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by Berislav Horvatic » Tue Dec 19, 2017 11:00 pm
Ruggero Morimando wrote:Another thought of mine: black colour and cold climate. With H.viridiflavus it happens exactly the opposite: where I live in northern Italy black specimens are exceptions. In the hot and sunny Sicily they are the normality...
So, we are probably missing something?
What we are "missing" is the complexity of many interwoven factors. It just isn't that simple.
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Berislav Horvatic
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by Patrick Masius » Wed Dec 20, 2017 12:51 pm
Berislav Horvatic wrote:Paul Aiscan wrote:While most berus in the habitat I have observed are born brown and turn black over time, some are
born black aswell. Others (around a quarter) keep their brown color with the typical zigzag pattern.
That's a very interesting observation. I've always been told (by experts, no doubt) that no
melanisticadult V. berus had been born as such. Wrong experts, or just a lack of field data, or what?
The first published observation of freshly born melanistic
V. berus stems from the year 1852. Close to Greifswald (Germany) a regular coloured female gave birth to two black babies besides some normal ones. A second similar case was published by Hagen in 1886. These cases contributed decisively to the insight that melanistic adders do not represent a separate species (
Coluber prester), a belief that was still held in the first half of the 19th century.
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Patrick Masius
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by Berislav Horvatic » Wed Dec 20, 2017 8:16 pm
Well, freshly born totally melanistic V. berus - how many reliably observed in a century or two?
I've never seen a single one, but it's fair to admit, I also haven't seen a lot of V. berus juveniles -
of any coloration - they are so terribly secretive...
So, ask the experts, if any. I give up.
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Berislav Horvatic
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by Patrick Masius » Sun Jan 07, 2018 7:08 pm
You're right. These cases must be extremely rare exceptions.
About the degree of blackness: I'd need to check the publications again, but I think that it wasn t specified.
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Patrick Masius
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