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Latest papers from Royal Society`s Proceedings B (Biological Sciences) and Proceedings A (Mathematical, Physical & Engineering Sciences) journals

July 02, 2002

Proceedings B (Biological Sciences) http://www.catchword.com/rsl/09628452/previews/contp1-1.htm
Age- and density-dependent reproductive effort in male red deer by Dr NG Yoccoz, Dr A Mysterud, Dr R Langvatn and Professor NC Stenseth
Male ungulates spend a large amount of their body reserves when fighting with other males for access to females during the rut. In this study of red deer stags in Norway, weight loss during rut is quantified for the first time. Relative weight loss peaked at prime age, and was lower in younger and senescent males. An average 8 year old stag weighing 135 kg lost an impressive 30 kg in 3-4 weeks time. Weight loss was smaller as density increased, and more so for older males. This is primarily due to (senescent) males starting the rut in poorer condition at high density.
Contact: Professor Nils Stenseth, Division of Zoology, Department of Biology, University of Oslo, PO Box 1050, Blindern, N-0316 OSLO, NORWAY

How an orchid harms its pollinator by Mr BBM Wong and Dr FP Schiestl
Several orchids masquerade as female insects to attract males for the purpose of pollination through sexual deception. We studied the effects of this phenomenon in an Australian orchid that mimics the scent and appearance of female wasps. Our experiments show, for the first time, how orchids harm their pollinators through sexual deceit. We found that male wasps could not discriminate between the scent of orchids and females but learn, instead, to avoid areas with orchids. The orchid, therefore, imposes costs on the pollinator by potentially making it more difficult for females to attract males in the presence of orchid flowers.
Contact: Mr Bob Wong, School of Botany and Zoology, Australian National University, Canberra, ACT 0200, Australia

Rapid recovery of genetic diversity of stomatopod populations on Krakatau: temporal and spatial scales of larval dispersal by Dr PH Barber, Dr MK Moosa and Professor SR Palumbi
Most marine organisms have a developmental stage where larvae enter the plankton for days to months. There is growing interest in whether these dispersive larvae settle in distant or nearby populations; the answer is critical for effective marine conservation efforts. We addressed the geographic and temporal scale of larval dispersal by examining the genetic composition of mantis shrimp populations from Krakatau, an Indonesian island that was effectively sterilized in a catastrophic 1883 erruption. The rapid recovery of genetic diversity shows that marine larvae may frequently recruit from distant (50km) source populations, and that in some cases marine populations can be re-established over historical time.
Contact: Dr P Barber, Department of Organismic and Evolutionary Biology, Harvard University, CAMBRIDGE, MA 02138, USA

Severe inbreeding depression in collared flycatchers (Ficedula albicollis) by Dr LEB Kruuk, Dr BC Sheldon and Dr J Merila
There is universal distaste for incest in human societies, but what happens in nature? We investigated whether individuals in a population of collared flycatchers (a small passerine bird) are similarly programmed to avoid inbreeding - mating with relatives - and what happens if they don`t. We found that inbreeding does occur, but only very rarely. If close relatives do pair up, the implications are severe. A brother-sister pairing will produce only 6% the number of surviving offspring produced by an unrelated pair: inbred chicks are less likely to hatch, smaller, and more likely to die as juveniles. The strength of these effects suggests strong evolutionary selection against pairing with a relative.
Contact:: Dr Loeske Kruuk, Institute of Cell, Animal & Population Biology, University of Edinburgh, West Mains Road, EDINBURGH, EH9 3JT

Analysing noisy time-series: describing regional variation in the cyclic dynamics of red grouse by Dr DT Haydon, Dr D Shaw, Dr IM Cattadori, Professor PJ Hudson and Dr Simon J Thirgood
This study examines shooting bag records from nearly 300 grouse moors across Great Britain for evidence that red grouse populations undergo discernable population cycles. We find that about one fifth of records show no regular dynamical pattern, but that time-series from well over half the moors examined do show evidence of cyclic behaviour, with an average period of 8.3 years (range 3.5 - 13 years).   There is considerable geographic variation in patterns of cyclic behaviour across the country, with cycles becoming significantly longer on moors located further north. However, this relationship is extremely noisy and latitude explains only 5.3% of the variation in cycle length.
Contact: Dr Daniel Haydon, Department of Zoology, University of Guelph, Guelph, Ontario, N1G 2W1, Canada

A molecular phylogeny of ichthyophiidae caecilians (Amphibia: Gymnophiona: Ichthyophiidae): out of India or out of South East Asia? by Dr DJ Gower, Dr A Kupfer, Dr OV oommen, Professor Dr W Himstedt, Professor Ronald A Nussbaum, Dr Simon P Loader, Dr B Presswell, Dr H Muller, Dr SB Krishna, Dr R Boistel and Dr M Wilkinson
There have been few evolutionary studies of the poorly known, limbless caecilian amphibians. As well as living in India and Sri Lanka, ichthyophiids are the only family of caecilians that extend into South East Asia. Using DNA sequences, we estimated evolutionary relationships among various ichthyophiids. The results indicate that India has the oldest lineages, while South East Asian lineages evolved more recently. This is consistent with the hypothesis that caecilians are primarily from the ancient southern continent of Gondwanaland, and that ichthyophiids dispersed into South East Asia from the Indian plate following collision with the rest of Asia about 60 million years ago.
Contact: Dr David Gower, Department of Zoology, The Natural History Museum, LONDON, SW7 5BD

Identifying the transition between single and multiple mating in fungus-growing ants by Dr P Villesen, Dr T Murakami, Dr TR Schultz and Professor Jacobus J Boomsma
The attine ants feed on fungus that they farm in underground gardens. We show that small, "primitive" agricultural ant species have queens that mate with one male, while the advanced leafcutter ants have queens that mate with multiple males. By mapping genetic data on colony kin-structure onto the phylogenetic tree of the ants we infer that there has been a single abrupt mating-system transition in the common ancestor of the leafcutter ants, coinciding with other social innovations like the extensive use of fresh leaves for feeding fungus gardens, massive increase in colony size, and the evolution of several worker castes.
Contact: Dr Palle Villesen, Department of Ecology & Genetics, University of Aarhus, Ny Munkegade, 8000 Aarhus C, DENMARK

Proceedings A (Mathematical, Physical & Engineering Sciences) http://www.catchword.com/rsl/13645021/previews/contp1-1.htm

Sea waves and mass transport on a sloping beach by Professor P Blondeaux, Dr M Brocchini and Dr G Vittori
Waves approaching the coast drive currents which shape the littoral area. In particular, vertical circulation is driven in which water masses flow to the shore near the surface and return offshore underneath the wave troughs. This return flow is particularly intense near the shore but its action is also important seaward of the breakers line because, due to its persistence, is responsible for much of the sediment transport in this area. We investigated the water circulation in the latter region and unravelled, for the first time, both the generation mechanism and the structure of this `weak undertow` flowing over a sloping seabed.
Contact: Dr Maurizio Brocchini, Instituto di Idraulica, Universita degli Studi di Genova, via Montallegro 1, GENOVA, 16145, ITALY

Thermodynamically consistent modelling of abrasive granular materials. Part I: Non-equilibrium theory by Dr NP Kirchner
We model the behaviour of rough geomaterials such as e.g. sands or soils. The former is influenced by a process called `abrasion`, by which we mean the peeling off of small roughness particles from the grain surfaces. How the process of abrasion should be accounted for in the mathematical model is however not unanimously agreed upon. Hence, three different postulates for the modelling of abrasion are proposed, leading in turn to three different constitutive models for rough geomaterials. These models are analyzed by means of continuum-thermodynamical methods, and their results are discussed and compared.
Contact: Dr Nina Kirchner, Institute of Mechanics III, Darmstadt University of Technology, Hochschulstrasse 1, DARMSTADT, 64283, GERMANY

Some general periodic solutions for optical cascading by Dr AV Porubov and Professor DF Parker
It is known to be possible, in suitably fabricated planar optical waveguides, that beams of light at a fundamental frequency and at its second harmonic can constructively interact. The process is known as optical cascading. The mathematical description predicts self-guiding of light beams, for which a number of mathematical solutions known as optical solitons have previously been identified. This paper identifies and catalogues a large number of mathematical solutions having periodic structure. It demonstrates the power of a search technique using the elliptic function of Weierstrass, which has previously been shown to be effective in other branches of nonlinear science.
Contact: Professor DF Parker, Mathematics and Statistics, University of Edinburgh, Kings Buildings, Mayfield Road, EDINBURGH, EH9 3JZ

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