a phenomenon that occurs once every 17 years. Billions of cicadas suddenly emerge from the ground and take over the central east coast of the USA, in enormous density and with deafening noise.
The North American cicada has an unusual life cycle. Most of her life is underground, where she eagerly sucks the roots of trees. Once every 17 years the cicada's mating season arrives and then it digs a tunnel for it, goes above ground and begins a vigorous journey to find a mate. The courtship method of the cicadas is especially disturbing, at least to the humans living around. The males make a loud chirping noise that should convince the females to choose them for mating.
The noise made by a single cicada reaches 90 decibels, and since it is a concentration of thousands of cicadas per square kilometer, the noise in the entire area becomes unbearable. This type of large cicadas is typical only for the northeastern USA, between New York in the north and Georgia in the south. The most intense cicada activity is in the Washington area and the mid-Atlantic states.
Although the cicada attack is just beginning, the hysteria in the affected areas is already at its peak. In stores for building supplies, the stock of "cicada nets", which are supposed to protect the vegetation and the houses from the thousands of flying insects, sold out within hours; Nimble entrepreneurs offer for sale t-shirts with cicada drawings and kindergartens boast small "cicada corners" where you can follow the life course of the insects. Already now, walking on the sidewalks in certain parts of the city has become an unpleasant experience, fearing that every step will bring with it a crushed cicada under the sole.
There are also those who eagerly await the cicadas - entomologists who take advantage of the rare opportunity to learn about the unique life cycle of the cicada, small children who believe that it is some kind of pet and even some eccentrics who have already declared that they eat cicadas and that it is a delicacy.
Why do the cicadas come out en masse once every 17 years? Entomologists estimate that the mass invasion is intended to maintain the continuity of the species. The cicada is a rather vulnerable creature - its clumsy behavior and minimal intelligence make it easy prey for birds and pets, and humans do not take kindly to it either, because of its repulsive appearance, its disturbing chirping and its inconsiderate invasion of their lives. The secret of conservation is in quantity - even if thousands of cicadas are eaten, there will still be billions of them to continue the breed.
The cicada attack will reach its peak in the next two weeks and will only end in a month, when the cicadas will mate, lay eggs and die. Residents who remember the previous summer of cicadas, in 1987, say that when the attack ends, silence reigns, after long days of deafening noise, and the thousands of cicadas that filled the air, disappear in favor of sidewalks, roads and gardens covered with the insects' corpses. Until the cicadas appear again, in 2021.
Natan Gutman wrote "Haaretz" in the USA
Billions of cicadas will invade the US in May
The cicada, a buzzing insect that resembles a locust, emerges noisily above the face of the earth every 17 years exactly. The insects, which usually mate and die a few weeks later, are expected to "attack" the east coast of the USA
Wow news
3/4/04
Americans from the East Coast planning to have a wedding in May are advised not to hold the party outside. Billions of buzzing cicadas prepare to invade the area after 17 years of living underground.
The insects, known as "periodic cicadas", emerge noisily above the surface of the earth every 17 years, mate like crazy and die a few weeks later. American settlers in previous centuries mistakenly thought cicadas were locusts. Cicadas are distinguished from locusts by their pearly red eyes, but their most striking feature is the deafening, drumming-like noise the males make to attract females.
Many residents from North Georgia to Washington, D.C. fear the appearance of the noisy insects in mid-May. The entomologists, on the other hand, are counting the days until the event. "We don't see cicadas as a nuisance. On the contrary, the fact that they appear is a sign that humans have not destroyed their natural environment," said Gary Howell, an entomologist at the Smithsonian Institution's Museum of Nature.
Howell advises residents to look forward to the arrival of the insect swarm and to listen to the male chorus. Three species of cicadas are expected to emerge from the ground, and according to Howell, each species makes a noise at different times, almost like shifts. However, most male cicadas are silent at night.
AdvertisementResearchers are trying to understand how the cicadas know when is the right time to emerge from the soil, where they feed on tree roots. "We still don't know how they count the years. There may be environmental cues that help them," said Chris Simon, an ecologist and evolutionary biologist at the University of Connecticut.
The cicadas usually emerge at night when the ground temperature is about 18 degrees Celsius, and climb trees and fences. They hatch, mate and lay eggs. Simon recommends that people go out with flashlights and watch the cicadas as they emerge from the ground and are white in color. After that, their body becomes dark and the body sheath hardens. "You can hear them walking among the leaves, and if you shine a flashlight on the trees, you can see that they are full of white cicadas. It's an amazing sight," said Simon.
The flying attack
The east coast of the USA is covered in clouds of locust-like insects. And the Americans - celebrate and eat
Miriam Fox, New York
The US East Coast is under attack. Not the terrorist attack for which they have been preparing for two years, but a cicada attack - an insect the size of a grasshopper that makes loud chirping noises when it rubs its wings.
It started this week. Several researchers have already seen the cicadas starting to come out of the ground. After 17 years of hibernation, billions of insects have awakened, and soon they are expected to fly like locusts on the east coast of the USA, from North Georgia to Washington.
The clouds of cicadas will be accompanied by a loud noise, landing on trees, disturbing the pedestrians and causing a noise similar in intensity to a lawnmower. All this will continue until they finish the crazy mating ritual, around June, and die.
Hoping that nature will have its way, they will wake up in 17 years, after a long hibernation, and the new larvae, the fruit of this year's celebration, will go on their own mating orgy.
The cicadas are black insects about four centimeters in size, with transparent wings and red eyes, and they are harmless and do not sting. Their whole ambition in life is to be able to climb out of the holes in the ground into the open air and stay there for two weeks, just to find a son or a mate and reproduce before they die.
According to Michael Raup, a professor of entomology at the University of Maryland, the courtship customs of cicadas are very similar to those of humans.
In the first stage, the male plays to the female the melody built into the language of the cicadas, "How are you?" After her he is interested and asks "Do you come here often?", but only in the third stage of the courtship song does he finish the deal and ask the bewitched cicada "That's it, the bar is closing. Do you want to come to my house?"
Only then do the billions of cicadas break out in the dance of love. They settle in the yards of the houses and on the tops of the trees, and in their sex orgy they make a deafening noise. The noise produced by one cicada can reach 90 decibels, so imagine the noise produced by billions of insects.
A healthy substitute for a hamburger
According to scientists, the cicadas are only found on the eastern side of the US. They prefer to live at the edges of the forests, where the trees are young and less dense. They live in the darkness of burrows, which sometimes reach a depth of over two meters and suckle their food from the roots of young trees. At the end of the 17 years they crawl up the roots of the trees towards the air of the world, shed their bark and go out dancing.
Residents looking for ways to get rid of cicadas will find there are very few. "Soon we will receive phone calls from residents who want to know how to get rid of them," Greg O'Neill, an expert in tree care from the town of Princeton in New Jersey, told the New York Times, "There is nothing to do about them, except to wait for everything to pass."
The experts say that there is no danger to humans or animals, but damage can be caused to trees or bushes. Do-it-yourself stores have long since run out of special nets that can be used to view the bushes in the yard.
But not everyone plans to lock themselves in their homes. Entomologists only get to experience this celebration three times in their professional lives, and they are not going to miss this opportunity.
That's why Raup and his students are organizing for this special event, and until the cicadas attack, they attack the disturbed public with a sedation attack and even released a cookbook with cicada recipes.
odd? Not everyone thinks so, and some even think that the cicadas are a healthy substitute for a hamburger. According to biologist Gene Krinsky, "cicadas are nutritious and a source of vitamins." In addition, he claims that they taste like asparagus, especially if eaten uncooked or steamed.
Shake, do not mix
If you're planning to visit New York during the bug attack, there are a few caveats to keep in mind before you take a bite. Of course, a doctor should be consulted, since as with any other food, some people can develop an allergic reaction to these delicacies.
One should be careful about eating cicadas that come from areas where chemical substances are used as pesticides, since they can absorb these pesticides in their bodies.
The sequel is intended for those who are ready to sink their teeth into the cicada meat. Well, the best cicadas are the ones that just crawled out of the burrow and immediately shed their hard shell. It is good to collect these early in the morning even before they have enough time to climb to the tops of the trees.
Those who find it difficult to get up in the morning will have to make do with females. These have big, soft bellies full of nutritious eggs. The males, on the other hand, are not fit to eat, because their bellies are small and hollow and it serves as a resonating device that allows them to sing the love song in a loud and shrill voice.
The stew can be made in all kinds of ways, as the chef imagines, but most people prefer to grill them, so they get a nutty flavor, and dip them in the sauce.
White and red wine are not suitable for cicada dishes, claims the bartender of the Ritz Hotel in Washington DC. This month he prepared a drink called the "cicada cocktail" consisting of cold vodka, fresh pineapple juice with a drop of blue Curacao. The cocktail should be served in a martini glass, stirred, not stirred.
For information on the Daily Local website
