Geographic variation for colour in the sandburrowing beetle Chaerodes trachyscelides White (Goleoptera: Tenebrionidae) on New Zealand beaches analysed using CIELAB L * values

Chaerodes trachyscelides White is a highly specialized, flightless burrowing beetle confined to the narrow strip of sand at and just above high water level on sandy marine beaches in New Zealand. Although the ventral surface of the beetle is always pale, the dorsal surface varies from pale to almost black. Large samples of this beetle were taken, together with the sand, from 11 beaches on New Zealand's three main islands. The colour of the dorsal surface of each individual beetle and that of the sand samples was measured using reflectance spectroscopy and expressed as CIE L*,a*,b* (CIELAB) values. The L* values, which are objective, quantitative measures of the degree of lightness of the beetles, were subjected to statistical and frequency analysis. Although the species was very variable in colour and the variation appeared to be continuous, a highly significant correlation was obtained between the mean of the L* values for the samples on each beach and that of the sand, the correlation coefficient being 0.961. This close association between the lightness of the beetles and that of the sand suggests the variable melanism functions as cryptic colouration. On most beaches, the distribution oflightness among the beetles sampled conformed to a normal curve. For beetles from sites where the sand was relatively uniform, such as the black Taranaki beaches, the L* frequency distribution curves were narrow and the coefficient of variation of mean beetle colour was relatively small indicating low colour variability. In contrast, the greatest within-site variability occurred on the two Stewart Island beaches sampled, where in each case there was less uniformity in the colour of the sand. At one of these sites, Maori Beach, darker sand present below the high water level is often deposited on the zone occupied by the beetles after storms. On Lonneker's Beach, the distribution of L* values among the beetles sampled was actually bimodal. On this small beach, there was an area of intensely black sand in the zone occupied by the beetles, but most of the rest was covered with light golden sand. These results are interpreted as evidence that the variability of colour of Chaerodes beetles has the effect of populations being able to match the colour of the sand of their home beaches, presumably as a consequence of the differential survival of individuals.     

Composition of the early Oligocene ocean from coral stable isotope and elemental chemistry

A sectioned and polished specimen of the coral Archohelia vicksburgensis from the early Oligocene Byram Formation (～30 Ma) near Vicksburg, Mississippi, reveals 12 prominent annual growth bands. Stable oxygen isotopic compositions of 77 growth‐band‐parallel microsamples of original aragonite exhibit well‐constrained fluctuations that range between ?2.0 and ?4.8. Variation in δ¹⁸O of coral carbonate reflects seasonal variation in temperature ranging from 12 to 24 °C about a mean of 18 °C. These values are consistent with those derived from a bivalve and a fish otolith from the same unit, each using independently derived palaeotemperature equations. Mg/Ca and Sr/Ca ratios were determined for 40 additional samples spanning five of the 12 annual bands. Palaeotemperatures calculated using elemental‐ratio thermometers calibrated on modern corals are consistently lower; mean temperature from Mg/Ca ratios are 12.5 ± 1 °C while those from Sr/Ca are 5.8 ± 2.2 °C. Assuming that δ¹⁸O‐derived temperatures are correct, relationships between temperature and elemental ratio for corals growing in today's ocean can be used to estimate Oligocene palaeoseawater Mg/Ca and Sr/Ca ratios. Calculations indicate that early Oligocene seawater Mg/Ca was ～81% (4.2 mol mol^?1) and Sr/Ca ～109% (9.9 mmol mol^?1) of modern values. Oligocene seawater with this degree of Mg depletion and Sr enrichment is in good agreement with that expected during the Palaeogene transition from ‘calcite’ to ‘aragonite’ seas. Lower Oligocene Mg/Ca probably reflects a decrease toward the present day in sea‐floor hydrothermal activity and concomitant decrease in scavenging of magnesium from seawater. Elevated Sr/Ca ratio may record lesser amounts of Oligocene aragonite precipitation and a correspondingly lower flux of strontium into the sedimentary carbonate reservoir than today.     

Movement of Anopheles gambiae s.l. malaria vectors between villages in The Gambia

ovement of mosquitoes belonging to the Anopheles gambiae complex (mixed wild populations of An.arabiensis, An.gambiae and An.melas ) between three neighbouring rural villages in The Gambia was investigated by mark-release-recapture. A total of 12,872 mosquitoes were collected in bednets, marked with a magenta fluorescent powder and released over a 15-day period in one of the villages. A further 15,507 mosquitoes were collected in exit traps, marked with a yellow powder and released over the same period. Mosquitoes were captured daily in all three villages using pyrethrum spray catches, as well as bednet and exit trap catches. The catching period extended for 6 days after the last day of release.
Of the mosquitoes released, 372 (1.3%) were recaptured 2–21 days later. Of these recaptures, 272 were caught in the release village, and 98 were caught in other villages situated 1–1.4 km away. The 'movement index' between villages was calculated as 17.2% (12.2–22.4% confidence limits) for mosquitoes released after feeding and 20.1% (14.7–25.3%) for those released unfed.
These results suggest that movement of mosquitoes between neighbouring villages in The Gambia seriously affects the entomological evaluation of pyrethroid-impregnated bednet programmes in areas where treated and untreated villages are interspersed.     

Breeding success and chronology of Wood Storks Mycteria americana in northern and central Florida, U.S.A.

The breeding success and chronology of Wood Storks Mycteria americana were studied at eight colonies in northern and central Florida during 1981–1985. Mean ± s.d. clutch size for all colony-years was 3.07 ± 0.56 (n = 2694 nests), with three-egg clutches (72%) most frequent. Mean clutch size among all colonies and years ranged from 2.73 ± 0.55 to 3.41 ± 0.61. Many colonies exhibited significant negative trends in clutch size with, hatching date because of a proportional decrease in four-egg clutches later in the season. Mean colony clutch size was not correlated with nest numbers, nesting density or mean hatching date within most years. Mean ± s.d. number of fledglings for all colonies and years was 1.29 ± 1.16 fledglings per nest (n = 2812 nests). Mean annual fledging rates in colonies ranged from 0 (colony failed) to 2.66 fledglings per nest. Most breeding failure occurred prior to egg hatching, and the second highest mortality occurred between hatching and 2 weeks of age. Four-egg clutches fledged more storks than three-egg clutches, which in turn were more successful than two-egg clutches. However, all clutch sizes showed similar fledgling per egg rates. The seasonal decline in productivity was associated proportionally with smaller clutch sizes later in the breeding season. An increase in mean hatching date was correlated with an increase in latitude. There was greater within-year breeding synchrony among colonies than interyear breeding synchrony within each colony. Breeding synchrony was not correlated with mean hatching date, latitude, longitude, nest numbers or nesting density.     

Effects of CCC on the Formation and Abortion of Flowers in the First Inflorescence of Tomato (Lycopersicon esculentum Mill.)

Treatment of tomato plants with (2-chloroethyl)trimethylammoniumchloride (CCC) reduced their growth in height and d. wt andincreased the number of flowers formed in the first inflorescence.In plants grown at a high temperature with low light, applicationof CCC reduced the incidence of flower abortion in the firstinflorescence. Effects of -cyclopropyl--(4-methoxyphenyl)--(pyrimidin-5-yl)methanol(ancymidol) were similar to those of CCC while a third growthretardant, N-dimethylaminosuccinamic acid (B-9), was effectivein reducing growth in height but was without apparent effecton flower number or flower abortion. An interaction occurred between CCC and GA₃ such that effectsof CCC on growth and flowering were reduced when GA was alsoapplied. Yields of diffusible gibberellin-like substances fromthe shoot tips were markedly reduced by treating plants withCCC but were apparently not affected by treating plants withB-9. It is suggested that effects of CCC on flowering in tomatoare mediated, in part at least, through changes in levels ofendogenous gibberellins.     

Effects of Glyphosate on Metabolism of Phenolic Compounds

Light enhanced the inhibiting effect of root-fed glyphosate (5 × 10^?4M) on dry weight accumulation of soybean [Glycine max. (L.) Merr.] seedling axes. Inhibition of growth by light was greatest in hypocotyls, whereas by glyphosate it was greatest in roots. A synergistic effect of light and glyphosate on stimulation of phenylalanine ammonia-Iyase (PAL, E.C. 4.3.1.5) activity was also demonstrated. In continuous white light PAL activity increased linearly for 4 days in axes of seedlings exposed to glyphosate. Evidence of phytochrome involvement in the light effect was shown. The stimulatory effect of glyphosate on PAL activity was greater in roots than in hypocotyls. Soluble hydroxyphenolic compound levels were reduced by glyphosate but were increased by light on a per axis basis. On a fresh weight basis, hydroxyphenolics were more concentrated in glyphosate-treated than in control tissues in the light. When compared to other amino acids, disproportionate decreases in free pools of phenylalanine and tyrosine occurred in axes of seedlings treated with glyphosate and light. The effect of light on all measured parameters was mainly in the hypocotyl, while that of glyphosate was primarily in the root. In the light, glyphosate caused increases in levels of glutamine and other amino acids that may be the result of amination reactions, protecting from excess ammonia generated by enhanced PAL activity. These results suggest that PAL has a strong influence on its substrate levels in this system and/or that glyphosate inhibits synthesis of aromatic amino acids.     

Ultrastructure of Endosperm Protein Bodies in Developing Rice Grains Differing in Protein Content

Ultrastructural aspects of the development of protein bodies(aleurone grains) in endosperm of grains of two rices differingin protein content are described. Formation of rough endoplasmicreticulum complexes prior to protein deposition was observedonly in the higher protein grain. From 8 days after floweringthree types of protein body were observed, one of which wasrestricted to the peripheral endosperm (sub-aleurone) layers.The higher protein grain had a greater number of protein bodiesand rough endoplasmic reticulum in the endosperm cells thanthe lower protein grain. Increase in total protein with maturitywas the result of increased number of protein bodies ratherthan increase in size; the protein bodies were concentratedin the peripheral endosperm layers.     

An Ultrastructural Investigation of 180°-Rotated Ciliary Meridians in Tetrahymena pyriformis*

SYNOPSIS. An ultrastructural investigation has been carried out on 180°-rotated ciliary meridians (inverted meridians) in Tetrahymena pyriformis temperature-sensitive mutant (mol^b/mol^b), syngen 1, strain B. The longitudinal, transverse and postciliary microtubular bands, the kinetodesmal fiber, and the parasomal sac, are shown to be disposed at a 180° angle to their normal positions or orientations. Other abnormalities are as folows: the first 2 basal bodies of the inverted meridian fail to organize into “couplets” and the inverted meridian intrudes into the anterior pole region; an extra longitudinal microtubular band is found in one of the cell lines.