Yehudah L. Werner

Foraging mode in lacertid lizards: variation and correlates

Foraging strategy was observed in five species of Israeli lacertid lizards in the field. Acanthodactylus scutellatus is a sit-and-wait strategist, whereas A. boskianus, A. schreiberi, Lacerta laevis and Mesalina guttulata forage widely. However, the actual values differed from those reported by Huey and Pianka (1981) for Kalahari lacertids, possibly indicating the existence of a continuum of foraging modes. Foraging intensity (proportion of time spent moving or frequency of moves) is positively correlated to relative tail length, and negatively correlated to relative clutch mass. Additional possible correlates are discussed, and some cautionary remarks added.

The Middle Ear of Reptiles and Birds

The middle-ear system of all vertebrates improves the efficiency of sound transmission from the surrounding medium, be it air, water, or ground, to the inner ear. The process by which this is achieved is similar across both mammalian and nonmammalian forms. The specific structures and mechanisms that have evolved to accomplish this task, however, vary considerably from species to species. In this chapter we hope to develop an appreciation of how the middle-ear system is organized, how it operates, and how it contributes to hearing in reptiles and birds. The chapter begins by examining how the middle ear is studied and how it functions. A brief exposition of middle-ear evolution is followed by a consideration of structure and function in the reptilian and avian middle ears. The contribution of middle-ear muscle contraction as well as middle-ear development is then presented. Finally, the chapter concludes with a discussion of the contribution of the middle ear to the overall process of hearing in these species.

Australian geckos do not display diel variation in thermoregulatory behavior

Body temperature (Tb) influences almost every aspect of a reptiles physiology and behavior (for reviews, see Huey, 1982; Lillywhite, 1987). For example, Tb can alter both auditory capacity (Werner, 1976, 1983) and locomotory performance (Bennett, 1980, 1990), thus facilitating or impairing escape from and defense against predators (e.g., Christian and Tracy, 1981; Hertz et al., 1982; Goode and Duvall, 1989), prey capture (Greenwald, 1974), and prey handling (Van Damme et al., 1991). Energy available for allocation to growth and reproduction is determined by digestive and metabolic processes, both of which are temperature-dependent (Bennett and Dawson, 1976; Waldschmidt et al., 1986; Van Damme et al., 1991). In viviparous species, the development of offspring depends on the Tb of the gravid mother (Bull, 1980). Thus, Tb can have both direct and indirect consequences for fitness. For many physiological processes (e.g., locomotion, feeding, digestion), the rate of function is maximal over some range of TbS and decreases rapidly above and below this range (Huey, 1982). Field studies of thermoregulation (e.g., Peterson, 1987; Christian and Weavers, 1996) indicate that many reptiles maintain relatively high and constant TbS during activity. Presumably, thermoregulatory behavior allows animals to function over a range of TbS that is conducive to the requisite physiological processes (e.g., locomotion, digestion). However, field TbS do not indicate temperature preference. For many reptiles, tropical environments may provide stable thermal climates such that a narrow range of TbS may be achieved with little effort (Shine and Madsen, 1996). In other cases, individuals may accept TbS that are higher or lower than preferred temperatures due to constraints on their thermoregulation imposed by the environment (Huey and Slatkin, 1976). Clearly, field TbS cannot be strictly interpreted as measures of Tb preferences in reptiles. Preferred body temperature (Licht et al., 1966) has been used as an estimate of body temperature preferences in reptiles. Preferred body temperature (T,) is the Tb maintained by an organism free from all ecological constraints and is measured in a laboratory thermal gradient that provides a full range of equally accessible thermal environments. Measures of T, are useful because they indicate the temperature that n ganism tries to attain during thermoregulation in nature (Hertz et al., 1993). Integrated

The case of impact factor versus taxonomy: a proposal

Scientists are racing to discover and describe new species in the face of a global biodiversity crisis (Stuart et al. 2006). The numbers of animal species awaiting description, that sometimes would be the key to their becoming protected, may be declining more rapidly through extermination than through some of the species becoming described. Unfortunately, obstacles to systematic research are mounting. Some complications for systematics are unavoidable objective consequences of recent research progress. Such are the accumulating evidence that traits earlier considered genetic may actually be modified by environmental factors during embryogenesis (e.g. Osgood 1978; Elphick and Shine 1998), and the new evidence that those individuals that morphologically most clearly deviate from the population average may be accident prone, presumably possess lower fitness, and conceivably are taxonomically irrelevant. For example, sometimes related lizard taxa are easier to distinguish once all individuals with incomplete tails are excluded from the analysis (Almog et al. 2005; Lachman et al. forthcoming). Against this backdrop it is deplorable that recently an artificial obstacle has been developing: the impact factor. Even the best species descriptions, unless within major phylogenetic revisions, usually do not and cannot attract much citation (except when uniquely controversial), because most taxonomic groups are researched by very few taxonomic specialists, if any. Therefore journals that carry many such papers score a low impact factor. They then become less attractive to authors of ‘‘good’’ papers, and the process ‘‘escalates’’ downhill. This process dissuades and repels young biologists from taxonomy, especially since many universities, beyond bowing to the impact factor, actually abuse it through respecting its numerical value without regard to reference group. One cannot equate zoology with medicine, or within zoology, taxonomy with ecology, but few deans stoop to such minutiae. Trying to enlighten and reform university authorities may be a ‘‘mission impossible’’ but a potential remedy does exist. Traditionally, the first mention of a species name within any

More injuries in left-footed individual lizards and Sphenodon

In lizards and Sphenodon, often the fourth toes of individuals with intact tails have more subdigital lamellae on the right than on the left side, and the opposite situation frequently occurs in individuals with injured tails. The difference between intact and injured individuals in morphological directional asymmetry was statistically significant (P<0.05) in 11.4% among 193 species from various lizard families. Lizard families varied in extent and direction of association, but no phylogenetic constraints were detected within genera. Statistical significance was greater in samples from homogenous geographic origin than from heterogeneous ones. Among gekkonid species, the difference was stronger in those with cursorial (terrestrial) habits, than in those with scansorial (rupestral or arboreal) habits. In Scincidae, loss seems more often lethal in left-footed than in right-footed individuals. Statistically significant associations between morphological left-side dominance and tail injury exist also in three independent lineages with reduced limbs (Anguidae, Scincidae and Teidae). Hence such association is probably not a result of limb function. Rather, left-side dominance seems to be the symptom of an unknown, perhaps organism-wide, detrimental trait. Polymorphism in morphological dominance existed in all species, suggesting advantages and disadvantages in different situations to both phenotypes. We propose the hypothesis that an inversion of side dominance may occur in a single trait without systematic inversion of side dominance in all traits of the body. Inversion in a single trait causes incompatibility in multiple-trait functions. Such a mechanism, rather than cultural conventions, could increase accident proneness also in left-handed Homo sapiens, and could explain increased proneness to accident and warfare mortality in left-handed men, beyond the possible involvement of cultural factors.

Systematics and distribution of the Acanthodactylus pardalis group (Lacertidae) in Egypt and Israel

Abstract Examination of 385 specimens of the Acanthodactylus pardalis group from eastern Libya, Egypt and Israel confirmed the occurrence of two allopatric species in this area: Acanthodactylus pardalis (Lichtenstein, 1823) distributed in Egypt And eastern Libya and a hitherto undescribed species endemic to the Negev (Israel). The species differ most markedly in body size, hemipenial structure, colouration and details of sexual dichromatism. Other significant differences involve scalation and biometrics. A simple method for artefact-free use of discriminant analysis in multivariate classification is presented. Redescription of A. pardalis (Lichtenstein, 1823), description of a new species Acanthodactylus beershebensis sp.n. and corrected geographical ranges of the two species are provided. Both species, each endemic to a small area, appear to be markedly endangered by habitat destruction.

THE STRIPED COLOUR PATTERN AND STRIPED/NON-STRIPED POLYMORPHISM IN SNAKES (REPTILIA: OPHIDIA)*

The occurrence of striped colour patterns and of striped/non‐striped polymorphism systems among snakes is reviewed from literature data augmented by some personal observations. Among 1367 species, 190 were striped or had striped morphs. Of 11 families, the striped pattern was common mainly among Colubridae, presumably in relation to the active escape behaviour strategy, prevalent in this family. The striped species tended to cluster in a small number of genera.

Selected Body Temperature in Diurnal and Nocturnal Forms of Ptyodactylus (Reptilia: Gekkoninae) in a Photothermal Gradient

The three Israeli forms of Ptyodactylus (P. hasselquistii puiseuxi, P. h. guttatus and P. h. hasselquistil) differ in daily activity pattern, being mainly diurnal, diurno-nocturnal and nocturnal, re- spectively. We measured body temperatures of the three forms in a photothermal gradient. They differed significantly from each other in mean selected body temperature, the northern, diurnal P. h. puiseuxi having the highest value of 33.5 + 1.5?C, the southern, nocturnal P. h. hasselquistii having the lowest value of 28.7+1.7?C, and the common, diurno-nocturnal P. h. guttatus having an intermediate mean selected body temperature of 30.9 ? 2.4?C. Frequency distributions of body temperatures revealed modes of 35?C in P. h. puiseuxi, and 28?C in P. h. hasselquistii, and a bimode of 30?C and 34?C in P. h. guttatus. P. h. hasselquistii chose significantly lower ambient temperatures and had a significantly wider range of body temperatures compared with P. h. guttatus. The diurnal P. h. puiseuxi maintained a significantly greater body-to-air temperature difference than both other forms. We conclude that the selected body temperatures of the three forms are closely associated with their different daily activity patterns and with their distinct ecological distributions.

Habitat-dependent thermal regimes of two hawaiian geckos (Reptilla: gekkonidae)

Abstract 1. 1.Effects of habitat on the thermal regime were investigated in two diurno—nocturnal geckos in Hawaii. 2. 2.In trees Hemidactylus frenatus thermoregulated in daytime with body temperature (BT) above air temperture (AT); in houses some thermoregulated likewise in daytime but mainly the species thermoregulated at night, on electric lamps, to the same BT as in trees by day. 3. 3. Lepidodactylus lugubris in trees thermoregulated in daytime, its BT lower than in H. frenatus . In the rocks it had at night a BT resembling that in trees in daytime, because the thermal cycle in rock crevices lagged behind outside AT. 4. 4.The flexibility of these geckos in thermal regime and activity cycle preadapts them to both migration and invasion of houses.

Radiation and convergence among desert geckos: Phyllodactylus species resembling both Ptyodactylus and Stenodactylus

Using field observations and museum material, we compare environmental, morphological and biological aspects of some Peruvian and Israeli desert lizards (Reptilia: Gekkonidae). The rupicolous species Phyllodactylus reissi (Peru) resembles Ptyodactylus hasselquistii (Israel) whereas the psammophilous Phyllodactylus microphyllus (Peru) resembles Stenodactylus sthenodactylus (Israel). The similarities include habitat, activity timing, body size, body shape, scutellation, digit structure, eye size, sexual size difference and clutch size. Hence new world Phyllodactylus have radiated attaining a divergence paralleling that between very distinct old world genera.