Joshua Smith wrote:I've noticed some are suggesting that this population might be a result of escaped captive snakes crossbreeding. Seems unlikely to me, but my knowledge is limited and I'd be curious to see if anyone here finds merit in the theory.
Possible crossbreeding with some captive snakes? But what could be more probable of an ancient crossbreeding with ”some” aspis specimens, if the two species live together, in tight contact, and in an isolated environment?
And we must also think that the phenotypic differences of walser from berus point exacty in the direction of an "aspis morph": more fragmented and discontinuous zig zag pattern on the dorsum, and more fragmented and numerous head scales. Could it be simply a case? Or the walser is actually related to ursinii and kaznakovii?
Some genetic analysis suggest this “species” is in fact more related to ursinii and other species, which are very distant as regards their range: but what does it mean “related”?
We can read in the pubblication: “The adder from Piemonte appears more closely related to the cluster regrouping V. dinniki, V. kaznakovi (from Georgia) and V. darevskii even if the bootstrap support is limited. It is thus likely that the split between V. ursinii, V. darevskii–V. kaznakovi and the adder from the Piemonte occurred during a similar period.”
Ok: the adder from Piemonte (V.walser) has arisen from a not better specified ancestor viper group “in the same period” of ursinii, darevskii and kaznakovii.
But “in the same period” also many other vipers and many other snakes had arisen in the world: this does not mean that V.walser is related to Trimeresurus (even if they probably share the most of their DNA, if it’s true that our DNA is at 98,5% identical to the one of the chimpanzees!)
And the authors, in fact, specify: “even if the bootstrap support is limited”.
This is my point of view: are we really 100% sure that DNA, alleles and so on are so trustworthy?
I fear a lot, for instance, to submit myself to a DNA analysis: I would not read in an issue that my alleles are more related to those of an Australopithecus than to the ones of Brad Pitt…
Yes, I admit I’m a bit skeptical about DNA… And, besides this, the phenotypic differences of the human beings in the world are much more relevant, I would say in a huge way, than those between berus and walser: but nobody thinks to analyse the DNA of a black man and compare it with the DNA of a man from Japan, and maybe split the human race…
But let’s go back to our vipers.
We read: “Additionally, two nuclear protein-coding loci (BTB and CNC homology 1 – BACH1; Townsend et al. 2008 and recombination activating gene 1 – RAG1; Townsend et al. 2004) were used to investigate the genetic variability within the nuclear genome. PCRs and sequencing were conducted with the same protocol as for the mtDNA, with, respectively, the 6primers F_Nik_Bach1 and R1_Bach1 (St€umpel 2012), and the primers Rag1_F1 and Rag1_R1 (St€umpel 2012), and the PCR amplification cycles following St€umpel (2012). For this aspect, four individuals were investigated: one individual from Piemonte and one sample each of the following species: V. berus, V. a. francisciredi and V. a. ammodytes.”
Four individuals...
I’m not a statistician, but just 4 samples seem to me very few, to say the least…
But, I repeat, I’m not a statistician and I’m not a geneticist (even if I’m a medicine doctor). And so I cannot debate in the right way the problem or support what I feel, because I know and understand too little of alleles, DNA, mitochondria and reliability of the samples. This is impossible for me to say something more about the question, just as it’s impossible for me to say something about the neutrino, the quarks or the physics of the universe.
I can only admit, I’m not fully convinced of the importance of these genetic studies, particularly if they are born just to confirm the existence and the validity of a new “species”.
I only fear, with genes and DNA one could prove everything, and the contrary of everything.
Please take this post of mine just as a kind of joke or a provocating starting point for other thoughts and discussions!
