Monday, September 19, 2016

Wickedly Marvelous Spider Webs


 

Spiders are making a remarkable appearance in the garden this fall… there seems to be an immense population of them this year. Several new insights which have been the subject of rigorous research help in our understanding of this marvelous species.

Firstly, spider silk has long been considered one of the toughest known natural fibers and anyone who has ever watched an insect struggle to escape a web can attest to this. It is light and flexible and stronger by weight than high grade steel, making it perfect for hospital sutures and at the opposite end of the spectrum, military body armor.

However production of large quantities of spider silk has been a challenge. Scientists have been attempting to produce spider silk by genetically altering silk worms who mass produce silk for use in fabrics. *Their silk does not in any way have the strength of spider silk.  

Genetically altering the silk worm would allow for mass production of spider silk and the offspring of those silk worms would retain their new found ability to produce spider silk. Kim Thompson, CEO of Kraig Laboratories in Lansing Michigan, reports they have succeeded and are currently testing gloves made of spider silk. According to Thompson, ‘It’s a huge and sexy market’.  (Yes, that is a quote.)

Other news about spider webs was a bit more altruistic and uplifting.  In a recent article by George Dvorsky, he comments on studies conducted by  researchers in the United Kingdom and Spain who noted that spiders are capable of fine tuning their webs. Various signals are sent through the tension of a web, including the condition of the web and the presence of prey. The authors liken the web to a finely tuned guitar, as each strand of the intricate web transmits a vibration across several frequencies, allowing the spider, whose eyesight is minimal to ‘feel’ what is happening in his home.


The spider is also able to assess the environment, as each will collect the web and seek shelter if storms are approaching. Once over, the web will be quickly reassembled and life resumes as usual.

In my own observations, I have noted that the instant prey has accidentally flown or fallen into a web, the silent spider, resting quietly in the center of the web, will race as a streak of lightning to the exact spot, twisting and tumbling the poor victim into a cotton-like shroud, to be eaten then or saved for later as desert. Considering the strength of the web and the inhabitant dwelling within, it is small wonder we all dance the rapid hand-slapping, hair-jiggle-jarring jig when accidentally walking into a web on a fine Fall evening!

Monday, September 5, 2016

Spiders on the Move as Fruit Flies Abound




 

It becomes abundantly clear that Fall has arrived when quite suddenly the kitchen is loaded with tiny fruit flies. Appearing as out of thin air they hover about any piece of fruit in a small swarm... jiggling a ripe tomato will cause fruit fly panic.


They reproduce in a mere 8 days which is the reason that Gregor Johann Mendel used them in his scientific studies on biological features passed on through inheritance. Mendel noted that varying degrees of red in the eyes of fruit flies were directly passed to offspring and although his findings were largely over looked in 1885, further studies were conducted and by 1915 became the core of classical genetics. It is amazing that modern studies of DNA began with the humble fruit fly. 



Fruit flies are so small they may fly through a screen and they are beyond detection on fruits and vegetables picked outside or purchased at markets. They eat yeast produced by fermentation, the process that converts sugar to acids or alcohol which appears as fruit is beginning to spoil. The flies reproduce on the skin of these fermenting fruits or vegetables and suddenly you have a tiny swarm of adult fruit flies which will disappear as rapidly as they appeared as Fall progresses. 

 
With the advent of Fall spiders are on the move as well. Spiders are found in every corner of the planet, making them one of the most common invertebrates and they alone have eight legs. Spiders evolved about 400 million years ago, and were among the first species to live on land. All are predators which make them valuable to the gardener as they will eat flies, mosquitoes, grasshoppers, locusts, cockroaches, and aphids. Many live more than on season, with a gentle Tarantula in California living over fifty years in captivity.



There are many references to the spider in popular culture, folklore and symbolism. The spider symbolizes patience for its hunting with web traps, and mischief and malice for its poison and the slow death they cause their prey. Though not all spiders spin gossamer webs, spiders have been attributed by numerous cultures with the origin of basket-weaving, knot work, spinning, and net making. Lovely pottery artifacts featuring spiders may be found in all ancient cultures, so respect for them is universal.

 

Last week I found a gauze-like spider nest that had been hidden between the leaf of a Caladium. I had opened the leaf and kept vigil, watching the nest grow until dozens of teeny tiny baby spiderlings began to slowly emerge. The babies tentatively left the nest, each producing their first microscopic thread of silk as they moved about; they were fascinating!

The Fall garden  contains so much magic... observing the wonder of it will carry you through the rigors of winter.