Regeneration and growth of coolibah,Eucalyptus coolabah subsp. arida,a riparian tree,in the Cooper Creek region of South Australia

Abstract Regeneration patterns of Eucalyptus coolabah Blakely & Jacobs subsp. arida (Blakely) L. Johnson & K. Hill (coolibah), a riparian tree of inland Australia, were inferred from size classes at two locations in South Australia; part of the floodplain of Cooper Creek and a swale in the Strzelecki Desert. These had contrasting water regimes; Cooper Creek floods on average once every 5–6 years whereas the swale has a continual water supply from a bore. A peak in size class distribution showed a regeneration event at each location but at different times. The one in the swale was more recent and was dated to the mid-1970s using aerial photography. Young (< 5 m tall) trees, interpreted as recent regeneration, were concentrated on specific topographic features, the top of a steep riverbank and a sand mound separate from the main dune system. Access to these features would have been difficult after flooding suggesting regeneration is dependent on protection from introduced herbivores. Field observations of reproductive status and canopy die-back showed coolibah condition was better in the swale. The relatively poorer condition of floodplain coolibahs was attributed to saline soils compounded by drier conditions rather than age.     

Interactions between seed priming treatments and nine seed lots of carrot, celery and onion. II. Seedling emergence and plant growth

Samples of three seed lots of each of three cultivars of carrot, celery and onion were primed in polyethylene glycol solution for two weeks at 15 °C. Seedling emergence was recorded in the field for carrot and onion and in the glasshouse for celery. Compared to the untreated control, priming increased the percentage seedling emergence in certain poorly-emerging seed lots of carrot and celery, but had no effect on onion. Mean emergence times were reduced by priming in all seed lots, by 3–5, 5–8 and 3–9 days in carrot, celery and onion respectively. The largest effects occurred in the slowest-emerging seed lots. There were significant interactions between priming and seed lots within cultivars in carrot and celery and between priming and cultivars in celery and onion. Priming generally reduced the spread of emergence times, but the effects were not statistically significant in carrot. Drying back the primed seeds had no effect on percentage emergence in onion, but reduced it (compared to primed seed which had not been dried-back) in certain carrot and celery seed lots. Primed and dried-back seeds emerged later than primed seeds, by up to 1·5, 2·6 and 2·6 days in carrot, celery and onion respectively. The spread of emergence times was generally larger for primed and dried-back seeds than for primed seeds, but the differences were not always statistically significant. Plant fresh weights were recorded 9, 7 and 12 wk after sowing for carrot, celery and onion, respectively. In each species, mean plant weight was inversely related to seedling emergence time; thus plants grown from primed seed were always heavier than the controls, by up to 33%, 182% and 47% in carrot, celery and onion respectively.     

Assessment of body condition in live birds; measurements of protein and fat reserves in the mute swan, Cygnus olor

Condition in animals is often measured in relation to various demands, such as reproduction, migration and cold weather. Usually, indices of protein and fat reserves have to be measured on dead animals. Measurements on live animals enable variations in the condition of individuals to be monitored over time, and can be related to their life histories.
In birds, the size of the breast muscle is the most commonly used measure of protein reserves. A technique for measuring breast muscle thickness was developed, using ultrasound, and was tested on mute swans. The measurements were accurate and highly repeatable. Breast muscle thickness was positively related to the lean dry weight of the breast muscle, and is likely to be a good indicator of total protein reserves.
A system of fat scoring by colour was developed to assess the size of the subcutaneous fat layer. Although the method relies on subjective judgements, the results were highly correlated with the percentage of fat in the subcutaneous layer, and with other measures of fat reserves.
Measurements were made on live, non-breeding swans to monitor seasonal variations in reserves. The seasonal pattern of fat reserves was similar to the normal cycle of weight changes; high in winter and low in summer. There was no change in relation to the moult. No distinct seasonal variation in muscle thickness was found.
There is an unusual pattern of change in the relative size of reserves during emaciation in swans. Muscle reserves appear to be depleted to a greater extent than fat reserves. This is possibly due to the effects of lead poisoning, causing protein necrosis and preventing muscle regeneration.     

Modelling and analysing evolution of dispersal in populations at expanding range boundaries

Abstract 1. Species would be expected to shift northwards in response to current climate warming, but many are failing to do so because of fragmentation of breeding habitats. Dispersal is important for colonisation and an individual‐based spatially explicit model was developed to investigate impacts of habitat availability on the evolution of dispersal in expanding populations. Model output was compared with field data from the speckled wood butterfly Pararge aegeria, which currently is expanding its range in Britain. 2. During range expansion, models simulated positive linear relationships between dispersal and distance from the seed location. This pattern was observed regardless of quantity (100% to 10% habitat availability) or distribution (random vs. gradient distribution) of habitat, although higher dispersal evolved at expanding range margins in landscapes with greater quantity of habitat and in gradient landscapes. Increased dispersal was no longer evident in any landscape once populations had reached equilibrium; dispersal values returned to those of seed populations. However, in landscapes with the least quantity of habitat, reduced dispersal (below that of seed populations) was observed at equilibrium. 3. Evolutionary changes in adult flight morphology were examined in six populations of P. aegeria along a transect from the distribution core to an expanding range margin in England (spanning a latitudinal distance of >200 km). Empirical data were in agreement with model output and showed increased dispersal ability (larger and broader thoraxes, smaller abdomens, higher wing aspect ratios) with increasing distance from the distribution core. Increased dispersal ability was evident in populations from areas colonised >30 years previously, although dispersal changes were generally evident only in females. 4. Evolutionary increases in dispersal ability in expanding populations may help species track future climate changes and counteract impacts of habitat fragmentation by promoting colonisation. However, at the highest levels of habitat loss, increased dispersal was less evident during expansion and reduced dispersal was observed at equilibrium indicating that, for many species, continued habitat fragmentation is likely to outweigh any benefits from dispersal.     

The diversity and biogeography of koa-finches (Drepanidini: Rhodacanthis), with descriptions of two new species

All known populations of koa-finches, genus Rhodacanthis , became extinct in the Holocene epoch. Two new species are described here from Quaternary fossil sites in the Hawaiian Islands. One new species, from Kauai and Maui, is roughly the size of the historically known greater koa-finch ( R. palmeri ) but differs in having a more robust skull and in bill morphology. The second new species, from Oahu and Maui, is similar in size to the lesser koa-finch ( R. flaviceps ) but closer to R. palmeri in qualitative osteological traits. The two species of koa-finches known historically from the island of Hawaii are distinct in osteology from the fossil koa-finches on the older Hawaiian islands, indicating that at least two of the four known speciation events in the genus took place within approximately the past 500 kyr. However, the similarity of maxillae from Pleistocene and Holocene sites on Oahu suggests that the Oahu population maintained morphological stasis through the climate changes of the late Quaternary. The evidence that speciation occurred on the youngest island in the archipelago suggests that the process of community assembly on newly emergent Hawaiian landscapes was a stimulus to evolutionary diversification in Rhodacanthis .  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 527–541.     

Annotated Index to Genera, Subgenera and Suprageneric Taxa of the Ciliate Order Tintinnida

SYNOPSIS. Supraspecific taxa of the ciliate Order Tintinnida Corliss, 1955 are indexed by 304 entries; genetic type species are cited with reference to the original citation. The accompanying bibliography of 133 entries includes those publications cited in the index. Authors for several type citations are corrected, as is authorship of some genera, and a new type designation is made for Parundella to replace the previous erroneous designation. Genera present in the fossil record are so indicated.