Chromosomal variation in the house mouse

Although the standard karyotype of the western house mouse, Mus musculus domesticus , consists entirely of acrocentric chromosomes, there are 97 distinct 'populations' that are characterized by various combinations of metacentric chromosomes that have arisen by Robertsonian (Rb) fusions and whole-arm reciprocal translocations (WARTs). In this review we discuss the processes behind the origin and fixation of these rearrangements and then present a unified list of all known metacentric populations and evaluate their phylogenetic relationships. Eleven independent phylogeographical 'systems', each consisting of 2–25 metacentric populations, were identified in Scotland, Denmark, Northern Europe–Northern Switzerland, Southern Switzerland, Northern Italy, Croatia, Spain, Central–Southern Italy, Peloponnesus, Mainland Greece and Madeira. There are six isolated metacentric populations that do not belong to any of these systems. To generate phylogenies of the metacentric populations within each system, we determined those outcomes with the fewest steps regarding accumulation of metacentrics by Rb fusions, WARTs and zonal raciation and taking into account geographical proximity. These phylogenies should be viewed as working hypotheses that will be refined with further chromosomal and molecular data and improvements in methods of phylogenetic reconstruction. The list of metacentric populations and our phylogenies are also published electronically and can be accessed at http://www.studenec.ivb.cz/Projects/RobertsonianMice/ .  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 535–563.     

Dispersal in house mice

This review evaluates direct (live-trapping) and indirect (genetic) methods to study dispersal in wild house mice ( Mus musculus ) and summarizes field and experimental data to examine the causes and consequences of dispersal. Commensal house mice (associated with human habitations, farms, food stores and other anthropogenic habitats) typically show lower rates of dispersal than feral house mice (living in crops, natural and semi-natural habitats). However, early claims of long-term fine-scale genetic structure in commensal house mice (due to low rates of dispersal) are not supported by recent data. Dispersal becomes obligatory when habitat conditions deteriorate, but most dispersal occurs below the local environmental carrying capacity and is due to social interactions with conspecifics. Excursions are relatively frequent and probably allow mice to assess the quality of habitats before dispersing. Young males have the greatest tendency to disperse, apparently prompted mainly by aggressive interactions with dominant males. If they do disperse, females integrate into new groups more easily than do males. Dispersing house mice risk loss of condition or death, but may gain reproductive opportunities on arrival in a new location. House mice can be transported passively as stowaways with humans; this contributes to population persistence and genetic structure at regional scales and has allowed house mice to spread world-wide.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 565–583.     

Isozyme variation among and within North Atlantic species of Papaver sect. Meconella (Papaveraceae) and taxonomic implications

The high-ploid species Papaver dahlianum , P. lapponicum , P. laestadianum and P. radicatum were compared by means of enzyme electrophoresis. The diploid P. alpinum from the Alps and garden material of the assumed diploid P. croceum from Asia were also included. The results are compared with those of previous morphological and cytological investigations. Generally, only small differences were found among the species. The maintenance of 13 subspecies of P. radicatum as published from the Nordic area was not supported. The octoploid P. laestadianum was nearly identical to the decaploid P. radicatum and inclusion in P. radicatum is justified. The octoploid P. lapponicum was also very similar to P. radicatum and inclusion of it in the latter should be considered. The most distinct of the taxa was the decaploid P. dahlianum , and the maintenance of two subspecies, ssp. polare and ssp. dahlianum can be defended. A hybrid origin of P. radicatum (10x) from P. lapponicum (8x) and P. alpinum (2x), and of P. dahlianum (10x) from P. lapponicum and P. croceum (2x) has been proposed, but a more likely explanation might be that P. dahlianum , P. radicatum and P. lapponicum have all arisen by polyploidization from closely related diploids without hybridization.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 255−269.     

Evolution of the Malagasy endemic genus Nanos Westwood, 1842 (Coleoptera,Scarabaeidae, Epilissini)

The traditionally defined ‘Nanos group’, composed of the genera Nanos Westwood, 1842, Cambefortantus Paulian, 1986 and Apotolamprus Olsoufieff, 1947, represents the most recent Malagasy dung beetle radiation. Species in this group have been ecologically very successful with many being numerically dominant in local dung beetle communities in Madagascar. In this study the phylogenetic relationships of species in this group are inferred using molecular data from mitochondrial (cytochrome c oxidase I) and nuclear (rudimentary, topoisomerase I and 28S) genes.The monophyly of Apotolamprus is supported both by molecular and morphological characters, but that of Nanos, supported by only one morphological character, is questioned. Congruent species groups can be defined within Nanos on the base of morphology and molecular results. In addition to the phylogenetic study, the revision of the genus Nanos Westwood, 1842, s.l., is presented. Nanos antsihanakensis (Lebis, 1953) stat.n . is re‐established. Thirteen new species – Nanos pseudofusconitens sp.n ., Nanos magnus sp.n ., Nanos marojejyensis sp.n ., Nanos bemarahaensis sp.n ., Nanos andreiae sp.n ., Nanos mirjae sp.n ., Nanos pseudorubromaculatus sp.n ., Nanos pseudominutus sp.n ., Nanos mixtus sp.n ., Nanos ranomafanaensis sp.n ., Nanos manongorivoensis sp.n ., N. pseudoviettei sp.n . and N. constricticollis sp.n . – are described and compared with their most closely related taxa. Sphaerocanthon fallaciosus Lebis, 1953, is synonymised with Nanos fusconitens (Fairmaire, 1899) syn.n . and Nanos neoelectrinus Montreuil & Viljanen, 2007, with Nanos humeralis Paulian, 1975 syn.n . Lectotypes are designated for Epilissus fusconitens var. agaboides Boucomont, 1937, Epilissus punctatus Boucomont, 1937, Epilissus sinuatipes Boucomont, 1937, Epilissus semiscribrosus Fairmaire, 1898, Epilissus fusconitens Fairmaire, 1899, and Sphaerocanthon vadoni Lebis, 1953. Aedeagus and male pro‐ and metatibiae are illustrated for each species. This published work has been registered in Zoobank, http://zoobank.org/urn:lsid:zoobank.org:pub:C1F29A37‐E380‐4D87‐871F‐039227547156 .     

Effects of different methods of non‐lethal tissue sampling on butterflies

1. We investigated the effects of two methods of non‐lethal tissue sampling on post‐release flight behaviour (short‐term response) and survival (long‐term response) of two butterflies, Pieris rapae and Coenonympha tullia, within the same natural habitat. We applied three treatments: control (no tissue removal), wing clipping, and leg removal. Our study is the first to directly compare the effects of these common sampling methods. 2. We monitored the flight behaviour of the butterflies by following individuals immediately after their release. In 99 behaviour trials of P. rapae and 101 of C. tullia we found no significant differences in proportion of time spent flying or displacement per unit time among treatment groups in either species. 3. We used standard mark–recapture techniques continuously throughout the flight season to compare the survival of individuals. We marked a total of 687 P. rapae and 490 C. tullia butterflies. We found no significant differences in survival among treatments in either species. 4. We detected differences between the sexes in survival in P. rapae and flight behaviour in C. tullia. In addition to indicating differences in ecology between the sexes, these results also suggest that our analyses were sufficiently powerful to detect a significant effect of tissue removal had such an effect existed. 5. Our work is an important addition to the accumulating evidence that these methods of non‐lethal tissue sampling are generally not detrimental. These sampling techniques closely mimic conditions in the wild, as wing wear and leg losses occur naturally.     

Nuclear and mitochondrial DNA reveals isolation of imperilled grey nurse shark populations (Carcharias taurus)

Loss of sharks and other upper-trophic marine predators has sparked worldwide concern for the stability of ocean ecosystems. The grey nurse (ragged-tooth or sand tiger) shark ( Carcharias taurus ) is Vulnerable on a global scale, Critically Endangered in Australia and presumed extinct in parts of its historical range. We used 193 muscle and fin samples collected from six extant populations to assess global mtDNA and microsatellite diversity and the degree of global population genetic structure. Control region mtDNA diversity was low in every population, and two populations (eastern Australia and Japan) contained only a single mtDNA haplotype. Genetic signatures of recent losses of genetic variation were not yet apparent at microsatellite loci, indicating that this low mtDNA variation is not a result of anthropogenic population declines. Population differentiation was substantial between each population pair except Brazil and South Africa, F _ST values ranged from 0.050 to 0.699 and 0.100 to 1.00 for microsatellite and mitochondrial data respectively. Bayesian analysis clearly partitioned individuals into five of the populations from which they were sampled. Our data imply a low frequency of immigrant exchange among each of these regions and we suggest that each be recognized as a distinct evolutionary significant unit. In contrast to pelagic species such as whale shark and white shark that may cross ocean basins and where cooperative international efforts are necessary for conservation, grey nurse shark, like many coastal species, need to be managed regionally.