Intelligent Design, the best explanation of Origins

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Intelligent Design, the best explanation of Origins » The catalog of life » The bola spider , which hunts by lassoing its prey

The bola spider , which hunts by lassoing its prey

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The amazing hunting techniques of the bolas spider

Creation surprises me almost daily with new discoveries, and evidences Gods brilliant creativity. To think that the millions of different creatures with their  uniqueness , each one with a different way of hunting, or defence mechanism, or camouflage or mimicry, hability of adaptation to the most variated environments and interdependence with plants and different kinds of animals, survival capability even in space like the tadigrades,  could have come into existence by any kind of mindless process is laughable and ridiculous to say the least.

The spider is shown to be an engineer of great skill and versatility. There are an estimated 100,000 species of spiders.

One more example is the bola spider, which has its name  from the argentenian lasso weapon

The common name ‘bolas spider’ is not particularly accurate, though. A real bolas – two or more weights connected by cord – is swung and thrown at an animal (like a horse, in the image below) in its entirety, and works by getting tangled around the legs of the target.

Bolas spiders are famous for their unusual and extraordinary prey capture technique: rather than a web, they produce a single silk line with a super-sticky ball of glue at the end, which they fling at their prey. instead of using a typical web to capture prey, they swing a droplet of adhesive, called bolas, on a thread at flying insects,  to capture moths. It works by getting stuck to the target, which is invariably a moth. Only male moths are captured. The flight behavior of approaching moths, the limited taxa caught from a large available moth fauna, and the fact that only males are caught support the hypothesis that the spider attracts its prey by producing chemicals, a scent which mimic the sex pheromones of these moth species. The bola spiders frequently capture more than one moth species on a given night. The spider could capture both species without producing different pheromone-mimicking compounds, simply by hunting during the activity period of each species.

Adult female bolas spiders have the incredible ability to produce a chemical cocktail that make them smell just like female moths advertising for mates (actually, no one knows yet which part of the spider’s body is responsible for this wonderful trick). Innocent male moths following what they perceive to be a pheromone trail (whose chemical message indicates that it leads to a sexually receptive female moth) are thus duped into coming in close enough for the spider to strike. This is called “aggressive chemical mimicry”, and it is awesome.

Moth sex pheromones are typically blends of two or more chemical compounds in very specific ratios. The particular chemicals and ratios allow male moths to discriminate between females of their own and other species. If a bolas spider produced just one moth pheromone, they  wouldn’t do very well, because their diet would be restricted to only a single moth species. It turns out that each species of bolas spider attracts several kinds of male moths.

More than 90% of their prey consists of two species in the family Noctuidae: the smoky tetanolita and the bristly cutworm . These two moth species produce entirely different sex pheromones, and they are active at different times of night. The problem for the bolas spider is that the bristly cutworm pheromone interferes with the attractiveness of the smoky tetanolita’s pheromone.

Here’s where the bolas spiders start to get really fancy. Let’s join an M. hutchinsoni female for a night of hunting, and learn some of her secrets.

She begins by building her horizontal “trapeze” line, from which she then hangs motionless, with front legs extended in hunting position (but with no bolas, yet). She is already emitting the sex pheromones (well, analogs that are close enough!) of both prey species, but so far, only the early-flying bristly cutworm is active. They aren’t put off by the smell of smoky tetanolita females mixed in with the pheromone of a female of their own species, and soon one is winging its way toward the seductive scent coming from the female spider. It passes close by, but out of reach. This moth is lucky, for now. But no matter; his fate is not our immediate concern. The spider’s outstretched legs are covered with tiny vibration-sensitive hairs (called trichobothria) that allow her to detect the sound of the moth’s wing beats nearby. Now that she knows there is prey about, she springs into action and spends the next minute or two building her sticky bolas.

Once her weapon is complete, she returns to her prey-capture position, with the bolas hanging from one of her outstretched front legs. For her next trick, she will again rely on her ability to detect the wingbeats of flying moths with her leg hairs. She waits patiently, silent and still.

Soon, another hapless male moth picks up the scent and starts winging towards the bolas spider. When her sensory hairs tell her the time is just right, she takes a swing at the approaching moth and connects. Although the moth struggles, shedding scales in its effort to escape, the wet stickiness of the bolas holds it fast. The spider reels the moth in and delivers a fatal venomous bite. She waits a few moments, then wraps her prize in swathes of silk and hangs it carefully from her trapeze line to eat later. The night is young, and the moths will continue flying for some hours yet. The bristly cutworms will remain active until 22:30. Our spider builds a fresh bolas, and settles in to wait. Gradually, the smell of bristly cutworm sex pheromone coming from the spider fades. The smell never disappears entirely, but is soon faint in comparison to the scent of a female smoky tetanolita. The smoky tetanolita males will come out after 23:00, and our spider will be ready for more deadly deception.

So far, we’ve discovered some of the adult female bolas spider’s secrets to success, but what about juveniles and males? They don’t use a bolas, but they are no less stealthy and deceitful than their counterparts. Young bolas spiders are also employ aggressive chemical mimicry to attract prey, but they specialize on male moth flies in the family Psychodidae. Each bolas spider species is especially attractive to a particular species of moth flies. It appears to be a pleasing coincidence that small bolas spiders prey on moth flies until they graduate to real moths. Whether or not the sex pheromones of the psychodids captured by each spider are similar to those of moths they specialize on is currently a mystery.

Optical illusions

Mastophora females are not only masters of chemical deception, but they are also visually cryptic, and hide in plain sight from their own potential predators. They do this by mimicking bird poop.

In order for their prey tactic be successful, several key features are necessary :

Bola spliders need :
-To produce a single silk line with a super-sticky ball of glue at the end.

Question: How did they " learn " to produce this kind of single silk and the ball at the end ? How did they learn to use it like a lasso to catch their prey ? Without the glue, the moths would not get trapped.

Silk line swinging : how did the spider learn to use the single silk line like a swinging  lasso ?

-Chemicals, a scent which mimic the sex pheromones of these moth species.
-Bolas spiders produce more than one moth pheromone to attract different moth species

Question : how did the Bolas spider " learn " to produce the right scent to mimic the pheromones of the moths in its nearby region ? and not only one, but two different moth pheromones ? How could evolution have evolved gradually these substances ? without the pheromones in place right from the start, there would be not enough moths around for a dinner.

-The problem for the bolas spider is that the bristly cutworm pheromone interferes with the attractiveness of the smoky tetanolita’s pheromone.

Question: how did evolution overcome this problem ? and why did it actually produce the substance to mimic the pheromone of two different moths, with different blends ?

-Tiny vibration-sensitive hairs (called trichobothria) that allow her to detect the sound of the moth’s wing beats nearby.

Question : hod did evolution evolve these hairs ? what good would they be for, if not in conjunction with the prey mechanism as a whole ?

-a fatal venomous bite.

Question : had the venom not have to be fully available since the beginning for the spider ? how otherwise could it digest the moth ?

-changes the smell of bristly cutworm sex pheromone to the  the scent of a female smoky tetanolita

Question : how did it learn that feat ?

-mimicking bird poop

Question : how and why did evolution supposedly evolve the mimics of poop ?  If it evolved it, it was in order to be able to camouflage for survival. If the camouflage was not there, would it not have been eaten by predators ?

Is the system not irreducible complex ? If the silk , the pheromones, the ability of lassoing, the vibration-sensitive hairs, the venom for digestion were not all together performing as a whole, there would be no Bola spider performing its awe inspiring hunting mechanism.

Is it not rational to conclude the amazing hability to catch prey of the Bolas spider is much better explained through the wisdom and amazing creativity of a powerful designer, rathern than random undirected natural forces without forsight ?

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