The largest of the arthropods - coconut crab
Seeing this amazing arthropod, every nervous shudder with horror and surprise - in fact the world there is no one more interesting and at the same time more terrible than the coconut crab. In any case, among the arthropods - he is considered to be the largest of their representative.
At the coconut crab has many other "names": for example, a thief or a crab coconut crab - it's strange arthropod really steal your booty. The travelers of the past centuries, who visited the islands, which lie in the West Pacific and the Indian Ocean, they say that the coconut crab hidden from prying eyes in the thick foliage of palm trees to then suddenly grab their prey, which lies directly under a tree or near From him.
Coconut crab (lat. Birgus latro) actually crab is not at all, despite the striking similarities with the arthropod relatives mentioned in the title. This land hermit crab belonging to mind decapod.
Strictly speaking, be called palm thief land arthropods can also be a stretch as part of his life is spent in the sea element, and even to light tiny crustaceans appear in the water column. Newborn babies with vulnerable soft abdomen busily crawling on the bottom of the pond in search of a reliable house, which can serve as a nutshell, and deserted clamshell.
The "child" birgus latro not too different from a hermit crab: he drags behind him his shell and almost all his time in the water. But coming from one larval state and leaving the water, he is no longer able to go back there, and at some point and wearing of a shell-house. Unlike bryushek cancers recluse its abdomen is not Achilles heel and gradually hardens, and the tail curls under the body, protecting the body from cuts. Due to the special light, he begins to breathe out of water. In truth, most legends noted this is the feature - the first Europeans arrived on the island, described as the coconut crab hiding in the trees creatures with long claws, which are suddenly stretched to the ground and captures the prey, until the sheep and goats. Scientists have confirmed that birgus latro has great strength and can lift up to 30 kg of weight. However, they found that their ability to use the crab to drag the goods from place to place, preferring to feed on dead animals, crabs and fallen fruit.
Due to what is possible cancers exist equally comfortable in the water and on land? It turns out that the wise nature has provided them with two breathing tools: lightweight, ventilated air on the surface of the earth, and gills that allow to breathe underwater. That's just over time, the second body loses its function, and palm pilferers have to switch completely to terrestrial life.
I wish to meet a miracle would have to go to the tropics - coconut crabs are found on the islands of the Indian Ocean and some Western Pacific islands. To see them in the light of the day is not easy: palm thieves are nocturnal, and solar time hiding in rock crevices or burrows in the sand lined with coconut fiber - it helps to maintain the required level of humidity in the home.
And though the version that their front claws cancer is able to split a coconut, failed miserably, his limbs, however, sufficiently developed to quickly climb up the trunk of a palm tree or bite a person phalanx. And to coconuts cancer really indifferent: nourishing flesh - the main dish in its menu, which he owes his "coconut" name.
Sometimes crayfish diet enriched with fruits pandanov, and according to some sources, palm thieves happens and eat their own kind. Hungry cancer unerringly finds the closest "restaurant": internal navigation is a great sense of smell, which is and outputs it to a food source, even if it is many kilometers.
As for the "thieves' status as a" cancer, but this is guilty of his irresistible desire to pull into its burrow sundries from the category of that which is bad - edible and otherwise.
coconut crab meat, not only is among the delicacies, but also applies to aphrodisiacs, so these arthropods are actively hunting. To prevent their complete disappearance, in some countries there are strict limits on the catch coconut crabs.
The body of the coconut crab, like all decapods, divided into a front section (cephalothorax), which has 10 legs, and stomach. Front, the largest pair of legs has large claws (talons), the left claw much larger than the right. The next two pairs, like other hermits, great, powerful with sharp edges, use coconut crabs travel on vertical or inclined surfaces. The fourth pair of legs is much less than the first three, which allows young coconut crabs to settle in mollusk shells or coconut shells provide protection. Adults use this pair for walking and climbing. The latter, very little steam, which is usually hidden inside the carapace, females used for the care of the eggs, and the males - to mate.
With the exception of the larval stage, coconut crabs can not swim, and they will surely drown if will stay in the water for over an hour. Breathing they use a special organ called gill lungs. This body may be interpreted as a development stage between the gills and light, and is one of the most important adaptations coconut crab habitat. Gill tissue include lung, similar to that found in the gills, but suitable for the absorption of oxygen from air, instead of water.
Coconut crab is well-developed sense of smell, which he uses to search for food. Like most crabs live in the water, they have specialized organs located on the antennae that the concentration and direction of the odor.
During the day, these arthropods holed up in burrows or rock crevices that line of coconut fiber or foliage that would increase the humidity in the home. While relaxing in his burrow, the coconut crab closes the entrance of one claw to maintain a humid microclimate in the hole, which is necessary for his respiratory system.
As its name suggests, this crab eats coconuts, and actually be able to climb the coconut trees to a height of 6 meters, where the powerful claws pinch off coconuts, if they are not yet available on the ground. If a fallen coconut does not break if dropped, crab during the week, or even two will be his gut until you get to the juicy pulp of the nut. If this dreary job of work bored crab, he raises a coconut up a tree and throws it down, in order to facilitate their work. Going back to the ground, they sometimes fall, but without damage to health may suffer a drop of 4 to 5 meters. Do not give up the coconut crab and other fruits, the newborn turtles and fell. They also have been noticed for catching and eating a Polynesian rats.
Other its name - coconut crab, he has received for love of all that brilliant. If the path will fall crab spoon, fork, or other shiny object, rest assured, he will certainly try to drag him to his burrow.
Since the beginning of June to the end of August palm thieves begins the breeding season. The process of courtship is long and tedious, but the pairing itself is fairly fast. The fertilized egg is the female for several months in the lower side of the abdomen. When the eggs are ready for hatching, the female goes down to the sea at high tide and releases the larvae into the water. During the next three - four weeks floating in the water, the larvae go through several stages of development. After 25 - 30 days, have little crab sink to the bottom, settling in shells of gastropods, and are preparing to migrate to the ground. At this time, the kids sometimes visit dry land, and gradually losing the opportunity to breathe underwater, eventually moving to the main habitat. Coconut crabs reach sexual maturity after about five years after hatching, but reach their maximum size only to 40 years.
Palm thieves live in the tropics, on the islands of the Indian and western Pacific Oceans. Christmas Island in the Indian Ocean has the largest population density coconut crabs in the world.
The Swedish and Australian scientists have confirmed the veracity of the stories about the coconut crabs. Thus, the inhabitants of the Pacific Islands argued that those few kilometers can smell a smell, for example, meat or ripe fruit. Indeed, special bait, planted by the researchers, immediately attracted the attention of thieves crabs, which nevertheless disdained the usual slices of bread, for which the usual greedy crab.
The janitor is, of course, nice and helpful, however, as birgus latro being predominantly at night and not very friendly, stumbled on it, the locals do not feel much enthusiasm. Reduction of its population forced the local authorities to set a limit on the catch birgus latro. On Papua New Guinea may not include it in the restaurant menus, on the island of Saipan - catch crabs with a carapace of less than 3, 5 cm, and from June to September, during the breeding season.
On the inside surface of the wall in the gill cavities of land hermit crabs descendant acinar develop folds of skin, which ramify numerous blood vessels. This is - the real light, allowing oxygen to use gill filling the air cavity. Lungs are ventilated through skafognatita movements, and also because of the ability of animals from time to time to lift and lower the carapace, which is served by special muscles.
It is remarkable that at the same time preserved and gills, however, relatively small size. Removing the gills does not harm the breath; On the other hand, the cancer has completely lost the ability to breathe in water. Immersed in water coconut crab died after 4 hours. Residual gills apparently do not function. Coconut crab digs shallow burrows in the soil, which is lined with coconut fiber. Charles Darwin said that the natives on some islands is selected from palm thief nor the fiber they need in their nemudrenyh economy. Sometimes coconut crab content natural haven - crevices in the rocks, in cavities drained coral reefs, but also in such cases, their use for lining plant material, preserving housing high humidity.