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Kevin van Doorn and Jacob G. Sivak

Edited by J. van Rooijen

The spectral transmittance of the optical media of the eye plays a substantial role in tuning the spectrum of light available for capture by the retina. Certain squamate reptiles, including snakes and most geckos, shield their eyes beneath a layer of transparent, cornified skin called the ‘spectacle’. This spectacle offers an added opportunity compared with eyelidded animals for tayloring the spectrum. In particular, the hard scale that covers the surface of the spectacle provides a unique material, keratin, rarely found in vertebrate eyes, a material which may have unique spectral properties. To verify this, shed snake and gecko skins were collected and the spectral transmittance of spectacle scales was spectrophotometrically analyzed. The spectacle scale was found generally to behave as a highpass filter with a cut-off in the ultraviolet spectrum where taxonomic variation is mostly observed. The spectacle scales of colubrid and elapid snakes were found to exhibit higher cut-off wavelengths than those of pythonids, vipers, and most boids. Gecko spectacle scales in turn exhibited exceptional spectral transmittance through the visual spectrum down into the UV-B. It is suggested that this is due to the absence of beta-keratins in their spectacle scale.

Scott Buchanan, Megan McLean and Todd Tupper

for ∼ 12% (94 / 802 m), ∼ 8% (71 / 880 m) ∼ 10% (13 / 455 m) and ∼ 3% (8 / 304 m) of total shoreline lengths at Duck, Dyer, Kinnacum and Spectacle Ponds (these sites are colloquially termed, ‘ponds’ but are actually lakes; Galvin, 2008), respectively. Water was tannin-lignin poor and mildly acidic

C.C. Doncaster

longer ones, e.g. during time-lapse sequences, it was kept in position to limit evaporation. Condensation droplets can be prevented from forming on cover- glasses by coating them with a thin film of agar or by wiping them with spectacle cleaner, such as 'Calotherm' or 'Spray Kleen' (Heunert, 1971). Fig

Aubrey Manning

to solve problems, not merely to grapple with them. The spectacle of a scientist locked in combat with the forces of ignorance is not an inspiring one if, in the outcome, the scientist is routed. That is why some of the most important biological problems have not yet appeared on the agenda of

Carlo Paoletti, Giacomo Bruni and Antonio Romano

Flank width: distance between the two 4.59 ± 0.37 4.0-5.34 4.92 ± 0.45 4.07-5.81 0.10 3.83-5.43 no tangents of the hind limbs attachment on the body Chromatic measurements SPS Spectacle surface: the light area of the 6.14 ± 1.98 0-10.38 7.03 ± 3.72 0-15.8 ns s p e c t a c l e s HES H ead surface: area

Niels Bolwig

most entertaining spectacle. a. Biting (Fig. 13). As in dogs and cats, fighting and biting is an important feature at the play. Joe and Jenny, particularly Joe, have displayed various types of bite, vary- ing according to mood. i. Sucking bite - has much in common with the babies playing with the teat

William E. Cooper

.E., Schell, F.M. (1988): Comparison of earthworm- and fish-derived chemicals eliciting prey attack by garter snakes (Thamnophis). J. Chem. Ecol. 14: 855-881. Bustard, H.R. (1963): Gecko behavioral trait: tongue wiping spectacle. Herpetologica 19: 217-218. Chiszar, D., Scudder, K.M. (1980): Chemosensory

John Hurrell Crook

. When there are several in the colony at once the spectacle is one of utter chaos. A number of males do however continue displaying at their nests and ultimately it is into the nest of one of these that the female flies. As soon as she is there the male at once goes "dashing to and fro" with great

Nicholas D. Smith, David P. Crabb, Fiona C. Glen, Robyn Burton and David F. Garway-Heath

participant (even if they did not need any correction) to ensure that any restriction to the field of view as a result of spectacle frames was equivalent for each person. 2.4. Analysis The eye tracker automatically extracts and records a number of eye movement parameters. For this study, number

Volker Franz, Constanze Hesse and Thomas Schenk

objects, in: At- tention and performance , J. Long and A. Baddeley (Eds), Vol. 9, pp. 153–168. Lawrence Erlbaum, Hillsdale, NJ, USA. Jeannerod, M. (1984). The timing of natural prehension movements, J. Motor Behav. 16 , 235–254. Milgram, P. (1987). A spectacle-mounted liquid-crystal tachistoscope, Behav