Arabidopsis ROP‐interactive CRIB motif‐containing protein 1 (RIC1) positively regulates auxin signalling and negatively regulates abscisic acid (ABA) signalling during root development

Auxin and abscisic acid (ABA) modulate numerous aspects of plant development together, mostly in opposite directions, suggesting that extensive crosstalk occurs between the signalling pathways of the two hormones. However, little is known about the nature of this crosstalk. We demonstrate that ROP‐interactive CRIB motif‐containing protein 1 (RIC1) is involved in the interaction between auxin‐ and ABA‐regulated root growth and lateral root formation. RIC1 expression is highly induced by both hormones, and expressed in the roots of young seedlings. Whereas auxin‐responsive gene induction and the effect of auxin on root growth and lateral root formation were suppressed in the ric1 knockout, ABA‐responsive gene induction and the effect of ABA on seed germination, root growth and lateral root formation were potentiated. Thus, RIC1 positively regulates auxin responses, but negatively regulates ABA responses. Together, our results suggest that RIC1 is a component of the intricate signalling network that underlies auxin and ABA crosstalk.     

VOCAL BEHAVIOUR AND CALL DEVELOPMENT IN THE BULLFINCH (PYRRHULA PYRRHULA)

ABSTRACT

A sonagraphic analysis of the vocalizations of bullfinches Pyrrhula pyrrhula is presented and their behavioural contexts and functions noted. The vocal repertoire of the bullfinch is compared to that of other finches with particular attention to repertoire size and sexual specificity; the repertoire of 14–17 vocal categories is comparatively greater than that of most carduelines and the majority of vocalizations were given by both sexes. The development of nestling, fledgling and some adult calls is described. Early vocal ontogeny in the bullfinch was similar to that previously described for the chaffinch. The earliest recorded calls of nestling bullfinches showed a single fundamental. The independent use of two sound sources became apparent on the second day after hatching and the major elements of the three best studied call types were all derived from the lower fundamental of the nestling begging call.     

Genetic control of predator avoidance behaviour in Daphnia

1. The vertical migration behaviour in electrophoretically distinguishable clones of Daphnia magna Straus was investigated. 2. Clones differed significantly in their tendency to stay near the surface of the tank during the light phase of the daily light/dark cycle, indicating that vertical migration has a genetic component. 3. There was a significant difference in behaviour between juvenile and adult Daphnia: overall the juveniles stayed closer to the water surface than the adults, but the characteristic pattern of clonal differences persisted in the juveniles. 4. When an adult population of each clone was exposed to a fish predator in an experimental tank, the position a clone maintained in the tank at the start of the day had a direct effect on its survival. Clones remaining near to the surface of the water suffered greatest predarion.     

A Description of a New "Amoebozoan" Isolated from the American Lobster, Homarus americanus

ABSTRACT. Our knowledge of the diversity of amoeboid protists is rapidly expanding as new and old habitats are more fully explored. In 2003, while investigating the cause of an amoeboid disease afflicting lobsters on the East Coast, samples were examined for the presence of amoebae from the carapace washings of the American lobster, Homarus americanus . During this survey a unique community of gymnamoebae was discovered. Among the new taxa discovered was a small Thecamoeba -like organism with a single posteriorly directed pseudopodium. Although resembling Parvamoeba rugata , this amoeba displayed distinctive morphology from that isolate or any other amoebozoan. Phylogenetic analysis shows this amoeba is distantly related to the Thecamoebidae. In this paper we describe the unique morphology of a second species of Parvamoeba and discuss its phylogenetic position with respect to the "Amoebozoa."     

Redescription of Favella ehrenbergii (Claparède and Lachmann, 1858) Jörgensen, 1924 (Ciliophora: Choreotrichia), with Phylogenetic Analyses Based on Small Subunit rRNA Gene Sequences

ABSTRACT. The identification of Favella ehrenbergii, a marine planktonic ciliate, has largely been based on its lorica features. This approach is potentially problematic given the polymorphic lorica during this organism's life cycle. We isolated a population of F. ehrenbergii from the coastal waters of Incheon, Korea, and revealed its infraciliature using the protargol staining method. Phylogenetic analysis based on small subunit rRNA gene sequences was also performed. Results showed that this population possessed 16 collar membranelles (CM) and about 100 somatic kineties. These features are highly conserved, even in later dividers. As such, the number of CM and somatic kineties can be used as key characteristics for identification of Favella species.     

Burkholderia species are ancient symbionts of legumes

Burkholderia has only recently been recognized as a potential nitrogen-fixing symbiont of legumes, but we find that the origins of symbiosis in Burkholderia are much deeper than previously suspected. We sampled 143 symbionts from 47 native species of Mimosa across 1800 km in central Brazil and found that 98% were Burkholderia . Gene sequences defined seven distinct and divergent species complexes within the genus Burkholderia . The symbiosis-related genes formed deep Burkholderia -specific clades, each specific to a species complex, implying that these genes diverged over a long period within Burkholderia without substantial horizontal gene transfer between species complexes.     

The Boar-Operated-System: a Novel Method to Deliver Baits to Wild Pigs

ABSTRACT Bait-delivered pharmaceuticals, increasingly used to manage populations of wild boar (Sus scrofa) and feral pigs, may be ingested by nontarget species. Species-specificity could be achieved through a delivery system. We designed the BOS^TM (Boar-Operated-System) as a device to deliver baits to wild pigs. The BOS^TM consists of a metal pole onto which a round perforated base is attached. A metal cone with a wide rim slides up and down the pole and fully encloses the base onto which the baits are placed. We conducted a pilot, captive trial and found that captive wild boar fed from the BOS^TM either directly, by lifting the cone, or indirectly, by feeding once another animal had lifted the cone. Thus, we tested whether free-living wild boar fed from the BOS^TM and whether the BOS^TM could prevent bait uptake by nontarget species. We observed that free-living wild boar fed regularly from the BOS^TM and that the device successfully prevented bait uptake by nontarget species. The BOS^TM should be trialed more extensively to confirm its effectiveness and species-specificity to distribute pharmaceuticals to wild suids. If successful, the BOS^TM could be used to deliver vaccines in disease control programs as well as contraceptives to manage overabundant populations of wild suids.