Peer Review #2 of "The adder (Vipera berus) in Southern Altay Mountains: population characteristics, distribution, morphology and phylogenetic position (v0.1)"

As the most widely distributed snake in Eurasia, the adder (Vipera berus) has been extensively investigated in Europe but poorly understood in Asia. The Southern Altay Mountains represent the adder’s southern distribution limit in Central Asia, whereas its population status has never been assessed. We conducted, for the first time, field surveys for the adder at two areas of Southern Altay Mountains using a combination of line transects and random searches. We also described the morphological characteristics of the collected specimens and conducted analyses of external morphology and molecular phylogeny. The results showed that the adder distributed in both survey sites and we recorded a total of 34 sightings. In Kanas river valley, the estimated encounter rate over a total of 137 km transects was 0.15 ± 0.05 sightings/km. The occurrence of melanism was only 17%. The small size was typical for the adders in Southern Altay Mountains in contrast to other geographic populations of the nominate subspecies. A phylogenetic tree obtained by Bayesian Inference based on DNA sequences of the mitochondrial cytochromeb(1,023 bp) grouped them within the Northern clade of the species but failed to separate them from the subspeciesV. b. sachalinensis. Our discovery extends the distribution range ofV. berusand provides a basis for further researches. We discuss the hypothesis that the adder expands its distribution border to the southwest along the mountains’ elevation gradient, but the population abundance declines gradually due to a drying climate.

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Peer Review #2 of "A new species of the archaic primate Zanycteris from the late Paleocene of western Colorado and the phylogenetic position of the family Picrodontidae (v0.1)"

10.7287/peerj.191v0.1/reviews/2 ◽

2013 ◽

Author(s):

M Silcox

Keyword(s):

New Species ◽

Peer Review ◽

Phylogenetic Position ◽

Late Paleocene ◽

Western Colorado ◽

The Family ◽

A New Species

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Population characteristics of the adder (Vipera berus berus) in the Northern Romanian Carpathians with emphasis on colour polymorphism: is melanism always adaptive in vipers?

Animal Biology ◽

10.1163/157075511x597601 ◽

2011 ◽

Vol 61 (4) ◽

pp. 457-468 ◽

Cited By ~ 6

Author(s):

Alexandru Strugariu ◽

Ştefan R. Zamfirescu

Keyword(s):

Body Size ◽

Model Organism ◽

Short Review ◽

The Body ◽

Population Characteristics ◽

Colour Polymorphism ◽

Vipera Berus ◽

Adaptive Processes ◽

Romanian Carpathians ◽

The Subject

AbstractThe adaptive significance of melanism and the hypotheses regarding the maintenance of colour polymorphism in snake populations have been the subject of numerous studies and great controversies over the years. The present paper aims to present the first data on population characteristics of the adder (Vipera berus berus – one of the taxa most frequently used as model organism in studies on colour polymorphism) from the Carpathian Mountains, with emphasis on the frequency of melanistic individuals and comparison of body size between the two morphs. A short review of the frequency of melanistic individuals in populations described by previous studies is also presented. Given the fact that melanistic individuals were infrequent in this population, that no significant differences were detected with regards to the body size of the two morphs, and the supporting literature, we conclude that maintenance of colour polymorphism in this population might result from non-adaptive processes, having no or very little adaptive value.

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