The scorpion: a light in the dark night

(8 Dec 2017) Contrary to crocs, snakes and sharks, Australian scorpions don’t belong to the category of “extraordinary dangerous”. But they have another remarkable feature: they light up in the dark under a ray of UV light.
And it is persistent: fluorescing even happens with million years old scorpion fossils. Night walkers use UV light to find scorpions, which leaves the question what other purpose the fluorescence might serve. The best answers are only guesses: it could protect them from sunlight, if might help in finding each other or they might confuse prey. The blue-green glow comes from a substance found in the hyaline layer, a very thin but super tough coating in a part of the scorpion’s exoskeleton, the hard outside cover of the insect. Hyaline is a byproduct of the hardening process itself and survives the fossilizing process.
Scorpions are nocturnal hunters, feeding mainly on beetles, cockroaches, spiders, centipedes and millipedes. The main predators of scorpions are carnivorous marsupials, rodents, lizards, nocturnal birds, centipedes and other scorpions. Scorpions are closely related to spiders, ticks and mites.
Males and females find each other by vibration, scent and touch. During mating, the male deposits his spermatophore. Then the male and female perform a mating dance, with the female being wrestled into position over the clump of sperm in order to draw it up into her genital pore. She gives birth to live young, even carrying the young scorpions on her back for the first few days. Most will live for many years, some up to 25 years.
Australian scorpions can give a painful sting which can cause inflammation and pain for several hours. First aid for a sting is to apply a cold pack and to seek medical aid if pain persists.

Technique
Top photo: f/15, 1/20, ISO 60, flash. A photo taken with a full automatic Nikon camera in April 2006.
The second photo was taken this year with a much more sophisticated Canon EOS 700D, flash, f/10, 1/120, ISO 800.
The difference is not that remarkable. Automatic camera’s clearly can still do a very good job.