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A study of striped color patterns and of the striped/non-striped polymorphism system in snakes reveals that the stripped pattern is mostly found in the family Colubridae. The stripped pattern indicates that the Colubridae adopts an active escape behavior strategy. The striped/non-striped polymorphism of the snakes depend on the type of the habitat. The striped morph is present in snakes with active escape behavior that requires camouflage. The non-striped feature is dominant in snakes which require the process of thermoregulation for physiological purposes.

Eye size is interesting in snakes because in most species body length differs between the sexes, while the eye's performance depends on its absolute size. So, does the smaller sex see less well? We hypothesized that eye sexual mensural dimorphism (SMD) would be smaller than Body SMD. We found among 26 snake populations that body length SMD was female biased in 47.6% and male biased in 38.1% of samples. Often the larger sex's head was further enlarged but the SMD of absolute eye size was mitigated or annulled by the smaller sex's eye being enlarged within the head, and the head enlarged relative to the body. Overall generally the SMD of eye size was smaller than body SMD. This accords with a hypothesis that eye size affects the evolution of head size and its SMD, both reflecting and emphasizing that absolute eye size is functionally important. Although Colubridae exceed Viperidae in length, Viperidae have larger eyes in absolute terms. In Colubridae the females have larger eyes and in Viperidae the males have larger eyes. Additionally we examine to what extent SMD in different characters is correlated, and briefly review other aspects of SMD, including some aspects of Rensch's rule. [ABSTRACT FROM AUTHOR]

Widely accepted major criteria for biodiversity hotspots that deserve conservation include species richness, endemism and threat. Proving that a taxon is endemic to a given area is more difficult, and therefore expensive, with animals than with plants because of the difficulty to prove absence outside the known distribution. Seeking a cost-efficient practical method to show animal endemism while funds necessary for conventional demonstration of endemism are lacking, we argued that when the known distribution of a suspected endemic taxon coincides with an eco-geographically isolated area, e.g. island, its exclusivity to that area is more credible. We selected a model site containing suspected endemics, the ‘Arava depression (altitude - 400–0 m) between arid southern Israel and southern Jordan. A search of the literature and collections found at least 23 animal taxa endemic to the ‘Arava, to the adjacent Dead Sea basin sharing the depression, or to both. We assessed the level of isolation of the ‘Arava depression by statistically analysing the geographical distribution of taxa (species or subspecies) of one selected well researched model group, Squamata (lizards and snakes). In northern Israel and Jordan the squamate faunas of the two countries are very similar. In contrast in the south where the ‘Arava intervenes, the two faunas greatly differ. The ‘Arava both constitutes a partial barrier and is partly isolated. Hence its apparent endemics are likely real endemics, inviting conservation of the area. The more so since the ‘Arava is also an arena of much research and education. Our methodology may serve worldwide to identify semi-isolated terrestrial areas for conservation. [ABSTRACT FROM PUBLISHER]

The geographical distribution of reptiles is known to be climate dependent. Our analysis of literature data from the Palearctic confirmed that snakes, as a group (186 species), tend to extend further to the north, into cooler climate, than lizards (460 species). This has also been reported for the Nearctic. On a smaller scale, as a model, we investigated the expansion of reptiles from the warm southern desert of Israel northwards along the Jordan valley into cooler climate, based on 587 locality records of 17 species. It transpired that the snakes significantly extend further to the north than the lizards, paralleling and exemplifying the global scale. The ability of snakes to inhabit relatively cooler climates appears to accord with three physiological traits of snakes: lower optimal body temperatures, absence of temperature-dependent sex determination, and ability to thrive on infrequent meals. [ABSTRACT FROM AUTHOR]

Body size is an ecologically important variable in animals. The geographical size variation of most snakes and some lizards counters Bergmann's rule in that, among related taxa, the larger ones live at warmer latitudes. However, exceptions notwithstanding, and despite being ectothermic, turtles as a group tend to obey Bergmann's rule. We examined this idea in Testudo graeca, ranging from Morocco to Romania and to Iran with disputed systematics, both at the global scale (using literature) and within the focal area of Israel (using museum specimens). Both globally and locally, carapace length correlated with latitude, in accordance with Bergmann's rule. The scant data on reproduction fully support the hypothesis that Bergmann's rule enables larger clutches where the climate would limit repeated clutches. The sexual size dimorphism ( SSD) was approached using two methodologies: (1) 'conventional', using globally literature data and locally museum samples and (2) 'innovated', using photographs of copulating tortoises from Israel and Turkey. By each methodology, SSD emerged as being male biased in the larger-bodied populations and female biased in the smaller-bodied populations, obeying Rensch's rule. Some observations support the hypothesis that the evolution of large males serves intermale combating. Finally, Rensch's rule was found to apply separately within Anatolia and within the Levant, possibly indicating that these populations are separate. [ABSTRACT FROM AUTHOR]

The article evaluates the allocation of the Arabian desert lizard in the Levant, Jordan. The lizard at the Levant was studied in terms of its physical appearance based on the specimen found in 1980, where it was compared to the ordinary Acanthodactylus (A) opheodurus lizard in terms of the vertebral dark stripe. Results showed that the Arabian desert lizard species differ in terms of colour patterns, where A. opheodorus has a vertebral dark stripe while A. boskianus has a forked stripe.

The publication entitled Description de l'Égypte, which carries scientific results from Napoleon Bonaparte's conquest of Egypt, includes illustrated descriptions of two lizards, Acanthodactylus boskianus (Daudin 1802), and the new A. asper (Audouin 1827). We note that their original drawings differ conspicuously in the degree of abruptness with which the dorsal scales are enlarged towards the rear of the back. However, this character has been overlooked by later researchers, who often found it difficult to distinguish the two nominal species by conventional transverse scale counts. We developed a method to quantify the degree of abruptness with which scale size changes along the back. For studying this new descriptor we reduced the expected within-sample variation by limiting the sample in two ways: (1) viewing the sexes separately, and (2) heeding the Seligmann effect and considering only whole-tailed individuals. However, the systematic problem persisted. According to our graphic analysis, in A. b. asper both the degree of abruptness of change in scale size, and when abrupt, the location of this change along the back, varied strongly but unimodally. The ranges overlap between provisional geographical areas. Similar abruptness in the change of dorsal scale size does not occur in the populations called A. b. boskianus and A. b. euphraticus. We conclude that the two classical illustrations must be considered as representing two extremes of a complex gradient. The taxonomic implication is to maintain the current trinomials in the complex until a major revision may direct otherwise. [ABSTRACT FROM AUTHOR]

Recent arguments in the literature prompted us to compare methods for assessing sexual dimorphism in body proportions of lacertid lizards, using Acanthodactylus boskianus. Although expressing body-part measurements as proportional to head length was the most effective method, we recommend using trunk length for the baseline as a general method for lizards. We also argue that, when aiming to assess sexual dimorphism in body proportions of lizards, if the context is ecological, all available adults should be included. However, for morphology and taxonomy, small sub-samples of the largest individuals that maximally express their genetic morphological potential should be used. In A. boskianus, the sexual dimorphism of mensural characters in adults was typical: males were larger, with relatively larger head and appendages. However, the ontogeny of this dimorphism was unusual in that the differences existed already in youth and thereafter persisted isometrically. The sexual dimorphism of meristic characters was male-biased in numbers of femoral pores and of caudal vertebrae, and female-biased in numbers of ventral plates along the trunk and of precaudal vertebrae. Size dimorphism may conceivably play a role in sex recognition because two potential visual cues (i.e. size dimorphism and dichromatism) appear to complement each other. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society 2009, 97, 275–288. [ABSTRACT FROM AUTHOR]

Based on nine calls of Calodactylodes illingworthorum recorded in the wild in Sri Lanka, the 'spontaneous' call of the species is a very rapid series of 4-7 roughly similar chirps. Call parameters are compared to those of Ptyodactylus guttatus of Israel because the species are similar in morphology (size, proportions, digit shape, scutellation, coloration), ecology (rupicolous, nocturnal), and reproductive biology (clutches of two eggs, stuck to rock, in 'rookeries'). The calls of the two species, despite similarity in basic structure, greatly differ in the number of chirps, chirp repetition rate, total duration, dominant frequency, and relative intensity level. The functional implications of these differences are briefly considered. [ABSTRACT FROM AUTHOR]

Tail autotomy and regeneration are less known in Sphenodon (‘Reptilia’: Rhynchocephalia) than in Squamata. We examined museum specimens, Sphenodon guntheri ( N = 8) and Sphenodon punctatus ( N = 172), wild Sphenodon punctatus ( N = 19) and Sphenodon sp. skeletons ( N = 8). In S. punctatus, unlike in typical Squamata, sexes had similar relative (intact) tail lengths, and regeneration frequencies; tail and body growth was isometric. Tail breakage was usually intravertebral, usually followed by ablation of a variably sized terminal vertebral piece, partly deviating from lizards. Hypothetically, imperfect autotomy results from sphenodon's primitiveness. As in squamates, tail-losers were morphologically more left-side dominant than tail-retainers. Individual directional asymmetries in digit morphology and in digit injury were correlated (in lizards observed only at population level); tail-losers had more fluctuating asymmetry but their exclusion did not facilitate morphological taxonomic distinctions (no ‘Seligmann effect’). In S. punctatus, extents and directions of sexual dimorphism paralleled differences between tail-retainers and tail-losers, females resembling tail-losers, also accounting for character interdependence (developmental constraints; employing a method similar to phylogenetic contrasts). The variation in the location of tail injury was correlated with the continuum of variation between injured and intact (pholidotic) morphotypes. These last two phenomena remain to be explored in Squamates. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 93, 721–743. [ABSTRACT FROM AUTHOR]

The reviving Hebrew language requires an artificially enriched vocabulary for animals. This is created advisedly by the Academy of the Hebrew Language and its Committee for Zoological Terms, who hold that, (a) vernacular names serve in communication and should be educational; (b) therefore they should be generally accepted, unambiguous, stable, instructive, and of reasonable scope; each name should be meaningful, simple, convenient, and preferably pretty. The Committee has defined the scope of the required vocabulary and decided that the Hebrew system should reflect the scientific nomenclature, with three main modifications: (a) The Hebrew genus is a practical one, comprising species related in the eyes of amateurs; taxonomic and nomenclatural changes need not affect the Hebrew terms. (b) Famous species may carry single-word names. (c) A family name may derive from the name of a genus prominent in Israel. Names are recruited from the following sources: (a) Biblical and later scripture. (b) Modern common usage. (c) Scientific or foreign vernacular names. (d) New, coined by the Committee. After adequate discussion, involving the public, the names are decided by the Academy and published. The process may serve as model for similar enterprises. [ABSTRACT FROM AUTHOR]

A study aimed at testing the contested validity of the subspecies Laudakia steltio daani yielded novel insights into the essence of subspecies. We examined morphologically museum specimens from Greece, Aegean islands, and Anatolia (n=118; not all could be used in all analyses). Beyond the conventional mensural, meristic and qualitative characters we quantified 14 coloration characters, thus totalling 34 characters (including sex). Biometry was statistically analysed within and between the two geographically defined presumed subspecies, L. s. daani and L. s.Stelio. Excluding or including broken-tailed specimens changed the outcome of tests. Significant minor directional asymmetry occurred in one of four character-taxon combinations. Phenetic cluster analysis poorly separated the two presumed subspecies when all characters, including those with discordant variation, were included; after selection of characters, the separation improved. Some biometric characters distinguish the two presumed subspecies, conforming their validity. The associations of significant inter-character correlations differed between the two subspecies. Additionally, the two differed in parameters reflecting selection pressures and social structure: L. s. stellio is more colourful than L. s. daani; its sexual dimorphism is mainly chromatic, versus mensural in L. s. daani, and its population seems to include many males with underdeveloped callous scales, presumably socially subordinate, versus very few in L. s. daani. [ABSTRACT FROM AUTHOR]

Taxonomic families of insectivorous lizards are usually characterized by one of two distinct foraging modes, namely ambush 'sit-and-wait' or active 'widely foraging'. In the Gekkonomorpha the situation has been unclear and in dispute, and among these, that in the Sphaerodactylini is almost unreported. We, therefore, examined the foraging mode of three sphaerodactylin species on Trinidad and Tobago, in May-June 2000 (totalling 72 individuals, observations averaging 23.6 min/individual ). In terms of species averages, Gonatodes vittatus, G. humeralis and G. ocellatus all moved for only 1.6-3.55% of observation time (PTM, percent time moving), and switched from sitting to locomoting only 0.18-0.36 times per minute (MPM, moves per minute). The genus thus is a strict sit-and-wait forager. In G. vittatus, the foraging mode was una3ected by sex or habitat structure. In all three species, foraging mode was una3ected by the time of day or air temperature. In G. humeralis, foraging activity (PTM or MPM) correlated with light intensity in the forest within a population (at least MPM) and among populations (at least PTM). Among the three species, too, foraging activity (PTM and MPM) ranked with light intensity during sampling. In all three species, the geckos perched for 68-76% of the time (at any height) with the head pointing down, apparently so as to see better. In conclusion, the three species are strict 'sit-and-wait' visual hunters that are dependent on light. [ABSTRACT FROM AUTHOR]

In the present pilot study the effect of the venom of the Israeli yellow scorpion (Leiurus quinquestriatus hebraeus (Birula, 1908)) on two Israeli fan-toed gecko lizards (Ptyodactylus guttatus von Heyden, 1827 and P. puiseuxi Boutan, 1893) was examined through (1) observations on feeding behaviour and (2) toxicity assays. It was shown that (1) the geckos ate the extremely venomous yellow scorpions in a sting-avoiding fashion and when occasionally stung they were not affected; (2) subcutaneous injections of lyophilized venom were survived by the scorpion-sympatric P. guttatus in doses of 1 mg of crude lyophilized venom per g of body weight (4000 times its I-Dso value for mice), in contrast with the presumably allopatric P. puiseuxi which died within 80 and 210 min from doses of 1 and 0.5 mg per g, respectively. The pharmacological and ecochemical aspects of the above tolerance are discussed. [ABSTRACT FROM AUTHOR]

Congenital morphological differences between injured and intact individuals in a population may reflect adaptations to avoid injury, to survive injury, or both. We explore the possible occurrence of such adaptations, analysing the relationship between tail state (original, O; regenerated, R) and morphology (20 scale characters) in 23 taxa of Lacertidae. In some taxa, such as Acanthodactylus opheodurus, morphologies of O and R lizards differed significantly. In these, usually O individuals were morphologically typical (modal), while R individuals were extreme; in others, the contrary occurred. Indices of pattern similarity detected fewer differences between O and R lizards than those based on absolute values. We developed unbiased estimates of classification rates of discriminant analysis. The order of inclusion of characters in the discriminant functions of males and females of the same species differed more than the order for the same sex in other species. Some morphological differences between O and R lizards seem adaptive or linked by pleiotropy to adaptive traits. Congenital morphological differences between O and R lizards are probably more frequent than detected because we show that age and geographical heterogeneity of our samples are confounding factors to O-R differences. R-morphologies might reflect microevolution in favour of paedotypic forms, possibly possessing greater regenerating capacities than relatively more peratypic forms. [ABSTRACT FROM AUTHOR]

Textbooks lump the middle ears of ‘submammalian Tetrapoda’ as being ‘one-ossicle ears’. Conventionally the anuran middle ear is depicted with a shaft-like skeletal unit connecting the tympanic membrane to the inner ear. This shaft comprises mediad a long bony columella and laterad a short cartilaginous extracolumella. But dissection of Rana catesbeiana ears showed: the extracolumella, as long as the columella, is proximally expanded in the vertical plane, forming dorsal and ventral heads. The medio-dorsal head is movably jointed to the columella, between these two there is an obtuse angle ventrad; the extracolumellar medio-ventral head is anchored by a ligament to the middle-ear cavity ceiling. When the tympanic membrane moves outwards, pulling the extracolumella, the medio-dorsal head of the extracolumella must be forced inwards, rotating on the ventral anchorage, pushing the columella towards the inner ear. The ossicular chain thus includes a mechanical lever, possessing the magnitude of the ratio length:width of the extracolumella; this is additional to the lever known from the columellar footplate, which rotates on its firm ventral attachment. These levers are confirmed physiologically, by the difference between the inner-ear sensitivity (shown by isopotential audiograms of microphonic potentials) when stimulated by a vibrator first at the tympanic membrane, then at the proximal stump of the amputated columella. Perusal of the primary literature showed that this morphology is widespread among anuran ears. [Copyright &y& Elsevier]

Previous studies of electrophysiological audiograms in gekkonomorph lizards revealed greater sensitivity in adults than in juveniles. We investigated whether this difference, as far as it is affected by the middle ear, is due to animal age or size. The velocity transfer function of the tympanic membrane (TM) was examined using laser interferometry in nine samples: adults of three large gekkonomorph species, adults of three small species (each related to one of the former), and juveniles of the large species, their sizes matching those of the small-species adults. Each transfer function exhibited an inverted 'V' or 'U' shape, with the velocity of TM motion peaking in the mid-frequency range and becoming poorer at lower and higher frequencies. Among samples, maximum TM velocity correlated with animal length, perhaps because of a damping change in the larger TM. The frequency at maximum velocity negatively correlated with measurements of TM area. Presumably, with a larger TM area, the best frequency shifted downward because of increased middle-ear mass or decreased stiffness. The bandwidth of the transfer function negatively correlated with animal length, being broader in smaller animals and sharper in larger animals. This effect can be attributed to increased mass, decreased damping, or both. Among the middle-ear morphological measurements, the one most closely correlated with body length was the length of the extracolumellar anchorage at the TM. Among the physiological variables investigated, maximum velocity was negatively correlated with the frequency at which it occurred. The dependence of these transfer function variables on animal and ear size was similar, regardless of whether the comparison was among adults of species of different sizes, or among age classes within a species, so that age differences appear to be largely the result of size differences. [ABSTRACT FROM AUTHOR]

Wishing to assess the effects of the dimensions of the middle ear on the auditory sensitivity of gekkonoid lizards, we measured middle ear components in preserved geckos, which in life had yielded ‘cochlear microphonics’ audiograms. We examined two to seven specimens of 14 species. The measures of middle ear elements varied relative to head or body length similarly within species and among species. The areas of the external ear opening, tympanic membrane, and columellar footplate, and the ratio between the last two (‘hydraulic lever’), were correlated with animal length. The hydraulic and mechanical (extracolumellar) lever ratios appeared to complement each other, the former being emphasized in large animals, the latter in small animals. The apparent auditory sensitivity correlated with the sizes of the animal, head and external ear opening, and negatively (insignificantly) correlated with the mechanical lever ratio. The correlation of sensitivity with the hydraulic lever was insignificant, perhaps due to a ‘tympanic membrane lever’ (catenary effect). The most sensitive frequency negatively correlated with the area of the external ear opening, the area of the tympanic membrane, and with the level of greatest sensitivity. It was positively correlated with the relative length of the cartilaginous portion of the ossicular chain. However, the number of hair cells in the basilar papilla, too, is known to correlate with animal size. Moreover, the least sensitive species were not only the smallest species, they were also the species known to lack a zone of unidirectional hair cells in the basilar papilla. Hence the apparent sensitivity hypothetically depends on both middle ear dimensions and summation of inner ear output. This hypothesis requires verification by other methods. [Copyright &y& Elsevier]

Investigates whether changes in auditory function accompany increases in the body size of gekkonoid lizards. Study of middle-ear structure of adult and juvenile Eublepharis macularius and Oedura marmorata; Compound action potentials (CAPs) which were used as an indication of peripheral auditory function; Study of tympanic membrane velocity; Results, which indicated that significant changes occurred between the younger and older animals.

1. Regeneration of the caudal axial skeleton in the gekkonid lizard Hemidactylus turcicus L. was investigated, after autotomy, after intervertebral amputation and after amputation within an earlier regenerate. 2. There always follows a latent period during which osteoclasts (or chondroclasts) cut off the equivalent of a quarter-vertebra which is consequently lost. This process is termed ablation. 3. Analysis of evidence in the literature suggests that loss of a quarter-vertebra (through either ablation or absorption) precedes tail regeneration in other geckos and Lacerta as well. 4. After ablation a regenerate grows, in which the vertebral column is represented by an unsegmented cartilage tube. Development of this tube is described. Its structure conforms in the main to previous descriptions. 5. Tissue within the intersegmental, midvertebral, autotomy split apparently does not participate in tail regeneration following autotomy. Similarly, it is not clear whether tissues from the site of the original injury give rise to the blastema for tail regeneration, in saurians. 7. In the process of ablation within an earlier regenerate, chondroclasts appear at a considerable distance from bony tissue. They seem to be identical with osteoclasts. 8. Growth rate of the regenerate appears to be similar after all three types of amputation. 9. Earlier descriptions of tail regeneration, as far as pertinent, are discussed. [ABSTRACT FROM AUTHOR]

Prudent use of the limited conservation resources rests on solid taxonomy data. This is a critical review of a taxonomy paper aimed at conservation but in itself not fully reliable ("Genetic evidence for premature taxonomic inflation in Middle Eastern tortoises", Parham et al., 2006, Proc. Calif. Acad. Sci. 57: 955-964). Its authors consider that unjustified naming of species is detrimental to conservation. This reviewer considers the paper flawed in (a) selection and reportage of voucher specimens, partly erroneous or inaccurate; (b) methods; (c) scientific reasoning and conclusions; and (d) clarity of argumentation. Hence even if the results are supported by the more solid results of others, the paper in itself is considered not to be sufficiently reliable for systematics or conservation. [ABSTRACT FROM AUTHOR]

The article examines field body temperatures (FBTs) of three Ptyodactylus species in Israel and compares them with their preferred body temperatures (PBTs).