Thursday, September 3, 2015

Report on August Speaker

August is the month of the AGM of the Toowoomba Field Naturalists Club and the speaker for the meeting is selected from among the members. On this occasion the speaker was Cheryl Haxen, ably supported by Philip at the computer. Their talk was entitled ‘Leonardo da Vinci – Designs of art and nature’.
Flying machine
Cheryl and Philip had visited the Museo Leonardo da Vinci Firenze which displayed works constructed out of the designs found in da Vinci’s many notebooks. These designs, constructed into reality using wood, showed weapons, including a work that we would now term as ‘a weapon of mass destruction’ because it was a circular enclosure that allowed firing in all directions at the same time. Another weapon was four scythes set on a rotating shaft – four times as much carnage as one scythe could inflict. As Cheryl explained, it was ironic that da Vinci had so many diagrams dealing with making warfare more bloody when he had, at one stage, professed to be against war. But there were other designs also: including an odometer, a pedal-operated paddleboat and a flying machine that was no different from our modern ‘hang glider’.

Maratus jactans
 Cheryl then went on to show the genius of nature and talked about and showed slides of the peacock spiders, e.g. Maratus volans which is a species in the jumping spider family, belonging to the peacock spider genus. The male spiders put on a performance for the female which includes displaying their coloured flap-like extensions of their abdomen. These spiders are only about 5 mm in body length and can be found in parts of Queensland, New South Wales, Western Australia and Tasmania. The names of Jurgen Otto and David Hill are associated with these species.
      1. Maratus splendens. Collected in 1896 by the aptly named W.J.Rainbow,
it was only re -discovered by Jurgen Otto in 2011 near Sydney.
2. Maratus personatus. Recently discovered Blueface.  Female of the blueface. Most females of peacock spiders are similar to thisi.e. lacking display colours.
         3. Maratus elephans. Recently named for the elephant design on his abdomen.
Maratus skeletus
        4. Maratus jactans. Along with the next species discovered only this year at Wondul Range National Park not far from Toowoomba by Berkeley student Madeleine Girard and Australian Eddie Aloise King. Madeleine dubbed this'sparklemuffin' for its flashy displays which include inflation of the spinnerets.  
     5. Maratus skeletus which Madeleine termed 'skeletorus' for its skeletal markings.
     Cheryl mentioned that Youtube films of these spiders are available and given below is a link to one such film: 


      (Report by Francis Mangubhai with help from Cheryl Haxen)

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