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:
https://www.youtube.com/watch?v=d yYC5r8xMI.
(Report by Francis Mangubhai with help from Cheryl Haxen)
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