Mimicry

There are various forms of mimicry. Some of the best-known protostomes that engage in mimicry are butterflies. The species Zeltus amasa maximianus (Lycaendae) increases its chances of surviving an attack by giving its enemy a choice of two heads—one of which is a decoy. By presenting a predator with a convincing false target, the probability of surviving an attack is increased. The decoy, or "false head," is created by morphological adaptations present on the wing

Sea Cucumber Cure For Diabitas
A toxic nudibranch (Phyllidia coelestis) and juvenile sea cucumber (Bohadschia graeffei), both displaying aposematic or warning coloration. (Photo by A. Flowers & L. Newman. Reproduced by permission.)

tips. False-head mimicry requires not only morphological adaptations, but also that the animal be able to engage in behavioral patterns that will focus a predator's attention on the decoy. One of the methods a butterfly might use to focus a predator's attention on their false head is to make their morphological adaptations seems more "attractive"; this process is accomplished by certain butterflies using the ribbon-like structures located near their wing tips. When the butterfly moves its wings the ribbons begin to resemble antennae, diverting attention away from the true head located on the opposite side of the butterfly.

A similar strategy is also common in caterpillars. In species of Lirimiris (Notodontidae), the animal actually inflates a head-like sac at its rear. The resulting fictitious appendage draws the attention of the predator away from the actual head to the comparatively tough rear end. Another version of the false head is found in crab spiders (Phrynarachne sp.), and longhorn beetles (Aethomerus sp.), whose mimicry resembles bird feces, and the Anaea butterfly caterpillar (Nymphalidae) that resembles dried leaf tips.

In contrast to false mimicry, some protostomes actually mimic the behavior of other species. Active mimicry is common in a wide range of invertebrates. An interesting example is found in Acyphoderessexualis (Ceramybiid). This beetle mimics the behavior of two different animals, depending on the threat. When the beetle is touched, it resembles some species of ponerine ants (Formicidae), and when threatened in flight, the behavior changes to resemble polybiine wasps. Another example is tephritid flies (Rhagoletis zephyria). At least two genera emit behaviors that resemble salticid spiders—their main predator. Many other fascinating examples can be found, including wasps (Ropalidia sp.) that create nests resembling fruit, and assassin bugs (Hiranetis braconiformis) that reduce the probability of serving as a parasitic host by imitating the walking pattern of its impregnator, complete with fake ovipositor.

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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